if I replace chainset and chain should I replace back cassette as well? I am replacing my chainset and chain, as its totaly worn and causing the chain to jump off when I pedal. The cassette is fairly worn too, but is not causing any problems. If I buy a new chain and chainset will these wear out a lot quicker if I leave the old cassette on?

You'll probably need to replace the cassette as well.

Generally once the chain has worn ("stretched") a little, it starts to wear down all the gears (front and back) that it touches. If there's enough wear that the front chainrings need to be replaced, it's almost certain that the gears on the cassette that you use most are also worn enough to need replacing. Usually the gears on the cassette will wear faster than the chainrings simply because they're smaller (so each individual tooth gets more wear).

The new chain will wear faster if the cassette is worn out, but a chain is generally cheaper to replace than a cassette. It should only wear the chainrings if you let the chain wear go.

You can look for signs of wear on the cassette, it will mostly be in the form of the teeth being thinner, often with a sort of "shark fin" appearance (sloped on one side). It's likely some gears (your favorites) will be worn more than others, which can give you something to compare against. If you can see signs of wear you should replace the rear cassette.

If you replace the chain and chainrings but not the cassette, I suggest paying very careful attention to how the chain runs when you first put it on.  If there's any kind of roughness to how the bike pedals, any kind of noise coming from the rear end when you pedal, or problems with shifting the rear, then it's probably time to replace the cassette.

Another thing you can do if you keep the old cassette is check the chain for wear regularly. If the chain wears down ("stretches") faster than it seems like it should, replace the cassette.


What is this simulator like device called? The following link: http://www.youtube.com/watch?v=I13wJyUZL_4 has a man limp to a bike (a Pinarello) leaning against a wall, climb on to it and ride the bike for a good minute to a minute and a half, while remaining stationary. My question is:

What is the simulator like device called? It looks like a bike treadmill, but what is it called?
How does the bike remain stationary on that device for all speeds? I would imagine that the bike would be stationary for only higher speeds, but that does not seem to be the case.
What are these devices used for?

Any insight on the above is most welcome.

Rollers. You have three drums, two at the back, one at the front and the front roller is powered by one of the back rollers. You can also get add ons to give you a breeze:

Balance is what is needed to stay on the rollers, also a wall (as per featured video) comes in handy.

Rollers are used for training purposes although they can also be used for demonstrations at trade shows etc. When riding rollers instead of an exercise bike you do need to balance as well as push the pedals, you can therefore improve your riding, not just your strength/endurance.


How do airlines calculate the cost of a Brompton? How do airlines calculate what to charge for a Brompton in a bag as checked luggage?

I’m flying on Iberia and from their website it looks like they will charge me US$75 to take it from BOS to BCN, but the text is not completely clear.

I wrote to them asking, providing weight and measurement, but they did not respond.

Do they charge based on the weight and size of the bag — as with other types of luggage? Or is the fee based on my declaring it to be a “bicycle” regardless of whether it might be small and light enough to be regular luggage?

Notes:

I will have it in a Radical Design Chubby, which is slightly bigger than the B-bag.

NOTE: This is about costs, NOT about protecting the bike.

This is a hard question to answer. Not only does each airline  have its own rules as to handle bicycles or what they consider oversized luggage — the airline counter staff at check-in have “discretion” which usually boils down to a degree of capriciousness. The checkin counter staff may or may not follow their own airline’s posted guidelines in terms of overweight, size, contents, or how much they charge. Usually this discretion is in your favor (ie they will waive the charge or lower it) but not always, especially if you come in with an attitude. In other words, there’s no consistency in what you’ll be charged unless you are obviously under weight, under size, and have non-surchargable contents.

That all being said, it’s still helpful to know the rules ahead of checking in so you know how much they charge for overweight and oversized luggage, versus how much they charge for a bicycle.

A bare brompton in a light bag (like the b-bag) will usually be underweight and just under the nominal size. Many hard cases will push it to oversize and some will push it overweight.

However, if you know the bicycle charge versus the overweight or oversize charge, you can go in with the following algorithm:

Approach counter and attempt to check in bicycle without any specific declaration. If the checkin clerk allows it without comment or extra charge, success!
If clerk attempts to assess oversize fee and it’s in excess of the bicycle fee, then state it’s a bicycle and get the lower bicycle fee.
If clerk asks what’s inside, ask first how much the oversize / weight fee is. If it is less than the bicycle fee, then declare the bike as “circus equipment” or “spare parts for a mobility device” (many places calling it “sports equipment” carries a special fee too) and pay the lower fee.

Note that I’ve found the brompton in a bag is very close to the 64 linear inches and with case can be close to the overweight limit. In those cases, it’s helpful to remove the saddle and pedals and put them in your other luggage. This will reduce both the weight and the overall dimensions as well as making it harder to break. You also want to remove all of the hinge locking bolts as those tend to snap.


Standard to compact swap I am looking to swap from a Shimano 105 standard 53-39 crankset to a 50-34 compact crankset.
My question is: will I need to adjust the height of the derailleur when changing to the new crankset?
And what else do I need to be aware of while buying the new crankset for this swap? Will any shimano crankset fits with my shimano drivetrain? etc.
Also my old crankset is a 10 speed and the new one i’m looking to get is 11. But as far as i’m concerned it should works just fine, maybe a bit less smooth when shifting.
Thank you

The front derailleur height always needs to be adjusted when making this switch. You should assume the front derailleur will need to be completely re-adjusted.
Dropping in a crank for a higher speed generation than the chain you're running usually results in some degree of rub between the chain and the large ring when in some of the small/small combinations. In some cases you might get chainsuck-type issues with the chain riding up on the ramps in these combinations too. The problem can typically be solved with chainring spacers. I do a set of Wheels Mfg 0.6mm spacers preemptively and it usually works.
Hypothetically, going from a 14t gap to 16t you could exceed your rear derailleur total capacity. In practice, the max cog and total capacity numbers of road RDs for some time now have been set up to avoid this possibility.


Replacing multiple spokes (9/36): more like replacing spokes or rebuilding a wheel? I've never built a wheel and while I'd like to learn one day I'm not going to learn on this one.

On Saturday my rear wheel ate my derailleur (and bent the steel hanger in the process)*.  No spokes broke at the time. After straightening the hanger I fitted the RD of my MTB (both are Shimano 9 speed) and it worked quite well.  After about 130 km I heard a ping, and shortly afterwards the broken spoke snagged the chain and I came to a sudden stop.  20 km gently home and I go to change the spoke (it's a tourer, came with 3 spares). When I get the cassette off I find another has gone, and all 9 of those that come outwards on the drive side are damaged.

So clearly 9 spokes need replacing.  Is it reasonable to buy 9 new spokes and lace them in and tension them one by one then true the wheel?  Or is that a stupid idea? I've got time to spend on the former approach as getting the wheel to a shop is a considerable hassle.

* there are some pictures on Strava for anyone who's interested in that bit.

If a wheel starts breaking spokes, the general advice is to have the wheel rebuilt with all new spokes, because all the spokes are likely weakened by fatigue and will keep breaking.

In your case, spokes broke because they were damaged. The other spokes are presumably not weakened, so you can just replace the damaged ones.

Of course, if the wheel has a lot of miles on it you may elect to rebuild.


Is it better to get an entry-level carbon bike or a similarly priced aluminum bike? I am going to buy my first proper road bike, and I have been comparing entry-level carbon frames with top-level aluminum frames in the same series (Giant Defy). What are the benefits of carbon vs. aluminum frames? Is it better to get an aluminum bike with higher-end components or a similarly priced carbon bike with lower-end components?

Essentially this is about low end carbon versus high end alloy. Carbon is typically lighter and less harsh (more vibration absorption) than alloy, but is not as robust. I doubt that the alloy is much heavier. I think it will come down to the difference in component quality and your budget.

Personally for a training bike I would probably go for the alloy, but that is driven by my financial situation. If the bikes are of similar price and the components are of the same quality, I would consider the carbon.  However I would not trade component quality for a carbon frame.

Edit : Seven years after the answer was give.
Many of the tecniques learn laying up carboon, and with advances in hydroforming alloy, have lead to allow alloy frames that are significantly cheaper to fabricate yet nearly as light (if not lighter) than low ebd carbon frames, while having teh characteristics of stiffness and complance where wanted. You can no longer discuss 'Carbon' and 'Non-Carbon' frames as most major manufacturers have 2, 3 or more variations of carbon from 'cheap and cheerful' to 'insanely light and expensive'. The cost saving in Alloy frames put into better compenets leads to a better bike for the same build cost. As carbon is consdidered more desireable by many, it fetches a higher price for the bike.

TD;DNR when buying a bike, look at the whole bike, not just the frame.


Cycling computers fits on any wheel size? I'm a newbie and I plan to buy cycling computer for my bike with 29" x 2.1 wheel.

Is it all cycling computers can fit on any wheel size?

I'm planning to buy Cateye Micro Wireless MC100w or Cateye Velo 7 online. Does them fit my 29" x 2.1 wheel?

Every bike computer you'll ever use has some initial setup where you choose the units, set the time and enter either a wheel size or circumference.

Cateye's take a circumference and there's a handy chart in both manuals to help you choose one, or you can measure it.

Micro Wireless
Velo 7


Amateur Bicycle Racing outside of the US I'm interested in taking a trip to Europe (although perhaps this question can apply to other areas of the world) and do some bike racing at a really amateur level like the equivalent of Cat 4 or Cat 3 in the US.  Mainly interested in road races.

Any ideas on where I can find information on these types of races if they exist?  Also any tips on administrative details of racing as a foreigner are appreciated.

If you are coming to the Uk then the British Cycling website is probably the place to start.


Squealing of rim brakes on a bike My bike for 2 days started to squeal whenever I use my back brakes it has been really annoying and I am trying to fix it. Please give me any suggestion that can help this problem

There are a few things one can do to help stop the noisy rim brake.  The noise is caused by the resonance created when the pads contact the rim and a very fast oscillation of the pads' grip force on the rim occurs. A contaminated pad or braking surface of the rim can contribute to this effect.  Even the presence of water can cause an otherwise quiet, dry rim brake to squeel when wet.   So first and easiest things to try are a good cleaning of the rim's braking surface. Use some Isopropyl alcohol on a rag and use to wipe down the braking surface of the rim. Use plenty of alcohol and change to a clean area of the rag often while rotating the wheel. Make several passes on each side of the rim.  This will remove dirt and oils from the rim. You can do the same with the pads' braking surface.  After cleaning the pads, take either sandpaper or a bastard file and use it to rough up the braking surface of the pad.  The pads rubber compound can harden over time and get a dirty glaze. Using the sandpaper removes the old or contaminated rubber and exposes the cleaner, softer rubber underneath, creating a better braking surface.  A grippier pad on a clean rim changes the resonance frequency of the system which may stop the noise.
One of the best ways to stop the noise requires a little mechanical work on your part. Toeing in the brake pads so that during braking the front, leading edge of the brake pad contacts the rim first, followed closely by the trailing edge. This has the effect of preventing resonance from getting started.  To accomplish the toe-in, loosen the pad fixing bolts. On the back, trailing edge of each pad, loop a rubber band securely around the pad. This allows your hands to be free to manipulate the tool and squeeze the brake lever.  After the bands are in place, line the pads up appropriately to the braking surface of the rim and pull the lever. While continuing to hold the lever secure (you can use some string and tie the lever closed if you need both hands free) and while the pads with rubber bands are held fast against the rim, tighten the pads fixing bolt. Release the lever and remove the rubber bands. Your pads are now toed in since the rubber band held the rear of the pad away from the rim while the front was in direct contact as the brake pad was secured while held in this toe-in position. Using a business card or piece of cardboard paper between the trailing edge of the brake pad and rim  while the pads are loosened and the brakes applied, squeezing the cardboard between pad and rim. This creates the front toe-in which is held fast when the pad fixing bolt is secured back .
Brake pads are made from different rubber compounds which can be softer or harder, depending on manufacturer or use-type the pad is for.  Changing pads entirely to ones with a softer compound may alleviate brake noise.


How do I avoid a pinch puncture? Newly mended inner tube went down within 15 minutes of pumping up and without any riding or even sitting on bike. Handpump only so no idea of pressure. What did I do wrong/ how can I avoid it happening again?

Most likely:

You didn't repair the original puncture properly, and air was still leaking from that site.
Whatever caused the puncture in the first place is still in the tire, and re-punctured the tube.
There was more than one puncture, possibly a small one that you didn't notice when finding the major one.

Possibly you also nicked the tube with a tire lever when getting the tire off. I think this might be what you are alluding to in your title.

By the way a 'pinch' puncture or flat usually refers to a puncture caused by the wheel hitting a bump that deforms the tire so much the tube is pinched between tire and rim. Frequent pinch flats indicate tire pressure is too low for the surface being ridden on.


Bike mounted camera bag Are there any bike mounted bags for a camera, that could safely hold my Sony NEX-5? I'd be happy enough if the camera fitted in with the 16mm pancake lens (as most of the shots are landscapes anyway). However, I was only able to find bags for cell phones or very slim compact cameras.

The camera dimensions without lens are per spec 111x59x38 mm (WxHxD); my own measurements give cca 114x63x39 mm. With the lens mounted the depth is about 62mm and the height just slightly bigger.

Sony NEX-5 with 16mm pancake http://a.img-dpreview.com/reviews/SonyNex5Nex3/Images/NEX-5_with_16mm-001.jpg
full size photo

Here's a top photo to get the idea of the thickness: link.

I'd like a bag that I could mount on the handlebar, allowing a quick access without having to step off the bike for a quick shot.

Or are there some solutions I could modify to my needs (more or less easily)?

I'm open to your suggestions! Thanks.

Ortlieb used to make two camera-specific bags that you could probably keep inside their handlebar bag, the Aqua Zoom and the Aqua Zoom Plus. These are now discontinued but you can still find them for sale.

However, the Ortlieb Ultimate is a great handlebar bag that snaps on and off the handlebars, and also has a camera insert. I highly recommend the Ultimate, although the mounting is a little tricky to install.


Would a recumbent bike be allowed at an ultra endurance event? & Why is no one using one? When I look at ultra-endurance races, for example, https://www.transcontinental.cc/ I always think two things:

Wow! I want to do this
This is ideal for a recumbent bike!

So, I wonder: Would this be allowed? I kind of assume there is no rule forbidding it so: Why is not everyone doing this? Recumbents are a lot more comfortable for long distance and at least in the flat they are a lot faster, two.

Rules for the transcontinental:

Ride from start to finish via controls listed here
No third party support, resupply or lodgings
No drafting (other than with pairs partner)
All forward travel must be self powered
Travel by ferries only by approved routes
All riders must maintain evidence of their ride
Inactive for 2+ days without contact = scratch
No insurance, no helmet, no lights = scratch
Riders must know and obey local traffic laws
Ride in the spirit of self reliance & equal opportunity

The TCR is a race (strictly speaking a time trial).  In that specific case, Wikipedia states that recumbents and tandems are not allowed (no citation is given).  I suspect that races will either say that or have a separate category (as is the case for the race across America.  I can't find a definitive answer for the Race ACross Europe as the you appear to have to sign up to get the rule book, but I have found implications that they are allowed.

For the more generic events in your title (of which there are many more), the case is likely to be more permissive. The TransOz (certificate error) for example, is run under Audax Australia rules, which state "A  rider  may  ride  any  type  of  cycle  on  a  ride  provided  it  is  only  capable  of  being  propelled solely by human effort and complies with the road rules*." Many such events (1200km and above) are listed by the Randonneurs Mondiaux.

Wikipedia has a note of interest in the article on Ultra-distance cycling (the admittedly vague definition there includes much shorter rides than those in the question, right down to the sort of distances I ride). "There are no longer any true ultra-distance bike races (i.e., that are longer than 300 kilometres (190 mi)) that are affiliated with cycling's main governing body, the UCI" so we can't really blame the UCI directly for the lack of recumbents on such rides.  The oldest ultra-distance cycling event (Paris-Brest-Paris definitely allows them.  This isn't technically a race any more, but first place finisher is a prestigious position.

* From other context on the site, this seems to be referring to local law for road usage, rather than, e.g., the UCI rules for road bike races (which would forbid recumbents).


Front brake only on a fixed-gear bike Is it considered safe-enough to only have a front-brake on a fixie in a urban area that has many hills?  I've been considering buying one, but I want to get some opinions before I move forward.

Yes. The front brake provides basically all of the stopping power in a bicycle, and recent tests in Bicycle Quarterly show that, in emergency stops, the distraction of attempting to use the rear brake may even increase stopping distance. Maximum bicycle braking power is achieved just before the bicycle starts to pitch over, as the rear wheel lifts off the ground. Once that occurs, it's trivial to lock the rear wheel with a brake or by using your legs on a fixed gear.

The main disadvantage of having a front brake only in extremely hilly situations is not being able to dissipate some of the thermal load of braking between both rims, so you risk overheating the front.


Stuck front derailleur On a ride recently my front derailleur seems to have gotten jammed. The levers wouldn't index and the derailleur itself wouldn't budge. After continuing the ride for a bit, the problem went away on its own. What could have caused this? And how can it be fixed more quickly in the future?

It is a Shimano Deore derailleur, and it was stuck in the smallest chainring position. The bike is new with less than 50 miles on it.

Often while mountain biking a twig or rock will get stuck between the swing arms on your front derailleur. This effectively locks the derailleur in place until the rock/twig works itself out.

If it happens again, stop and examine the derailleur. Generally you can't see the obstruction while you're riding.


Trek bike needs identification I have a bike that I want to sell but I have forgotten and lost all the info I had about it. It's a Trek road bike with 105's and some mods, like the head tube. It looks to me like the it was powder coated, or is that original? Anything you can tell me would be helpful. Thanks.

The steel cast lugs on the frame were introduced to Trek bikes in 1985.
Trek road bikes fell into three categories - touring, sport, racing - with wheel base, frame angles, and components appropriate to the category.

The tight seat tube to rear wheel clearance indicates a short wheel base racing bike.
The last year for a steel frame with a short wheel base is 1989 on the Trek 400, and 660.

For a steel frame with cast lugs between 1985 and 1989 I have found two racing bikes that came with Shimano 105 components.
- 1987 560 This model year head badge matches your frame
- 1988 560 Trek changed the head badge this year

So, it's possible that your bike is a 1987 560 with a swapped out handlebar and stem. Or, it the frame could be one of the other short wheelbase Trek road bike frames in 1987 with the handlebar, stem, and 105 components added.

Look at the catalog for 1987 and compare the parts on your bike with the parts on the bike in the catalog. If you get a solid match then you have a 560.

Also, as Jeff and Andrew indicate in the comments to the original post your serial number may provide you with information about your frame via the Serial Number Decoding Project.

Information derived from vintage-trek.com


Chain length and cassette tooth count relationship A little context first: I'm going to be riding in the French Alps and plan to tackle some of the classic climbs (Alpe D'Huez, Galibier, etc) next month - I currently have a Campagnolo Athena 50/34 (compact) chainset paired to an Athena 11 speed 11-27 cassette on the rear. None of the drive-train components are anywhere near worn enough for that to be an issue. Additionally, the rear derailleur cage is able to deal with the full range of the 11-29 cassette so this is also not an issue.

What I am considering is swapping out the 11-27 cassette with an 11-29 to give myself a little extra in terms of 'safety gears' - better to be overgeared than undergeared in my opinion!

My question is this: will I have to replace the chain when replacing the cassette, for example due to chain length?

My reasoning is that since I will only ever use the 29 tooth on the cassette with the 34 tooth chainring, that chain length should not be an issue. As above, the chain is not in need of replacement due to wear, so that is not part of the consideration. Perhaps I'm missing something?

I agree with @ Nik that it should not be an issue. You can verify  it by shifting the chain to the big ring in the front and the large cog in the rear. With your hands fold the chain over  itself to simulate it being two links shorter. Observe the rear derailleur. You should see two bends in the chains as it passes around the jockey wheels. If the chain passes thru the jockey wheels in a straight line the chain will be too short.


Derailleur hanger reverse It looks that the derailleur hanger is reverse and I've tried to check for a new one to replace and it seems to be very rare.

Is there any workaround to change it with a regular hanger?

The derailleur hanger appears to be installed correctly.

Notice there is a small bolt forward of the axle, that obviously goes in a hole in the  dropout and stops the hanger falling off when the wheel is out. The hanger also aligns with the dropout slot to allow the wheel to be removed.

I think your confusion comes from the fact that hangers on more modern bikes tend to have the lug where the derailleur mounting hole is located behind the axle, but these bikes also have downward facing dropout slots rather than rearward facing ones.

Edit after comments clarifying question:

The only new derailleurs that are designed for a 5 speed bike are Tourney. You could actually use any 8 or 9 speed derailleur as the actuation ratios are the same, but I doubt that would work any better than a Tourney derailleur on the 5 speed freewheel.

If you want to fit a different derailleur what you want is a 'conversion' derailleur hanger for horizontal dropouts that is held in place by the axle nuts and provides a standard M10 threaded mounting hole.

Googling for 'derailleur hanger horizontal dropouts' should get you started. What you are looking for is something like this - note I'm not sure if that's exactly what you need and I'm not making a recommendation.


Community Wiki: Which public transport networks allow you to transport a bike? In the UK I have never seen a public bus system that allows you to take a (non-folding) bike on the bus. (There are long distance coaches that do allow bikes, however I am asking about local busses.)

I know that some other places have buses with bike racks.

Where are the buses that have bike racks?
How common is it for buses to have bike racks?

In summary:

On some UK buses you may be able to put a single bike in the wheelchair space, ask the driver nicely.

In the US there seems to be lots of buses with bike racks on the front or back.  Mostly these racks can take no more than two bikes.  I was not expecting the land of the car too have better provision then the UK!

No where can you depend on being able to put your bike on a bus (due to lack of space).

New England

Massachusetts

The MBTA in the Boston area has bike racks on a fairly substantial number of the busses (70%, according to the web page). The Red, Blue, and Orange line subways, and Commuter Rail allow bikes outside of peak hours.

The Pioneer Valley Transit Authority in Western Massachusetts (Amherst/Northampton area, with several colleges) has bike racks on their busses.

New Hampshire

Manchester Transit has bike racks on most busses. Some busses have bike racks which accommodate three bikes.

Concord Area Transit has bike racks on most busses.

Nashua Transit has bike racks on all busses.

Advance Transit in the Upper Valley region of Vermont and New Hampshire (Hanover, NH, White River Junction, VT, the Dartmouth College area) has bike racks on many of their busses.

Vermont

CCTA (Burlington area) has bike racks on all busses, as well as bike lockers.

GMTA (serves rural Vermont, and recently merged with CCTA) also has bike racks on all buses.

The Amtrak Vermonter rail line (connecting St. Albans, Essex Jct. (Burlington), Springfield Mass., New York City, and Washington DC) now offers carry-on bike service as of May 2016. (There is a limit of 3 bicycles per train, a $10-$30 fee depending on destination, and bicyclists are asked to arrive early at the station)

Maine

METRO Bus (Portland) has bike racks on all busses.

Even busses with bike racks can only carry two bikes at once, which means that if many people use them, you may need to wait a while before finding a bus with space, and some of them have restrictions (such as not on express busses, or not when the busses are replacing a train). In general, I find it's best not to rely on being able to take bikes on public transit, but use it as a backup option for when the weather turns bad, you have an injury, or something of the sort, and you still want to take your bike home.


Giant Toughroad SLR 1 for long distance tour I will be undertaking a cycle tour of around 2700km (~1800 Miles) in Europe this summer (Early July to the middle of August) and have been looking at the Giant Toughroad SLR1 as the bike to go for.

From the (limited) content I have read online, the bike seems to be a good fit but I wanted to get the opinions of some people who might have used this bike for undertaking something similar to the above.

I will be attaching rear panniers to it and possibly front as well, going for Ortlieb panniers.

I am 193cm tall and weight 90kg (6ft 3" and 200lbs).

I am quite new to bicycle touring so was wondering if anyone has been in my situation and what recommendations you have regarding this bike (or maybe others).

Also, if you buy a bike online direct from the manufacturer, do you need to do much assembly when it is delivered (from Giant in particular)?

You're looking at around 60km a day on average (presumably a bit more but some rest days).  The bike can take it with no trouble. I sometimes ride that sort of distance on a comparable (but older spec) bike, lightly loaded but it's heavier to start with.

The tyres may not be optimal if you're almost all on tarmac, though they're probably pretty good for dirt roads -- tyres are easy to change when you've planned your route. (I'd go for something like marathon plus 35 or 38, but that's partly habit).
You may want to swap out the grips for something offering more than one hand position (like these Ergon GP3s that I use)
You'll need to train for it on the bike you plan to use.  We've got quite a few questions about training here, so I won't go into details, but this is the only way to get the fit right and make sure the saddle is right for you.
You might want to upgrade the pedals, depending on how the stock ones work with your shoes.  This could be clipless, toe clips, or just normal platform pedals that your shoes don't slide around on.

Giant have lots of dealers in many countries so it's worth checking whether you can try one for size, even if it means making a special trip.  I'm about your size and bought online with no real problem (GT, not Giant, XL frame) but I consider myself lucky that it fits so well.  In theory assembling is easy; in practice my front derailleur wasn't set up square and took a lot of fiddling to get right -- perhaps you shoudl check out how much a shop or mobile bike mechanic would charge to put it together, assuming getting it through a dealer isn;t an option.


Shimano Steps ebike E010 and E012 errors: DIY fix possible? My Shimano Steps-powered e-bike is frequently but irregularly giving me the errors E010 and E012. In the E6000 Series Dealer’s manual and E8000 Series User's manual I found the following:

  E010:
  A system error was detected.
  Power assistance is not provided during riding.
  Press the power button of the battery to turn it on again.
  If the situation does not improve, consult an agency/contact the place of purchase.

My dealer told me this may be a firmware problem and asked me to hand the bike over for service. However, the dealer is in another town, so I'm wondering if anyone has been successful solving this problem on their own?

The E012 error means that the torque sensor is misaligned. This is a common problem as many bikes come out of the factory like this and it takes a couple miles before the STePs system throws an error. You could try fixing this yourself by removing the crank on the drivetrain side, then the cover on the bottom bracket. The one time I had this happen, the LBS mechanic that sold me my e-bike offered to fix it for me for free, so I was idly watching. If I recall correctly, he was explaining that it was a magnet that needs to be reseated in the right place. Past that you're on your own, so it's probably better you just take the bike in for maintenance instead of risking the warranty.

Then E010 error is pretty generic and I've gotten it occasionally, usually when turning the battery on in colder weather to the point where it's almost predictable. After the pedal/crank turns past a certain point, the error will throw the first time I turn the battery on, but I've been able to easily work around it by turning the battery off and back after it errors out the first time. Likely, it is a firmware issue, but Shimano hasn't fixed it (yet). Until they do, it's not too much of an inconvenience.


Will degreaser formula 88 harm your tire? I was using degreaser formula 88 and got some on my tire. I rinsed it off with some water and then the next day the tire had cracks and was faded. Will the tire get messed up ?

According to the FORMULA 88 Material Safety Data Sheet, this product is not dangerous, and is soluble in water. Washing it off was the best you could do.

My guess is that the solvent has dissolved some of the components of the tire rubber, leading to the fading and cracking you see. Only time will tell if the tire has been structurally compromised.

The most basic precaution would be to buy a new tire before this one fails.

You could continue to ride this one, if there are no signs of bulging from the internal pressure in the tube. But the conservative advice would be to replace it now.

Personally, I would put it on the back wheel and continue to ride on it, but keep it under observation. If the damaged area is smaller than a tube patch, I'd glue a patch on the inside. But if it starts to bulge, then I'd replace the tire promptly.


Tire and rim sizing, tubeless conversion? I am looking to shave some weight off my wheels. I am currently commuting on a 26" MTB.

The ETRTO size of the rim is 559x22 and the tires are 559x54. As my commute is through the city center, I want to change to slick tires.

The question here is will the 559x42 slick tires fit on the rim?

Also, can I go tubeless with "Stan's NOTUBES" conversion kit?

Can't speak to the tubeless conversion kit, but pretty much any 559xwhatever tire should fit those rims. A given rim width can accommodate a wide range of tire widths. Seeing as how your desired tires are only 2 mm different, you'll definitely be OK.


GPX to Profile like Giro d'Italia? my dream is to have a tool that generates profiles like Giro D'Italia:

in which:

we can add text of locations;
we can add the maximum profile signal

Does https://veloviewer.com/ do it for you?

Looks like it ties into strava.


Why is my bike looking so light yet so cheap as I make a list of what I need to build it? I've been searching around to get a rough price for a home-built carbon fibre bike. I'm almost sure I've left something out though as my bike looks like it will be weighing a mere 5.8kg for only €1230! The parts I've found so far are the following:

Bicicleta carbon frame
Miche Excite Road Wheelset
Shimano Ultegra 6800 11 Speed Groupset
ITM X One Carbon Road Handlebar

There's hardly only 4 parts I need so could someone point me towards what I'm missing.

Note: I have left out the saddle, brakes, pedals, cables, seat post, water bottle cages, stem, tire and tubes as I plan on buying that at my local bike shop

I'd be careful with a random carbon fiber frame from the internet, since you don't know how well its built (and frame failure can lead to serious injury). We've discussed this at length multiple times on this stack exchange, so you can search it. There are also a lot of fakes of major manufacturer bikes online, so you should be wary of those too, especially high end carbon fiber ones. It's very easy to make two bikes that look identical from carbon fiber, but one is much less safe than the other. Read this article for an example of the horrors (including for other fake bicycle products).

Personally, I'd rather buy a bike from a major manufacturer which I know was built correctly at the same price point even if its components aren't Ultegra and it isn't carbon fiber.

Also, its hard to know how well the bike will fit, versus just trying a bike out at the shop and getting a better idea of fit. This takes quite a bit of experience (and is pretty inexact too; you may hate something that fits on paper).

--

I'll assume the groupset follows what Chain Reaction Cycles is selling at the moment: Front and Rear rim brakes, front and rear derailleur, brifters, crankset, cassette, bottom bracket and a chain.

It's not clear from the product page that your wheelset has a 11 speed compatible freehub, so if it doesn't have a 11 speed compatible freehub, you need a different wheelset.

You're still missing tires, tubes, seatpost, saddle, headset, pedals, stem, cables + cable housing, drop bar tape.

You'll also need some tools to work on the bike (a torque wrench is critical on carbon fiber), some of which you may want to leave to a shop (e.g. a headset press).  And other ancillaries like appropriate greases and stuff for working with carbon fiber, of course.


Adding Brake Caliper Cable Tension SRAM Rival I have come across a really annoying issue that I just can't seem to put a finger on, and it is causing nothing but heart ache and frustration.

I was checking to see how much wear I had on my brake pads, unfortunately the lighting was too dark for me to see correctly while the pads were seated in the Caliper, so I had to remove the pads from the caliper. Once I was done checking the brake pads, I re-seated them and noticed that there was now a lot of play in the shifter/brake lever (I'm using a combo of SRAM Apex & Rival (Brakes) components).

My bike has an internal cable for the rear brake and I believe that the issue may lay here.

So I did what I thought would be a straight forward brake tensioning adjustment, but now there is so much play in the lever and I'm finding the one of the calipers isn't returning to it's usual position. I have tried everything, YouTube, adjusting the adjustment barrel thing, unfortunately the Rival Brakes don't have an adjustment screw on them.

I have tried everything I can think of and I just can't get it back to how I had it set before. Any advice on how I can overcome this problem will be greatly appreciated!

Thanking you in advance,

Stu : )

It sounds like there is an issue with the return spring rather than the cable tension.  If the brake is pulling easily and not returning, I'd guess it may have become disconnected during your removal process.  I would compare the setup of your return spring on your working brake with the one on the non working brake.  It maybe as simple as clipping the spring wire back under a tab of some sort.  It looks like on that model brake the return spring is a coil wire deal on the back of the brake.


Can a 12 speed Shimano micro spline cassette be used with SRAM Eagle 12 speed components? Is it possible to use a Shimano 12 speed micro spline cassette with a SRAM Eagle 12 speed chainring, derailleur, and possibly chain? Or are there any incompatibilities, such as a Shimano chain also needing to be used?

SRAM and Shimano 12 speed are cross compatible. The pull ratio is slightly off (offhand I believe it’s 1.76 for SRAM vs 1.7 for Shimano), but it seems to work fine in the real world.
To get the nice Shimano “Hyperglide+” shifting, you would need both a Shimano cassette and chain. It would shift without it, just not as well.
Of course, you cannot use SRAM XD cassettes on a Shimano MicroSpline freehub body or vice versa.


Replaced tyre and tube, now the rear gears will not stop Just put on a tyre and innertube, fits perfectly, but now when I stop pedalling the gears at the back keep moving so the chain just sags down so much that it hits the wheel etc.

Any ideas on how to fix it, or why this is happening?

Cheers guys

Jeremy

Sounds like you have not put the wheel back in properly and have somehow managed to over-tighten the freewheel/freehub, causing it not to spin freely.

You will have to take the wheel out and check that the axle nuts are done up properly and that the freewheel/freehub works. At a guess you are not using a quick-release lever, with nut-style axles you must tighten up each side gradually - 1/2 a turn each side once the wheel is in place or else you can tighten the axle (instead of putting the wheel in).

Do check for 'play' in the wheel once it is back in, if there is any then you will need to get it adjusted - wheel back out time... If you cannot work out what is going on with it, visit a friendly LBS during a quiet weekday to see if they can put it right for you whilst-you-wait.


What to do with old tires? I recently upgraded to puncture resistant tires on my road bike. The previous tires are old, but still usable. Is there any value to doing anything other than throwing them out? For instance, is there any reason to keep them? Is it possible to sell used tires? If no one wants them, can/should they be recycled?

I usually gift them to people who need them.

Edit: To expand more on my answer, I use rather expensive tyres and I want them in mint condition. So after a couple of months I'll most probably change them. The old tyres can still give 6-12 months of quality riding time to someone. So I'll post on local riding forums with closeup photos of the tread and usually people will get them.


10-speed chain too short, can I add links? I purchased a new KMC DX10SC 10-speed 114 link chain to replace my worn out chain. I'm running a mountain triple and it seems that The chain is slightly too short at it's full length. I can't get in the big ring on front chainring and rear cassette at the same time. I don't necessarily want to ride like that (terrible crosschaining), but I would prefer to have the capacity to do so since If I shift up to the top of the cassette it locks the derailleur in to place due to the tension and I can't shift out of it.

So, can I simply push out the pin and add a few more links and re-join it the same way? I'll have to buy another chain presumably to extend it or find some spare 10-speed links. Is this something that causes problems with 10-speed chains or can I do it the same way I've always done with my 6/7/8 speed chains?

I figure my alternative is to get a short patch of chain and use a couple KMC missing link quick links to join the sections together.

10 speed chains aren't designed to rejoined like 7 speed chains. The outer plates are thinner and the pins sit flush with the plates, which leaves little margin for error when reinserting the pin. The pins are often riveted too so they can't be correctly reinserted even if you are able to perfectly line it up. I'd use extra connector links instead of trying to reinsert the pin.


What size chain for 200gs FC-M202? This FC-M202 200gs has a label saying For NARROW chain only:

So what size exactly? Wikipedia lists three sizes:

3⁄32 in (2.4 mm),
1⁄8 in (3.2 mm),
5⁄32 in (4.0 mm), or
3⁄16 in (4.8 mm)

I can't find much information about the FC-M202 (is that because it is a very old crankset?), but this thread, Very Old Shimano 7 speed replacement mentions Shimano IG chain, and this question, KMC Z8S IG or HG compatibility, states that IG chains are not a good idea (as they are hard to find and can't be used with HG cassettes), and SRAM would be better.

FWIW, I currently have a FC-TY33, and the FC-M202 has the same gear ratios (48/38/28). I am not sure what chain I currently have (IG, HG or SRAM) - I have had a close look at it and there appears to be an italic 'I' stamped into each link, but my eyes could be fooling me (and TAIWAN stamped on the rear side of some of the links).

However, it certainly does not look like this (nor does it have Shimano written on it):

The chain would have been purchased circa 2005, maybe.

I have an FD-M735 and a RD-M735.

My rear sockets are 28/24/21/19/17/14/12/11 (I think, I may have miscounted slightly), so 8 gears, but only seven of which are accessible.

Narrow means whatever was derailleur chain at the time, as opposed to wider singlespeed chain. The actual chain type is determined by the cassette and is very probably 7-speed.

The inch designations listed on Wikipedia are not commonly used except to distinguish between 1/8" singlespeed chain and narrower derailleur chains that are all lumped under 3/32" and distinguished by number of speeds in cassette. Note that on Wikipedia 7.1mm and 7.3mm both become 9/32".


Bicycling and a Right Turn Only Lane? When commuting with a bike I usually stick to the right lane (I am based in the USA). When approaching a right turn only lane while biking, should I stay in the turn lane and signal to the car behind me that you I'm going forward rather than turning right, or should I move to the center or left lane?

The key thing, is that you never want to be to the right of cars that are turning right.

Depending on the exact lane setup and traffic amounts, I would do one of these:

Merge left into the go-straight (left) lane, so that anybody turning right is in a separate lane to the right of me.
Be in the center or left third of the right-turn lane, so that anybody turning right is blocked by me and has to wait for me to get into the intersection
Split the lane, riding in between the left and right lanes.

Exactly which I actually do depends on the traffic levels and what the far side of the intersection looks like. I would only do the 2nd or 3rd options if right-turning traffic is low and there's clearly space on the far side of the intersection for me to be to the right of the going-straight traffic (2 lanes, or 1 lane with a bike lane or wide shoulder).

To repeat: the main thing is to not be to the right of cars turning right. Get to their left or directly in front of them.


Should I attempt a long trip? I daily cycle 20~30 km in (high) traffic going between home, faculty and other places. However I have never been outside of city or in any kind of competition.

Now I have to go to another city and I was wondering if it is a good idea to attempt this journey with my bike.

The route:

180 km, Bucharest to Focșani, Romania.
total ascent 900m (mostly final part)
total descent 750m
national road (100 kph), well maintained, 1 or 2 lane(s) per direction, no median barrier
100% asphalt
passes villages and 2 major cities.

My bike I think it is a hybrid bike (or MTB maybe), but nothing high-end.

The weather is nice and at return, if that won't be the case, I have to option to take the train (it hopefully should allow for carying the bike).

My main concern is traffic (I am used to traffic, but in the city) and the bike breaking down.

I don't think there will be physical problems from me and I expect to make it in less than 12 hours, but again I never attempted anything like this so...

The prospect of this road trip with my bike really excites me, but I don't want to do something foolish. So should I go for it, or just take the damn bus? If the bike breaks down and I cannot fix it what are my options? Anything else I should be worry about?

180 km is a long way for someone who only normally does 20-30km (to quote @PeterH in chat).

To my way of thinking, you could do it, with some pre-conditions

Do some longer rides, where you ride 30km to somewhere, have lunch, and ride back.
Ride on some of the potential routes, to understand the traffic situation.
Plan ahead, so that you do it over two or more days.

I would check out where other people ride. For example

Strava activities near Bucharest
Strava activities near Focșani. A lot of these go into the mountains, but you may find some that go where you want.

And use Google Street View for reconnaissance.

A few related questions and answers

What is the necessary equipment on longer bike rides?
Help for a 169 mile bike ride
Training involved to ride 175 miles (281 km) in a day


Rear disc calliper won't fit, disc mount bent? I am upgrading my MTB to disc brakes.
I have disc compatible wheels and a set of Shimano M446 Postmount callipers and 160mm rotors.

Front fork is a Manitou who decided to jump on the Postmount wagon pretty early, so setting up the front was straightforward. Mount the disc to the wheel, calliper to the frame and align everything. Done.

The rear disc mount is 51mm IS, therefore I bought a Shimano rear IS to Postmount adapter.
I mounted the rear 160mm disc to the wheel and installed the wheel, making sure it sits nice and straight in the dropouts.

Trying to mount the rear calliper to the adapter, I noticed it doesn't fit. The adapter is a couple of mm too far to the left, so the calliper bolts will not fit. When looking from above, the disc and adapter are not parallel. The adapter itself is not damaged and is straight. The problem is with the IS disc mounts on the frame itself, they seem to be at a (slight) angle and not parallel with the disc. Using spacers to solve the problem is not an option, because of the angle between calliper and disc. As far as I know the bike has no crash damage and there are no signs of damage anywhere near the disc mounts. Probably something went wrong with manufacturing the frame?

In case of a steel frame I could carefully bend the disc mounts back to be parallel with the disc, however as this is aluminium I am a afraid of damaging the frame. What are my options? Can I attempt to fabricate asymmetric spacers that will cancel the angle difference?

There is a tool call a disc brake tab facing tool.

This tool is designed to correct the alignment of IS disc brake tabs with the dropouts of the frame, so that the rotor will be correctly aligned with the caliper.

See instructions below from Park Tool Repair Help Blog:

Disc Brake Mount Facing (IS type) with DT-1

This article will discuss the use the Park Tool DT-1 Disc Brake Mount Facing Tool. The DT-1 is a precision tool system designed to machine disc brake mounts flat, parallel, and in the same plane.   Use of the DT-1 helps ensure proper disc brake setup and performance.

The DT-1 includes everything needed to face the disc brake mounts on frames using 10mm axles and forks using 9mm axles.   It also includes special adapter bushings to allow facing of disc brake mounts on frames using 12mm through axles and forks using 20mm through axles.

Being a precision cutting tool, the DT-1 should be used and stored with extreme care.   Always liberally apply cutting fluid (we recommend Park Tool CF-2 Cutting Fluid) to the brake mount and cutting teeth of the facer during each use. Components should be kept clean and the facing cutter should be periodically wiped with an oily cloth or rust inhibitor before storage, especially in a damp or humid environment.   Store the DT-1 in its original packaging or other safe location.   Like all cutting tools, the facing cutter included with the DT-1 should be periodically replaced or sharpened by a qualified technician.

Installation of tool:

135mm Rear Frames: Insert the longer axle into the body of the DT-1. The axle pinch bolt should face to the back. The side of the axle with the C-clip goes to the dropout side. Install the axle fully into frame and secure axle. NOTE: Bikes with 130mm spacing will easily flex open to accept the 135mm axle for purposes of facing.

135mm frame with 10mm axle.

100mm Forks with 9mm Axles: Insert the shorter axle into the body of the DT-1. The axle pinch bolt should face to the back. The side of the axle with the C-clip goes to the dropout side. Install the axle fully into frame and secure axle.

100mm wide fork, with 9mm axle.

12mm Axle Rear frame: Insert axle through left side dropout, through 12mm ID spacer, and through DT-1 body. Smaller end of spacer fits into body of DT-1. Secure frame axle. Push body of DT-1 to the left until spacer contacts dropout. Secure axle pinch bolt.

12mm rear through axle with DT-1.

20mm Through Axle Forks: Insert axle through side dropout, through body of DT-1 and through 20mm ID spacer. Smaller end of spacer faces left side of fork (disc mount side). Push body of DT-1 to left until spacer contacts dropout. Secure axle pinch bolt.

20mm through axle with spacer.

Facing Procedure:

Assemble DT-1 into bike as described above.
Loosen knob setscrew. Slide knob to end of facing cutter shaft, next to 10mm hex.   Tighten knob setscrew.
Loosen pinch bolt and pivot bolt just enough to allow lower body and upper body to pivot and slide on axle.
Slide body against retaining ring or bushing.
Insert cutter through lower hole of body.   Insert piloted tip of cutter fully into hole of brake mount.
Tighten pinch bolt and pivot bolt to lock position.
Turn knob clockwise while applying hand pressure to face surface of brake mount.   Remove only enough material to create a clean, flat cut around the face of the mount.   NOTE:   For speed and leverage, a ratcheting wrench with a 10mm socket can be used to turn the 10mm hex head on the cutter .

With teeth of cutter contacting face of brake mount, loosen knob setscrew and slide knob on shaft of cutter until contact is made with body.   Tighten setscrew.

Pull knob and cutter from lower hole and insert through upper hole. Loosen pinch bolt and/or pivot bolt to fit piloted tip of cutter fully into hole of brake mount, then retighten.

Note position of cutter teeth. If cutter teeth contact brake mount and there is gap between knob and body, complete facing and stop. If knob contacts body before cutter teeth contact brake mount, OR, if knob contacts body at the same time cutter teeth contact brake mount, reset the tool as in step 3, and face the upper mount. Use this setting to then face the lower mount.

Turn knob clockwise while applying hand pressure to face surface of disc mount.   Continue facing mount until knob stops against body.    The facing process is complete.   The upper and lower mounts should have a clean, flat cut and the faces should be parallel and in the same plane.   Remove DT-1 from frame.

NOTES ON DT-1 USE:

Like all machining, use a cutting fluid such as Park Tool CF-2. If there is some "chatter" on the surface, the cut will still be square to the axle and the brake will mount properly to the disc. Change the amount of pressure and speed of the cutter to reduce chatter.

Use a cutting fluid such as CF-2.

When cutting the surface of the disc mount, it is important to achieve a flat surface for the brake mount. In the image below, both mounts are adequately faced. Notice the left and right mount do not look identical. However, if the two mounts were faced to the same reference on the cutter, the job is done.

Adequately machined caliper mounts.

It is important to note the "foot print" left by the cutter and compare this to the "foot print" or contact area of the caliper body or caliper body bracket adapter. Some mounts require significant machining, and the size of the machined surface may be smaller than the bracket.

The adapter bracket above will have a larger contact area then the machined surface. Use spacers in this case.

Close up of a machined cut likely to need spacing.

Spacers in place for the adapter bracket.

If the caliper mount is equal to or smaller than the machined area, no spacer is required.

This disc mount-to-caliper interface will not require a spacer.


Brake callipers not long enough to allow adjustment of pads I upgraded the standard Tektro brakes on my SE Lager to Shimano 105s. The braking performance is vastly improved. I also have Charge Plug wheels, rather than the stock wheels.

However I've noticed that there's not quite enough adjustment in the calipers to position the pads correctly. Even at the lowest position in the caliper arms, the pads are still very slightly too 'high' and overlap the upper curve of the rim.

Is this a problem? Is there anything I can do to solve it?

Those pads do look ever-so slightly too high on the rim, the main danger being that any slight vertical eccentricity could result in the pad contacting the tire and causing a blowout.

There are two main solutions:

Firstly, you could use a round file and simply file out the bottom of the slot slightly to increase the clearance.  This works best if you only need a very small amount of additional reach and are willing to accept permanently modifying your brakes.

Secondly, you could buy a set of brakes with a longer reach.  The Shimano 105mm calipers are 39-49mm reach; if you instead purchase some higher-quality dual pivot calipers that are 47-57mm reach you'd have plenty of room for adjustment and should be able to achieve equally good braking capability.


Bottom Bracket issues So I took the old bottom bracket out of my hybrid frame, FSA Platinum ISIS Bottom Bracket 68 x 118mm.

I then replaced with a Shimano BBUN55 Square Taper 68 x 11.8cm. Then realised that this was a square taper, not the star shaped of the previous FSA. Now obviously my crankset won't fit.

Happy to purchase another crankset, as mine has 6,000km+ of hard way & I really don't fancy taking it back out again.

Would something like:
http://www.chainreactioncycles.com/fsa-vero-compact-n10-11-chainset/rp-prod129455  fit?

Otherwise, should I take it out and order the correct one? The only BB I can see if the same one, and they only seem to last 3,000km :(

I'd consider going back to square taper a bit of a downgrade. And buying a crank to suit the bottom bracket is a little bit backwards in thinking. That crankset you linked to would be fine assuming you want to keep the BB. FSA has been pretty good in my experience, but I can't say that with certainty for your case because I've only dealt with their more expensive stuff.

The thing you'll have to watch out for is getting the right chainline. If you have the wrong length spindle, you'll end up shimming something, which I never recommend unless absolutely necessary, or just buying a new one anyways. Without more information I couldn't make an assessment of the right length spindle for your bike. I didn't have any luck on FSA's website in finding their suggested spindle length to produce the standard 43.5 mm chainline, or whatever is appropriate for your case.

I would go order the correct BB if I was you, as long as you're willing to keep your crank for a little while longer. A new crank AND BB might be in order if you can afford it and want a smooth new setup. I don't know what you're doing though if those FSA BBs are only lasting 3000 km, though. I've had that exact same one, and it lasted so long I sold the bike before it wore out.


Installing fat bike tires on a BSO for winter riding(condition of averaging -23 C for 2*17km). Is it doable, safe? As for my other question Winter riding: Is it safe to ride on a BSO/cheap bike at temperatures below -15°C on icy or damp roads? I've got a lot of suggestions of getting studded tires for winter roads. The road I take is not very well maintained and there's a lot of bumps and ice... and salt. BUT! I still haven't abandoned my plan of commuting in winter Montreal. Though I haven't seen anyone mentioning fat bike tires. The idea came when I went window shopping for studded tires prices and saw fat bike tires as a cheaper investment. Although I do not know whether it is feasible or not to install them on my BSO.  My BSO is 21" and I will need to ride 2*16 km everyday (commuting).

Fat bike tyres (3.8" or bigger) are unlikely to fit in the frame or fork of your BSO.  In addition, such large tyres require wider rims (typically 50-100mm internal width) which you are also unlikely to have.  Finally, fat tyres have their advantage in 'floating' over sand or snow, however they won't grip on ice as well as a studded tyre.


Feasibility of bike frame design by a layperson I'm sure for many bike builders, their ultimate dream bike starts with a frame that they designed themselves. And herein lies the problem: it seems that modern means of frame production (e.g., hydroforming) implies very sophisticated shapes of frames, not just a bunch of round tubes welded together.

Is the design of a frame (together with rigidity calculations) something a layperson can reasonably pick up without taking a Mechanical Engineering degree? I'm curious about how all this stuff is actually learned and whether there are some places (training?) that explain it less than a few years.

Interesting question and way of looking at it.

Here's my take: those in the bike world who would seem most qualified to design scientifically optimal frames, which involves both mastery of all the advanced fabrication techniques and materials that are now available and the motivation to empirically figure out the handling and ride feel elements that can be hard to quantify, and which suffer when you just make things more stiff ad infinitum, usually end up working for companies where all the actual design decisions get made from a marketing and immediate profit perspective. The main question they spend their careers answering is, "How do we stay in the black in the next 2-3 years?" That's not to say that proper engineers aren't responsible for making some good bikes or moving the needle of progress and knowledge in the bike world forward, but they are not the only ones who do, and the mainstream companies they work for wind up pushing back the wrong direction on the needle quite often as well.

Small framebuilders usually aren't proper engineers, they usually don't have access to the same range of advanced materials and techniques, and they work in environments where myth, lore, and intuition can have louder voices than scientific process, but they're usually in a better position to deliver optimized ride feel and handling experiences to the end user. A lot of the major trends and advancements in the industry get started by non-engineers working at a grassroots level. And, to answer your question, you can get started in that world by riding, reading, geeking out, taking framebuilding classes (usually 1-2 weeks), and participating in existing forums.

Some other important pieces:

Round tubes start to have some meaningful disadvantages for high level athletes in high level competition. For everyone else all the rest of the time, bikes based on round and simple ovalized tubes aren't stiffness- or weight-impaired in any meaningful way.

If one does want to mess with more physically dialed frames, you don't have to be an engineer. You can just start doing carbon layups in your garage. Yes, without training you probably won't be able to do it with the same level of sophistication an engineer could. But you also won't be hamstrung by a marketing department or the need to make a product that has mass market appeal or that works for pros. So whether you actually wind up with a product that's any worse than theirs is not foretold by your lack of a degree.


cleaning v-brake arms with riveted inner sleeve I've got avid single digit 5 v-brakes, those with an inner sleeve riveted into the arm; the sleeve isn't supposed to move around the pivot, the arm itself moves around the sleeve instead. Arguably due to the salt in the street snow, arms are not returning to open position, as described here and here. How can I clean and lubricate those sticky surfaces of the arm and the sleeve, which are completely hidden even after taking the arm off the pivot (i.e. between "A" and "S" on the second image)? WD-40 (Germany) was not good enough. And I'm no smarter after reading the manual (from www.sram.com/service/avid/70).

PS: feel free to edit my English, I'm having a difficult time with mechanical vocabulary...

I have had these brakes before, and what I've found to work is:

Take the brakes off the bike
Clean the bosses on the bike, inside and out with rubbing alcohol and a Q-tip (a.k.a. cotton swab)
Clean the portion marked in red with a q-tip dipped in rubbing alcohol. also clean the back surface of the brake (where the bolt is, but on the other side of the head in the same way). Be pretty thorough; you'll go through a bunch of q-tips until its clean.
Let the rubbing alcohol dry
Grease your brake posts and bolt, and re-assemble. I use regular old white lithium grease.

They tend to last about 2 years this way (but I think we probably have a lot more road salt and gunk in the Midwest USA than Germany), and then no matter what I did, I had to chuck them (which isn't a huge loss, they're pretty cheap).

The Single Digit 7's are more robust in this regard.


My Shimano Tourney RD-TY22 7–21 speed bike rear derailleur mech, direct attach has broken, need a replacement, preferably newer To cut a long story short, I have a full suspension mountain bike. Its rear derailleur mech (see title) is broken, had a trip round the spokes and age has degraded the main springs. I therefore need to replace it. Now, its old, and you can get the model, but its new, old stock so I want to upgrade the rear mech, not just replace.

So I need a Shimano rear mech, for 7 speed rear wheel, that bolts directly to hanger that is part of frame (Direct Attach). Can someone suggest how to select a  replacement mech? I am happy with the rest of the system, which is Dual SIS, and grip shift.

Thanks in advance,

Jawapower

Specific product recommendations are off topic here, but I can tell you that pretty much any Shimano MTB 7, 8 or 9 speed derailleur will work.

The reason for this is that the shifter controls the amount of cable pulled for each gear change. The derailleur has an 'actuation ratio' which is the ratio of lateral movement to cable length pulled. Shimano 7, 8 or 9 speed derailleurs all use the same actuation ratio and the shifters are responsible for pulling the correct amount of cable for the 7, 8 or 9 speed sprocket spacing.

Derailleurs from the Tourney TX (the highest Tourney level), Altus or Acera lines will be a step up from your current derailleur.

You will need to check the specs of the derailleurs you consider, specifically: the max largest sprocket that can be accommodated and and the 'total capacity' which is the  max (difference in size small and large chainrings) + (difference in size small and large cassette sprockets), measured in teeth. and represents how much chain slack the derailleur can take up.

Specs can be looked up on Shimano's site here: http://si.shimano.com/#/


upgrading gears to Shimano XT My bike is a ClaudeButler CapeWrath D24, with Shamino Alivio gears front and back. I was thinking it would be good to upgrade these to something like Shamino XT, at least on the front to start with.

1) Is this something I can do?
2) Can it be done incrementally?
3) Do I have to get certain rings to go with XT? Can I have alivio on the back and XT on the front?
4) Looking at Wiggle and searching for Shimano XT there are a lot of items.  Do I need the whole XT range, i.e. shifters, cassette, chainrings, front and rear derailers?

Is there a bit issue with doing this in bits, or just front or rear, or leaving the front shifters as they are?

Currently I have a 8ring cassette, can this be changed incrementally for a 9 or ten?

The shifting on Alivio is not as good as it could be, I am suspicious that Shimano do this deliberately so that there is a reason to upgrade to the Deore components.

You can put an XT derailleur on there, that will give improved shifting response and work with your existing components. Try changing the cables first as this is more likely to improve the shifting.

The front derailleur can be similarly upgraded.

To get nine-speed on the back will cost lots of money because the cassette is highly engineered (and not just bits of stamped out steel).

If you get your existing Alivio to work correctly by putting new cables in, fixing that front chain-ring and giving everything a good service you will be spending modest sums of money and getting good results. As for spending a small fortune on an XT groupset a piece at a time, I doubt you will be able to go that much quicker on it or the bike be that much lighter.

if you fix what you have and save the money that you would spend on XT then you will have a good deposit for your 'dream bike'. Couple this with a bike-to-work scheme and you might be able to actually afford it, with payments for the rest spread out over the year.

To take a car analogy, you could upgrade a VW Beetle to a Porsche 911 a piece at a time, starting with the transmission. However, this is a lot of work and the Beetle will never really be a Porsche. You would do better to replace with VW Beetle spares and save up for the Porsche instead.

Aftermarket parts always cost more than they should - add up the RRP for all the parts on your bike and it will cost twice what you paid for it. Going for the deluxe parts makes no sense with your situation - although Wiggle/Shimano would like you to believe otherwise.


Singlespeed chainline adjustment I have replaced the freewheel on my bicycle with a singlespeed. However, the chain line appears to move inwards from the rear to the front. picture

I have measured the rear frame spacing as approx. 127mm. picture I then measured the distance from the center of the freewheel (teeth) to the inside of the rear fork, which was 25.4mm. picture As per Sheldon Brown's website, the rear chainline measurement calculates to 38.1mm. I have measured the distance from the teeth of the chainring to the middle of the seat tube which is approx. 42mmm. Does the difference between the front and rear need to be within 1mm?

I think the only way I can achieve a straighter chainline is by removing the bottom bracket cartridge ring and placing a 2.5mm BB spacer from eBay between the ring and the BB shell. But I'm not sure this would work.

Alternatively, could I add a slightly longer spacer to the rear axle on the freewheel side, a shorter spacer on the non-drive side to move the rear chainline inwards and then redish the wheel?

Could you move the chainring on the crank arm?  I can't tell from your picture if it used to be a double or not? I have an old schwinn that I converted to fixed and had the exact opposite issue (chain line moved away from the bike).  I wanted the 52T large chain ring to stay so I moved it to the inner ring position.  This is probably not ideal, but I've had no issues in 10 years on it.


Why does my brake keep pinging out and almost killing me? My back brake (top picture) is clamped down, as it should be. The quick release on the front won't stay down. I have tried loosening the cables, tightening them, nothing works. As you can see in the gif at the bottom, it keeps springing back.

I've decided enough is enough. I braked hard while going down a hill and the front brake just pinged open. Not good. I didn't get hurt, but it's only a matter of time.

Why is this? What can I do? just get a new front mech?

That looks like the quick release mechanism used when removing the tyre to open the caliper a little wider.

It looks broken? - it should be tucked under in line with the pull of the cable. Since it isn't the cable is actually pulling the release open as you brake.

You might be able to temporarily remedy it by leaving it in the open position and pulling the cable tighter. You would however lose the use of the quick release. Probably not a great idea to run it like this - since the cable will be pulling on the fixing nut at a strange angle.
Best replace with a new caliper.


Can I use an 1/8" chain on an old 8speed I'm converting to single speed? I am in the process of converting an old road bike of mine into a single speed. I bought new crank arms, rear wheel (with a conversion kit), and a rear derailleur.
Do I need to use a 3/32" chain, or can I use a 1/8" chain that I see being used on all other fixies?
Edit below

the rear derailleur is because I have vertical dropouts on the bike, so this will be used as the chain tensioner

the new rear wheel with conversion kit is because the old wheel broke (this is part of the reason I'm converting it)

The new crank arms I bought have just one chain ring on them (similar to this)

Yes, you can use an 1/8" chain instead of 3/32", is the other way around you can't go.
However, it may have problems going through your deraileur, but we can't say for sure. For normal single speed or fixies that's not a concern.
I would use a normal 8 speed chain anyway, it'll probably be cheaper. Only get an 1/8" chain if you get track chainrings, or you want the colored chains, which I've only seen in 1/8" size.


Mountain bike tyres unreliably lose and keep pressure? I have a old mountain bike (10 years old) and for most of it's life it's sat in the shed (being ridden lightly maybe once or twice a year), only recently have I tried riding it regularly for the first time since ownership.
I have a really strange problem with the bike tyre pressures, sometimes whilst it has been in the shed they have gone completely flat and just sat there like that for over a year.  When I finally get round to riding it, I pump them up and they are good to go, however, sometimes after pumping them up they go completely flat the next day.  Other times, when I pump them up they hold pressure for months on end (if not years) without going flat.
What I found really strange is yesterday I thought my front tyre pressure was slightly low so thought I'd pump both tyres up nice and high as I'm mostly using the bike on the road now.  Pumped them both up, put the bike back in the shed.  Today, I go for a bike ride and the back tyre is perfect, solid, the front one is completely out of air.  So pumped it up again and went for a ride, half way on my journey it went completely flat again and so had to ride back on the flat.
Now I've taken apart the front tyre and pumped up just the inner tube, it's holding pressure fine for now, will do the water bucket test tomorrow, but there are currently no signs of leaks.
Does anyone have any idea why my front tyre can hold pressure for months on end and then after being pumped up it immediately goes flat very quickly sometimes (the back has done the same in the past).
Since I'm riding the bike more often, I really need to sort this as I am travelling further and further and it really sucks to come back on a flat.

Sounds like the butyl rubber inner tubes have perished a little, and you have either a very slow leak, or a valve that lets the air out slowly.
Just buy three new tubes from an online supplier - they'll cost about $5 each.  Two to fit, and one to carry as the spare.  You should also have two/three plastic tyre levers, a working pump, and whatever tools are needed to get a wheel off the bike.
The old tubes can be used to hold plants to stakes in the garden, or as a chainstay protector, or sliced up into rubber bands.
Also, I'd suggest having a close look at the tyre's surface, and decide if they're getting a bit old.  Rubber is attacked by ozone, UV, and heat, so if your bike was stored in a shed/garage then they can slowly deteriorate.  If you're doing strictly road riding then its a good chance to change to more efficient tyres too, compared to MTB knobblies.
Finally, check your brake pads.  Rim brakes have rubber blocks which can harden with age, so your brake performance can suffer.  Disk brake pads are not rubber so don't deteriorate in the same way.
These are all consumable items, so don't get put off by some costs.


Is it worth time to rebuild an old steel frame? I found an old Favorit racing bike. I didn't weigh it without all the parts but I find it pretty light, and it has a nice classic look. It is however really rusty (superficial damage only). Right now it's been rebuilt, and except for the very old and damaged crankset (which I'm going to change), it rides fine.

My question is: is it  worth it to repaint the bike and slowly rebuild it with higher quality parts? I'm not looking for the lightest bike, just a strong, comfortable and durable bike. Also, I like the fact that the bike would be unique and customized. Would I be better off buying a bike, or getting a better quality steel frame?

Buying parts alone is sadly a rather expensive way to get a bike and I doubt anyone would be able to tell you if it's worth it to you. That said, I'd be very tempted.

I like old bikes and it's better they get rebuilt and used than end up in landfill.

You should spec up the components you want/need and compare the price with a new one of similar quality and see which you prefer.


Can't get bike valve caps off I will sound a bit thick but i'm no bike mechanic, to give you an idea of what make my bike is here are some pics (the bike isn't mine and the owner doesn't know).

the problem is that I cannot get the valve caps off I tried twisting and pulling, pliers are a no no due to the bike not being mine, here's a pic, any help is appreciated, Thanks.

Quick edit
Just to clarify I've not stolen the bike,
I crashed mine and it's the beginning of summer and I really wanted to ride, the bike is my mother's and just needs some maintenance. Also I appreciate the answers I've tried using more force but the entire valve seems to turn and jam, no movement on the cap. Any ideas?

Turn anti-clockwise as seen from above and use more force. You should be able to get them off by hand.

If you do destroy the caps, go to a bike store and buy replacements. Ask for 'Schrader' type caps.

Can we assume you are borrowing a bike and need to inflate the tire? The statement 'the bike isn't mine and the owner doesn't know' is slightly troubling. If you have trouble with a borrowed bike take it back to the owner. (deleted as based on misunderstanding.)

Brand and model of bike does not matter, tube valves are either 'Schrader' (same as on car tires) or narrower 'Presta' types.


Deflated tube: Is it me, or it is the rim tape? I just had flat tube #4.
Enough is enough.

Please examine the photo of my rim and the valve stem hole. Is the rim tape too far off of the edge? I had inflated the tire with more air, per the first post's advice responses. It had been working fine for nearly a week now.

Suddenly, pssssss and it's a hole at the valve stem. AGAIN. Just like the last two times. So am I just not pumping it up enough -- but if so why did it last so long -- or is it the rim hole rubbing away at the valve entry area and eventually cutting into the rubber at the valve?

I don't mind pumping it up...I have to do it manually, and fear for overinflation and potential explosion...but I can certainly pump it to the proper volume, as I have been riding on this tube for several days now.

Rim strips, proper ones from a bike shop, last a long time and are immune to the wear shown on your picture. It looks like the strip left the hole exposed enough that the base of the stem was allowed to make contact with the rim.

My advice is to take off the rim tape. Clean the interior of the rim with acetone. Take some fine grit sandpaper (1600-2000 grit) and gently rub it into the hole from inside of the the rim. That will help smooth out any possible burs. Then install the rim strip (not tape) and for one last good measure use a tube that is one size smaller than you usually do. It is curious how the tape shifted. Perhaps the stem wasn't perpendicular. At any rate, the smaller tube would decrease the chance of this happening with no ill effects.

Good luck!


Can 27.5x2.2 tire fit in 27.5x1.90 rim? My bike rim is 27.5x1.90 is it possible to fit a 27.5x2.2 tire on it?

I assume you mean that your current tire is 27.5x1.90. Rim widths are defined by internal width and external width. Regarding the tire the internal width is important.

As rims and tires for mountain bikes are becoming wider and wider, rim manufacturer often specify the recommended tire width for a rim and tire manufacturer specify the recommended rim widths.

1.90 and 2.20 are very common tire sizes for regular mountain bikes. So they should fit the rim. But as Daniel already commented: you have to check if there is currently enough room between the tire and the frame or fork. Note that wheels and tires bend under load and may rub at the frame even if there is a small gap between tire and frame. Usually bicycle and fork manufacturer define a maximum tire width for their frames and/or forks. As the tire manufacturer are not that consistent with their tire size labeling it may not be the whole truth. It also depends on the size of the side knobs.

So maybe you find a max tire width specification for your frame or you just have to guess if there will be enough room for the new tire.


What is an attached bottom bracket? Reading the specifications of a Merida Reacto 500 (2015) I noticed that at the bottom bracket is Attached, I only ever read about brackets threaded in the frame or press fit brackets.

The Merida website list the crankset as FSA Gossamer Pro 52-36 386. FSA's web site show this to be a pressfit bottom bracket. Why it is spec'd as attached rather than pressfit I don't know. It is possible that this is how it was translated into English.


How to you remove the seal from a Deore XT FH-M8000 freehub? When first installing (or overhauling) Shimano rear hubs, I usually pull the freehub, lift the seal off the back side (where the splines are that engage the hub body) and then heat the freehub with a heat gun. When the old lube flows out, I drip in enough Phil's Tenacious oil to keep the things utterly silent. I love silent coasting. I have had no trouble doing this with Deore LX freehubs and others, but the FH-M8000 XTs I've got don't seem to want to give up the seal. Usually, gently picking the rubber seal with a large (not too sharp) sewing needle lets you pop it right off, but these don't seem to want to budge. Anyone out there pull one of these rear seals and know how it's done?

I would take the hub to your local bike repair shop. More than likely they will pull out a special tool just for this issue of your seal not wanting to unfasten itself.


The best way to mount a rear rack I've bought Bontrager Backrack light and I am thinking about different ways to mount it on my road bike.

Some details:

at the bottom the rack attaches to the quick release screw.
the tubes connecting the rack to the frame at the top are attached to the rack by a clamp as shown below. The clamp sits on top of a racks tube and the connecting tube is inserted through the holes. With tightening the screw we push the tubes together.
this clamp can be mounted on only one transversal tube, others are too wide.

I can attach the rack to the brake mount adapter or to a special seatpost clamp.

Questions 1 and 2

I prefer the seatpost clamp (pictures S1 and S2) since the brake mount adapter doesn't seem strong (I can rock the rack and bend the adapter, pictures B1 and B2).
Is there any downside to the seatpost clamp mounting, e.g. putting too much stress on that part of the frame?
Also, is the high angle of the tubes problematic?
The tube is only in an approximate position since I haven't bought the appropriate seatpost clamp.
The tube behind was left there from the brake adapter mounting.

Question 3:

Which orientation of the connecting tube is the best?
Obviously, I will cut the tubes to the correct length when done.

There is another option that is preferable to either of the ones you mention: P-clamps. These are small strips of sheetmetal bent into a P shape and covered with rubber. They fit around the seatstays to create mounting points. You'll be able to attach both of the top rack arms that way. This will be much more secure. P-clamps are cheap and you can probably find them at any decent bike shop or online store.

Once you've got P-clamps on, I would mount the top rack arms as pictured in B1, more or less, but that's mostly a cosmetic thing. B2 wouldn't really be different in terms of load transmission.


Are bikes more prone to punctures after a spell of rainfall/flooding? We've had an unusually wet winter and flooding has been a problem in my area. Now that the weather has improved and cycling is possible/pleasurable again I'm finding I'm getting many more punctures than I would normally. The kids too, on their bikes.

Is this just a run of bad luck or is there a connection with the wet winter? Has the flooding washed more debris onto the road? Perhaps this is a well known problem but I haven't noticed it before.

Yes, it's because the rain washes more debris onto the road which can then cause punctures. The wet tyres are also easier to damage (couldn't find out why but I guess because it softens the rubber)

Source: Bicycle by Helen Pidd


Is it possible to use road-style brifters with an internal gear hub? I have a touring bike with road-style Shimano brifters, which I love. I'm also very intrigued by internal-gear hubs, but these hubs seem to focus on rotary or push-button shifters.

Is it possible to run an internal-gear hub, especially one of the 11-, 12-, or 14-speed ones, with road-style brifters? And if so, what parts would be needed?

Based on the number of other people asking the same question around the internet, I suspect the answer is no.

This page contains the best wrap up I've found of available shifter options for Rohloff hubs.

Mittlemeyer may be bringing out some brifters that work with hydraulic brakes in September, but they've already delayed their earlier March release date.


I'm perplexed, why is my cloth rim tape not sticking? I have a pair of Velocity Deep V wheels (silver, from Velo Mine) and have a roll of BBB BTI-98 16 mm tape. I tried to apply it today and the adhesive will not stick to the rim. It just kept sliding. Moreover, the part of the tape that I attempted to apply to the rim no longer is as sticky as it was initially. What gives?

I've had rim tape before that didn't stick to the rim, but did stick to itself - which is all that matters really.  As long as the rim tape won't separate from it's ends, it's doing it's job, plus the valve will stop it sliding around.


what kind of grease to use on front shocks I have managed to release my shocks from the compressed position. The uppers look in very good nick. It has a little corrosion on the uppers.

I brought a tub of pure bike eco grease ages ago and never used it. Is it possible to use this on the uppers and lowers?

http://www.sjscycles.co.uk/pure-eco-range-bike-grease-100g-tub-prod29089/

It sounds like the fork was non-functional or stuck.  Simply greasing the uppers isn't going to resolve the problem - you likely need to rebuild the entire shock assembly, replacing seals, lubricating internal parts, etc.  Every fork is a bit different, so you'll need to find service instructions for the specific manufacturer/model you own.  Or, have the local bike shop do it - it shouldn't be more than a few hours labor.


Are convertible full face helmets as safe as regular ones? I'm thinking about buying a full face helmet for bike parks. While searching I found helmets like Bell 2R that convert from round enduro helmet to full face with a removable chin bar, which is kind of nice because then I'll get a fancy round enduro helmet 2 in 1. The only question I ask myself, are those convertibles as safe as a proper full faces?

Yes, some convertible helmets can be as safe as Full Face Helmets.

The safety standard for the protection of a full face mountain bike helmet is ASTM F1952 - Standard Specification for Helmets Used for Downhill Mountain Bicycle Racing. This covers the chin bar and a higher level of testing than EN-1078 (such as a higher drop height 1.2 to 1.6). En-1078 is the standard for road and trail helmets.

Purchasing a helmet meet this standards means they will be as safe as a proper full face. Choosing a helmet that doesn't hold the standard doesn't mean that it isn't as safe, but it hasn't been tested to that level and doesn't offer the same assurance. The standard has two levels, one for the chin bar and one for the helmet.

In order to get the same protection as a full face you'd need to find a convertible helmet that held both such as the Giro Switchblade. If you are happy with a trail helmet with a certified chin bar but EN-1078 certified helmet then something similar to the Leatt Enduro. If you want chin protection and not concerned by the standard then something similar to the Bell 2R, which simply holds EN-1078.

The reason behind the Bell 2R not holding the standard is suspected to be vents on the chin bar. Bell have said that they test to internal standards, which may meet ASTM F1952, but they haven't certified the helmet against the standard.


why does my front suspension have no spring or air valve I am riding a old rally mtb the fork is a xc100 , I can find no mention of these online, and it has never a spring nor a air chamber to make the suspension work. it is recently began to stop working so I wanted to tune it. however I am lost as to how it works.
any ideas would be most useful.

many thanks

ewen

i had one of those some years ago. you need to check for bolts in the bottom of the legs, if there are not any you must get a long 5 alen key (about 45 cm length) take out the upper caps and introduce the long key. once you take out tha bolts in both sides you will be able to disasemble the fork, then clean averyting, grease, and put everyting together again.


New hydraulic disc brake has less stopping power than old rim brake—why? Recently, I upgraded to a Rockrider 540 bicycle. My previous bicycle (a similar but simpler model) had rim brakes, this one has hydraulic disc brakes.

On the new bicycle, the stopping power of the front brake is clearly worse than on my old one. However, the rear brake works much better than on the old one.

Does this indicate a fault with the front brake, or does it just need some use before it becomes more effective? How can I fix it and make the brake work better?

Disc brakes commonly have issues when:

they are not bedded in yet. This is required on new bikes or new pads/disc only. The pads and the disc don't have the optimal contact surface established when out of box; bed-in-process;
they get in contact with lubricating substances. There are many ways to clean them, but mainly alcohol should do it; how-to-clean-disk-brakes;
they contain air mixed in with the brake fluid in the circuit. This is hard to detect and requires a full brake bleed. Generally there are low chances this is the case and even lower that both of your brakes have this issue. Checking if the braking power front-back is close to equal should reveal that.

If the disc is clean and there is no air in the circuit, there is no loss of power and that is the true power of your brakes. Tektro 160mm is a low end brake so that wouldn't be a surprise. A workaround is to try a bigger disk if the fork/frame allows.


Why would a bike feature a "carbon wrapped aluminum frame"? I saw a link to what appeared to be a Carbon bike on amazon.  The price was extremely lower than any carbon bike I had ever seen.  After reading a bit, it seems that the bike frame is really made of "carbon fibre wrapped aluminum". What advantages would wrapping an aluminum frame in carbon have compared to just a regular aluminum bike.  Is it just to get a carbon look bike more cheaply, or does it allow you to use a narrower aluminum frame, with carbon taking up some stress, creating a frame with a weight somewhere between carbon and aluminum?

That is purely marketing. It's a common ploy with components, but I've never seen it on an entire frame until now. Aluminum and carbon can be used in conjunction effectively, but not in this case. The carbon wrap on that bike is basically veneer. While Schwinn was once upon a time a well respected brand, they suffered a major fall from grace after going bankrupt. Their bikes, even their bike shop level bikes (i think they call them their "select" series bikes) target the budget market. They're not horrible, but they're not great either. The bike you posted a link to is no exception. One could argue that the combination of dissimilar materials would aid to vibration dampening, but that's really just more marketing jargon, at least in this case. That bike will still ride just like a full aluminum framed bike would. If you are considering that bike save yourself a few bucks and just go with a full aluminum frame.


Older rims, newer tires Can I put "new" 27 and half inch tires on "old" 27 inch rims?  Looking to
save the trouble of finding out!

Have not seen 27 x 1/2 tires before but the old 27 x 1 1/4 rim probably will not care if the width is greater.  One question is whether the wider tire will clear your frame.


Mountain bike suspension forks I am thinking about changing out the worn suspension forks on my quite old Specialized Stumpjumper which has rim brakes. I found some forks online (RockShox 30 Silver TK Fork: 26") and some of the specs listed I don't understand...
 - Brake type: Post mount 160  ??
 - Axle to crown length:487  ??
 - Steerer tube length: 265  ??
Pretty sure it will fit, but want to be positve before I order...
Dan

Brake Type: Post mount 160 is mounting points for a disc caliper and
160mm disk (You can go to a bigger disk with adapters, but cannot go
smaller than 160 with this fork)
Axle to Crown:487 - this is the fork length from axle to crown.
Ideally you would match the existing for within say 10 mm, as it
changes the bike geometry is the difference is too much. If
increasing the fork travel, you may want to increase the crown/axle
length to accomade more sag.
Steerer tube length -   the length of the steerer tube - the bit the
handles bars bolt onto. This is normally cut shorter to suit the
bike, make sure the length is not short than you existing fork.

These forks do not have mounts for rim brakes, so are not suitable unless you upgrade to disk brakes, which requires a new wheel as well as brakes.

What you must do is go for a 1/8" straight steer fork. The other thing to match as closely as practical is the axle to crown measurement, as this maintains the geometry.

If you upgrade the wheel and front brakes to disk, you have far more options. If you  do decide to upgrade to the wheel, you need to decide axle and if to go boost or not, along with wheel size.  You could probably go to 27.5" without upsetting the geometry too much, especially if you go to a shorter travel fork. Obviously this option adds significant cost

Unfortunately replacement forks for older bikes are getting hard to come by, 26", rightly or wrongly. has been consigned to the history books. While we do not do product recommendations, you are more likely to find a compatible fork from a lower end manufacturer such as Suntour (e.g. the Paragon - short travel but will bolt straight on).

In the end it may not be economical to do this. Consider sourcing a used fork from the late 2000's - however finding one that is not worn out will be hard.


Tights, Shorts, and Padding I have a pair of the MEC Roubaix tights, and noticed they don't have any padding.  Not a big deal for short rides, but...

Are you supposed to wear [spandex] shorts (with padding) underneath?
I went for a roadie group ride, and noticed they were all wearing tights (much thinner material), but under the spandex shorts.

The "padding" AKA chamois is a vital guard against chafing-related injuries for anyone who intends to ride appreciable miles on a bike, and I would highly recommend wearing some garment with a chamois for any ride you do.  For cold weather riding when simple shorts do not suffice, there are a number of different options.  You can:

Wear proper cycling shorts under your chamois-free tights.  This provides you with an additional layer of warmth without sacrificing the protection a chamois provides.
Buy leg warmers to complement your cycling shorts.  Leg warmers are just an insulated sleeve that goes over your leg and runs from the ankle to just below the crotch.  When you say you spotted other cyclists wearing tights under their shorts, it is much more likely that they were only wearing leg warmers.  This provides them with the added leg protection, without a layer of material in between their body and the chamois.
Buy tights with a chamois.  These are designed to fully replace your shorts, rather than complement them.

Riding any extended distances without a chamois is ill-advised because of the numerous health complications (that's a very bad part of the body to develop open sores), and when you do wear a chamois, it should always be the innermost layer, adjacent to the skin.  Whatever else you wear to keep your legs warm just depends on your budget, the temperature, and what you find comfortable.


What parts do I need to use Di2 wireless shifting on a road bike Also what is the cheapest best way to buy them. I just want everything that is absolutely necessary for wireless shifting so no crank, drive chain breaks etc.

You require these items, all DI2 compatible:

rear derailleur mechanism
di2 controller box (normally strapped to the bottom of your stem)
di2 brifters, or di2 shift buttons that strap to your handlebars, but mean you can keep using your brifters as plain brakes.
battery (one for a wired system, or several for a wireless system)
wiring harness, and secure method of holding wiring on/in the frame so its protected.
wall charger (maybe USB based, maybe a separate wall charger)

You probably require

front derailleur mech unless you want to make it a 1x bike

For your testing, you really will need a road bike too.  The derailleurs will try to calibrate themselves and may go into fault mode if there's not a cassette or chainring detected.   So that means a modern cassette with 11 gears, maybe 10 (I'm unsure on this point)

Generally speaking, the whole groupset will cost about the same as a bike with that groupset fitted.  Used bike gear drops in price very fast too, so don't think you'll get your money back by selling it on after the testing, even if its never been ridden.

An alternative suggestion might be to make contact with the Shimano distributor in your area and see if you can get access to test/demo kit for your purposes.  As long as you're not cutting out a reseller, they might be happy to talk.  Or involve a LBS