Seeking information on this Raleigh I've been given this bike that needs attention.  I have found no information on the web about a Raleigh "The Mission" bicycle that matches this type, though there's lots on the more recent rock hopper.  I'm wondering about its age, make up, market, -any information really.  It looks like it might make a good commuter for a small adult, which I'll have on my hands soon.

I'd guess late 90s for this bike.  Reasoning:

The overall look of the frame is small diameter tubes, which implies steel.  You can check this with a magnet.  Aluminium frames of the day were rather oversized by comparison.  It appears to have aluminium rims though, which is good, better for braking than steel rims.

Its a rigid fork so was never intended as a hard-core MTB.  The fork doesn't have a crown as such, instead the tines (legs) are welded straight to the steerer, giving it a curvy-hips look just below the headset.

I can just make out mudguard/carrier mounts at the rear dropout (fender and rack) so it has commuter features.

There's a quill stem, which is perfectly functional, but these days only low-end bikes have quill stems.  Most have moved to threadless.

The cantilever brakes will be fine once adjusted.  Given the age, you'll want to consider new pads, and possibly replace the inners and outers.  Canti brakes have a straddle cable which should also be replaced.

Its got a wide-range triple crankset on it, where the granny chainring is about half the tooth count of the big chainring.  Not a bad thing.

To make it a commuter - first size it to the rider.  That may mean replacing the seat post because it looks awful short to me.

Do put some air in the tyres - that back one looks quite devoid of atmosphere!

Consider removing the barends - they are known for catching things and stopping the bike in a hurry.  Vines/branches, people, cars, other bike's cabling or bars and it can all lead to a quick accident.

Lastly, a commuter should have decent mudguards/fenders in any climate that experiences rain.  Consider fitting some, as well as lights and reflectors.


Does USAC Allow Natural Suppliments? I'm a non-competitive cyclist that wants to try a few Cat-5 USAC races for fun; unfortunately, at 40+ years of age, I'm taking more than one natural OTC supplement to self-medicate.

Is there an easy way to tell which supplements are okay and which aren't?

I looked at the WADA List, but that list looks a bit intimidating to me.  I also took the effort to email USAC [1] and USADA directly and they said in their own words that the supplements I take are probably okay; however, some such supplements often contain extra bonus substances that might cause a positive on an anti-doping test.

[1] - Actually, USAC just told me to contact USADA.  USADA was the organization that actually "answered" my question.

I think you're looking at the lists backward - they have lists of banned substances.  Everything else is okay and permitted because its not banned.

So if your medication contains anything on the banned list you're best finding an alternative or dropping that product completely.

You're able to prove that you made inquiries, and that your supplements do not list anything on the banned lists.  You've done all you can short of getting your supplements chemically analysed, which is a bit extreme and unreasonable.

Imagine if you did get hauled up for having something in your test results - you have made more effort than most, and you have the paperwork/papertrail to prove it.

Just focus on your pre-race training, pre-ride the routes if at all possible, and plan your diet for before and during the event.  And plan on tapering nicely.


Loud metal sound when not pedaling I have a very simple city bike. I have neglected it outside for a while to a level I had to take it to a repair shop manually because of a blown tire. At the shop the tire was changed and the breaks readjusted.

But now when I am riding it I have a very loud cranking clanking sound (like the chain is hitting something, or something similar, don't know where it comes from) coming when I don't pedal for a few meters (for example going down a hill). It will go for a few more meters and stop, and then again.
It barely happens when I am just leading the bike with my hands (it will continue if this sound started, and I got off the bike for a while, but then disappear), it also doesn't appear when I pedal.

I can't find the source because the sound is only on when I am on it and disappears when I am off it.

What could it be?

Thank you

If I understand well this noise only happens when the wheel is rolling and you are not paddling. If so, then the most obvious place to look first is the freewheel. It is in the back wheel axle.

You can try to reproduce the noize by lifting the back of the bike and spinning up the back wheel with the pedal to a high rotation.

One cause could be the lack of grease/lubrication which can make the freewheel noisier.


1976 peugeot 10-speed bike correct tire pressure? I have a 1976 peugeot 10-speed bike. What is the correct tire pressure? I ride over concrete sidewalks and rough, pitted asphalt roads and paths.

First, and especially with a tire that old, check it for wear.  If it's cracked and dry-rotted, replace it.  If there are visible rips in the sidewall, also replace it.  If neither of those are the case, look at the sidewall of the tire.  Most tires should have a PSI recommendation molded in the rubber of the sidewall somewhere.


Does anyone patch inner tubes anymore? Many years ago I bought a 100 pack of REMA round patches from Amazon.  And back then you could buy patch kits for $1 that had a few patches, something abrasive to sand with, and a tiny tube of vulcanizing glue.
It wasn't a good idea (in my experience) to buy anything bigger than a tiny tube of vulcanizing glue (unless you patch many tubes at a time) since the whole thing usually dried up after being exposed to air.
So nowadays you can't find those patch kits as cheap as $1 anymore and I'm noticing that places like Wal-Mart can sell inner tubes for as cheap as less than $5.
So unless anyone knows a good source of where to buy those tiny tubes of vulcanizing glue, I'm thinking it's just more cost-effective (and trouble-free) to just go w/ new inner tubes instead of patching.
What do you guys think?

Yes, some people still patch their tubes
I've worked sales at a bike shop for three years, and patch kits are still one of the most common small items for us to sell. It still makes sense from an money perspective--a patch kit is $2 and can fix 10 tubes, while tubes are $10 dollars each (for good ones, at least).


Can anyone id this adult tricycle? Can anyone id this tricycle?  It has been painted over.  It used to be a sky blue color. The tires are 24"x 1 3/8ths".  My friend who gave it to me said it's at least 20 years old, but I think it's actually much older than that.  I'm planning on restoring it so any info would be awesome. Thanks!

I found out that the trike is a 1975 Free Spirit.


Do fat cyclists bonk? (this isn't a discussion on the attractiveness of large cyclists and likelihood of sexual congress...)

In my cycling career I have varied between 22 stone and 15 stone. At 6'2" the leanest I have ever been is still over 20% body fat.

I am not sure I've ever bonked...

My normal cycling day is an 18 mile ride into work before I have eaten or drunk anything. I have a yogurt granola thing for breakfast and salad for lunch. Some fig rolls mid afternoon then cycle 18 miles home.

I have done 80 mile training rides and really not eaten anything much.

I do sometimes feel tired and a bit weak but I thought that bonking was worse than that.

I assume that as I carry quite large energy reserves around with me that I don't bonk.

Bonking occurs when your body cannot metabolise stored fat (and muscle protein) fast enough to replace the glycogen reserves, you deplete the reserves in your muscles and liver, and eventually you run out of glycogen. Fat conversion requires high levels of oxygen, and is slow, so once those reserves are gone, your blood sugar plummets.

I suspect your body has adapted to your regular routine of 18 miles, after an overnight fast, on an empty stomach. You will not only have large glycogen reserves, you will have also adapted to convert fat efficiently while exercising.  Therefore, your observation of what happens for you is based on how you body responds to exercise rather than the amount of fat you have in reserve.  Additionally, 80 miles is only twice your daily commute distance (presuming you ride home), so its not a big increase over your normal weekly workload.

Even the slimmest person has more than enough fat to keep them going provided they are exercising at a level that fat conversion can keep up with. Therefore "bonking" or not is less about how much fat you carry and more about how adapted you are to endurance sport.

Another aspect of this is how fast you are riding. If you are riding at your aerobic threshold, as people who are racing do, you will almost certain bonk on an 80 mile ride unless you consume food, however, if your 80 mile ride is a leisurely pace and you can hold a conversation (implying plenty of blood oxygenation), you probably won't Bonk.

Don't give up hope of ever experiencing it. One day, it will happen. :)


The piston on my Avid Elixir 5 brakes popped out. Does the caliper need to be rebuilt? One of the pistons popped out of the caliper on my Avid Elixir 5 brakes. Can I just put the piston back in and bleed the brakes and then they will be good as new, or do I have to rebuild the whole caliper?

sram has always been awesome about providing excellent manuals for their products.

http://cdn.sram.com/cdn/farfuture/5Pyt9L0OIUi7XDfIWNl65p9qoT3H9ULX2vOahNqzavo/mtime:1330363328/sites/default/files/techdocs/elixir_5_service_manual_rev_b.pdf

I would recommend a quick rebuild to make sure the seal for the caliper isn't damaged. See page #19 of the above PDF.

Should be easy, just be ready to bleed your brakes ... ( a pain with elixers ... sorry!)


How do I obtain a duplicate bike key for my kryptonite U lock? I want a duplicate key for my Kryptonite U-lock. I have the key number.

Where can I order an additional key that will work?

You can get another key for your lock by ordering it from Kryptonite at this link.


How much better are aerodynamics between a vintage road bike and a top of the line aerobike? (Just up front: (1) All comparisons made keeping all other factors equal! (2) I know this is a really hard comparison, but there seems to be virtually nothing canonical on here or the rest of google, so I figured it was worth a shot to ask.)

Currently I own a beautiful 80s Gazelle, full chrome, steel frame, on which I occasionally do trips of various distances. I'm struggling to cycle faster than 36 kph avg on it (no aerobars) over say 100k. I have an 8 speed, and I believe my highest gear is 12/54.

Because of this I'm thinking of making an upgrade to a proper aero bike, I think it might make a difference. But how much of an impact can I really expect? I'm looking at the Canyon Aeroad CF SLX 8.0, which I might fit with ENVE 7.8 racing wheels - I'd say that's about as aero as it would get. What kind of (rough) speed improvement can I expect?

The bike's proportion of total air drag is roughly 20% (for a road bike, more for a TT bike as the rider assumes a more aero position), with the rider accounting for the balance.

So assuming exactly the same bike fit and rider position, then even if the new bike halved the drag coefficient of the old bike, it would mean a drop of only ~10% in your total coefficient of drag.

A 10% reduction in CdA, while a decent improvement, would result in ~ 3.4% increase in speed on flat terrain.

So a bike with 50% the drag coefficient of another results in ~ 3.4% speed gain.

If the aero differences of the bikes are less, then of course the potential speed differences will be quite small. What is significant of course depends on how much a given speed gain matters to you.

And just to set an upper limit to speed gain from changing bikes (same bike position), if the bike had zero drag (impossible of course) then you'll still only attain a ~ 7-8% increase in speed. That's the approximate theoretical upper limit.

If the new bike fit is aerodynamically worse than on your current bike then you may even go slower!

So while a nice aero road bike, assuming same bike position, will result in some speed gain, the bigger bang for buck is attaining a more aerodynamic position on the bike. As others have commented, this is often done with the use of aerobars fitted to the front of the bike to enable the rider to attain a much more aerodynamic bike position.

Of course you can do both and have fun trying!


Is this a good road bike frameset to consider building for a 5'6" rider? Can this frame be used to build a decent road bike for someone 1.73m (5.6 feet)? It has 58cm ST, 58cm TT.

7005 aluminum Easton Ultralite aero tubing. 1" aluminum threadless fork.

I'm coming from MBX and never even rode a road bike :)

What are the things i should look for? nothing too indepth, just the major mistakes i can make when starting with a frameset.

For one thing, is a 15yr old aluminium aero even a good choice these days?

Given the age of the frame, it's limitations in terms of component choice, and the size of the frame compared to what I would expect a rider of the height described by the OP to ride, I would say building this frame is a waste of money and time.

For a rider who is 5'6" tall, a typical frame size is 52cm. This frame is a 58 cm, 3 sizes large. Even if you have an unusual body type which pushes you to a larger than average frame, unless you are wildly out of proportion, you will not move up by 3 frame sizes.

In addition, since the frame is alloy, and 15 years old, at least, there is the issue of metal fatigue to consider. While many people ride alloy bikes which are 10 or more years old, the useful, efficient life of an alloy frame is typically 5 years. Had you owned and ridden this bike for 10 years, so that you were familiar with its limitations, handling, and perhaps attached to the frame sentimentally, I might consider rebuilding it. Since that is not the case, I would not spend the money to build a frame with no useful life left.

And last, if you build this frame, it is likely that you will have difficulty sourcing properly sized parts, or will have to compromise with shims and adaptors to make the build work. I know that 1" stems are getting rare, and it's possible that the axle width on this frame is narrower than a typical modern road bike, although that is only guesswork.

All in all, I see many reasons not to build it, and none to go ahead. But at the end of the day, it's your bike, and your body. You will need to decide for yourself.


What is this headset's name per the Standardized Headset Identification System The Park Tool website has a page describing the standardized headset identification system.
I would like to confirm that I've understood it properly. Is this bottom  section of a press-fit headset shown in the picture a ZS56/40?
NOTE: I've taken measurements with inexpensive digital calipers and the fractional component of the value can change significantly depending on how much force is applied when turning the thumbwheel.

Yes ZS56/40 - Zero stack with 56 mm bore diameter and 40 mm fork crown race.
It is zero stack because it is a black cup containing the silver bearing, but the bearing ends up inside the frame tube (i.e. not external). The 56.10 mm dimension gives a snug interference fit with a 56 mm head tube ( bore diameter). The 39.95 or so is about the 40 mm dimension that interfaces with the crown race/steerer tube. That last measurement seems slightly tight but possibly measurement error, tolerances aside it would be called a 40 mm.


Lacing wheels Hope Wheels one a enduro synthesis alloy rims Could anyone tell me the spokes I would need for a Crank Brothers enduro synthesis alloy rim for a 27.5 and a pro 4 disc hope hub 148 mm boost rear wheel 3 cross. I have built a few wheels and pro wheel builder said I would need 273.3(I rounded up to 274) for the left and 272 for the right but every other spoke was way to long so I tried 272 for both sides and every other spoke was way to long as well. I have checked my 3 cross lacing pattern multiple times and from what I can tell I am not doing anything wrong so I figure it has to be the spoke size.So if anyone could potentially point me in the right direction id appreciate it. ( i am using 15mm spoke nipples)

If I measured the rim to be an actual ERD of 564 (the published number) with the nipples I was using, this is what my calculation would look like using the raw formula via Spocalc:

From there I would choose 271 for my right length or 270 if that wasn't available, and 272 for my left or 271 if that wasn't available. The rouding down by those amounts is to compensate for spoke stretch and rim compression. Never round up.
Your problem could be occuring because published ERDs usually are based on 12mm nipples. Longer nipples typically have longer threaded sections, so they can make a spoke that would be perfect for 12mm instead bottom out on the threads with a longer nipple. This issue is real but a detail that gets left out of too much written work about wheelbuilding.
Cut to the chase and measure the ERD yourself. Take 2 spokes of known length, poke them into the rim 180 degrees apart, then take 2 of the nipples you're using and screw on the nipples until they're at the point you want to define as ideal thread engagement. With 12mm nipples, that usually means the tip of the spoke flush with the top of the nipple, but with longer ones you have to choose how you're going to define it yourself. Usually what I do is screw the spoke all the way in and then back it off two rotations or 1mm, which for most spokes is 9mm of thread engagement out of 10mm of thread on the spoke, or thereabouts. Take your vernier caliper and pull the J-bends tight together with the jaws, then take the measurement of the caliper and add it to two times the spoke length. That is a method for measuring ERD that is superior to all commercial systems because it automatically accounts for any quirks of the nipple you're using, which is done virtually or not at all with other systems such as the Wheelsmith tool.
This measurement will likely give you a number that accounts for your long nipples in a way the published number isn't. You will probably plug it in to a spoke calculator and see what's going on immediately.


Correcting An Inverted Recessed Mounted Caliper Brakes On Vintage Bike Frame It seems like the previous owner of my bike installed the rear brakes backward. I figured I could simply mount the brake on the other side. Unfortunately, this is not possible since the recessed nut only fits on the wrong side. I'm unsure if I should leave the brake backwards (as-is) or if I should enlarge the inner brake hole and mount it correctly. Although the curved washers should hold everything in place securely, I'm afraid the outer brake hole will leave some wiggle room. What do you think?

I believe they did it this way since it takes a right-angle drill otherwise.
The clean way to do this is just use a front recessed mount brake and install it non-recessed. In some cases one can also find and transplant pivot bolts to make this work. Here since the back side has now been drilled, it would be easy to imagine problems with the brake slipping around if the recessed nut wasn't where it is. Conceivably you could take up the space with something else, maybe an aluminum presta grommet, and then put a front on it. Unless the looks are really bothering you, leaving it is probably best.


My SRAM X3 rear derailleur will only shift to the lowest gear but won't shift back higher The rear shifter is new and the shifters work smoothly but only can shift to the bigger sprocket and no matter what I do the shifter doesn't shift back to the smaller sprocket.

I don't know if this affects shifting, but my bike's cable housing used to be in several parts but now I made only one housing.

Highly likely that friction or pinching of the cable in the housing is preventing the derailleur spring from pulling the cable when shifting from large to small sprockets.

Remove the cable from the derailleur, With the wheel out and the cable detached check that the derailleur moves freely.  Pull gently on the shift cable (you may need pliers to hold on to it) and work the shifter, on upshifts the cable should pay out smoothly with little resistance.

Check the shifter cable housing run for kinks, tight turns etc.


Triple vs Double chainring? I'm bike shopping for my first road bike, and I've asked for a lot of advice from my father who was a serious cyclist once upon a time.  After showing him one prospective bike, he dismissed it with a simple "you don't want a triple" with zero explanation on why.

What are the pros and cons in having a Triple, vs having a Double crankset?  Does it differ from road bikes, to mountain bikes?

The idea used to be that a triple was just a double with an extra small, 'granny' ring (i.e. only grandmothers would need to use that one) so there was definitely some snobbery in a triple; that it was designed for those who needed a little more help. So on the club training run, you might be teased for it. (Google for 'triple granny ring' for various forum discussions and banter; don't worry, most of the responses are SFW.)

Practically, what it tends to mean is not necessarily a bigger gear at the top (i.e. big front ring & small back ring) but a much lower gear at the bottom, for the hills. So with the same rear cassette you might compare a 50/34 double for a 50/39/30 triple (although a 50/34 is probably more what is called these days a 'compact'). That range of triple combined with a typical rear cassette of 12-28 would work for most hills.

You also get a lot more options; so you'll get the similar effective ratios in several ways, because the ranges on the big ring overlap more with the middle, and the middle with the little one. Also, the gears are closer together - so you're more likely to find something that works well at the right time.

It is also easier to change on the front ring of a triple, on a compact you'll often need to change down a gear or two on the back when you move on to the bigger front ring, which means the chain is being yanked both ways and strained that bit more. But on the triple, you're not as far away, so you'll often not need to change the back at the same time as shifting the front.


Properly locking on a floor mount rack with a U-lock I have read recommendations to lock both the bike's frame and wheel. That's quite easy to do on larger racks, such as Sheffield stands.

The place I work in, however, has a floor mount rack to store bicycles, with semicircular shaped supports. If I park the bike with the rear wheel on the support, the derailleur gets a bit bent, which I believe may damage it (am I wrong?). If I park it with the front wheel, my U-lock will only manage to lock the wheel, which is not a good choice since it's quick release.

Under these circumstances, is there a technique to securely lock it without damaging the bike?

The rack I mention is similar to the one below, but it has no bolts.

In a situation like this, I usually don't fit any of the wheels in the support; instead I park the bike over the rack and just to the left or right of a loop, so that the lowest part of the frame is in close proximity with the loop. I then lock the frame and a wheel with a single cable (a U-lock might not work). Alternatively, you can place the rear wheel next to the loop (with the loop on the left side so it doesn't clash with the derailleur), and pass the U-lock through the wheel, straddling the chainstay and thus locking the frame as well.

In short, just forget about the fact that the rack is designed to accommodate a wheel in a certain way. Use it as a piece of metal you can lock your bike to.

Keep in mind though, that by parking your bike next to a loop, instead of in it, you're taking a bit more space and making it a bit more difficult for others to park. Something to bear in mind if the rack is often full.

Also, as others pointed out, that doesn't look like a very secure rack. That doesn't necessarily mean you shouldn't use it; you choose how well you want to lock your bike depending mostly on how common bike theft is in your area, how attractive a target your bike is (especially in comparison to other bikes similarly locked), and how much risk of having to replace it are you willing to accept. I lock my bike on a rack just like this every night, but it's on a communal yard, not right on the street, and the bike is cheap.


Why are single-speed bikes with disc brakes hard to find? I've been looking around for bikes (decent frame & components), and find that hybrids do have disc brakes (hydraulic), but are never single-speed. While single-speed bikes typically have linear-pull brakes.

Why is that? Anything in the mechanics that would make the two incompatible?

(In my case, I'd only want a disc brake on the front — for commuting.)

Usually, singles need to have horizontal dropouts so you can take the chain slack by adjusting the rear axle position.

That means that any brake that is attached to the frame will "go out of position" when you adjust the rear axle position. That is, by the way, the reason why some horizontal dropouts are not quite horizontal, but diagonal: to be near-perpendicular to the seat stays where rim brakes are attached, so that wheel movement is "tangential" to the brakes.

Unfortunately, with regular disc brakes, this adjustment would totally misalign the brake pads relative to the disk, if the adjustment is possible at all.

Although there are some bikes with grooves for the disk caliper, where you can "slide" the caliper into, it's usually not worth the trouble, because chain slack has to be corrected very often, and caliper setup is relatively laborious.

Also, it would be possible to take the slack with an eccentric bottom bracket, but that is even more esoteric.

Next to that, some single-speeds will come with a flip-flop hub. A flip-flop hub and a disc brake doesn't go well together.

Hope this helps.


Are v-brakes universal in size (kids vs adults)? Took my 5-year-old out for a ride today and the front brake pipe / noodle (?) popped out of the folded steel retainer. The retainer (not sure of the correct name) was splayed open and definitely needs replacing. Had to do a temporary fix.
I would like to avoid a cheap / low quality replacement and purchase brakes of a standard I'd expect to see on my own bike, and in any case it's getting plenty of use as he can now easily do 15+ miles. As it's only a small bike (Frog 43 with tyres labelled 14 x 1.5") I'm unsure whether I should be looking for v-brakes specifically made for a kids bike. The same question would apply to the brake pads they may come with.
I'm guessing Shimano may have something suitable. I'm UK-based if anyone has a direct suggestion.
Update: measured arm length at 108 mm centre-to-centre.

They are universal except for a very few models called mini V brakes, which use short pull brake levers as opposed to long pull. These stand out as having very short arms compared to most.
Shimano and Tektro make a lot of the good economical repair v-brakes. The model numbers change over time.
Reworking splayed out noodle cradles is a pretty common repair. It usually happens more from people getting frustrated and being rough with them than any kind of material weakness, so it's not likely to do the same thing again. I do it using either a slip joint plier or a Knipex plier-wrench. Of course I could imagine it being mangled enough that replacement is more prudent.


Where can I find a complete table of sprocket and with chain/hub/sprocket spacer width combinations? For example:

number of speeds  chain width  hub width  spacer width
1
5
6
7
8
9
10
11

There are various tables (for example on https://www.sheldonbrown.com/cribsheet-spacing.html) but I haven't found one with all the data, showing what combinations are possible.

The simple table you are looking for isn't really possible to compile. There are differences in what Shimano, SRAM and Campagnolo do, and road and MTB drivetrains have increasingly diverged. You can see that on this page that has a table of sprocket pitches (distance between sprocket centers) and the Sheldon Brown table here. 12 speed systems have diverged even more.

There is not really a one-to-one relationship between hub width and number of speeds. Older 5 and six speed hubs were either 120 or 126mm wide. Modern road bikes went to 130mm (on rim brake bikes) to accommodate up to 11 speeds, wider widths are driven by disc brakes and rear through-axles, not increasing numbers of sprockets in the cassette. Same kind of deal for mountain bikes, but with wider widths.

This page gives chain widths for 7 through 12 speeds, it's generally correct although I'm a bit skeptical about the actual chain width figures. I'm fairly sure there are differences between road and mountain chains.


Planting a foot when cornering: when and how? Recently I have noticed the following. When doing extremely tight turns e.g. 90 degree trail turn, I tend to:

Get out of my high saddle, position in front of it and low over the top tube
Stick the inside foot out, a couple of inches over the ground (easier on concrete, because it is smooth).

I have always thought of cornering as a trade-off between speed and safety. So doing the above, I feel safer, and am thus able to pass at a little more than walking speed.

One of two things can happen:

Because my center of gravity is now lower, the bike is tilted, and virtually all my weight is on the outside pedal, I make the turn.
Because I have entered the turn at too high speed, one or both tires begin slipping. I "fall" onto my foot, stepping firmly. As now all my weight is on the foot, I can "pick up" the bike and swing it around me in a crazy tight turn, then jump on it, while still moving.

My questions:

When is this appropriate technique and when would it be disaster?
What is the correct procedure for executing a planned foot plant?

Conclusion:

After I tried this on the trail a couple of times, my opinion is that planting foot is very different on smooth pavement and in rough terrain.

On smooth, but slippery pavement/ice, I can plant the foot momentarily, knowing that I will fall/slide out. The resulting acrobatic maneuver seems to increase the maximum possible speed in situations where no other technique would be appropriate.

It's a pity that I don't have a picture of the place this thing is helping me. Basically, it is a part of my commute, and is a steep-ish ramp, with two 90 degree turns, which in winter is wet, snowy or icy. As I need to stay upright, this technique is pretty much all that can be done on those corners.

On the other hand, planting a foot while going down the trail is radically different. This is because on smooth surface, on can put their foot out, parallel to the ground, and very close to it, so as to anticipate slide-off. On an off-road terrain this is not possible and dabbing seems to be confined to "free get out of jail" functionality when you realize the "oh shit!".

Thanks Tyler Jandreau and Aaron!

While a "dab" isn't exactly the most graceful of techniques it's useful to save yourself from a spill or wipeout. What you need to ask yourself though is whether you leave a foot out because you're not sure what's going to happen when you turn or because you plan on going fast enough to slide around the turn. Sometimes the slide is unexpected and should just quick plant a foot and move on.

On the other hand, you're going to get a bunch of trail builders and riders who say that any slide is unwarranted and damages the trail. Generally this is true, but hardpack trails with dust on top or a little gravel are very easy to slide on and don't damage the trail at all. Mud, loam, and other loose soils are more prone to being disturbed by excessive sliding.

As for the proper technique for a dab, it's very dependent on your riding style. Here's a general breakdown of the timeline for a turn:

See the turn: Look ahead and see a tight/loose corner. Begin evaluating how you want to take it (eg. at speed, slow and upright, or sliding).
Begin the turn: Lean the bike towards the inside of the turn, pushing your weight to the outside pedal. Keep your inside foot relatively light.
Back tire breaks loose: Knowing when this will happen requires experience with your tires, so practice sliding in a parking lot or gravel road.
Plant foot: Remove your inside foot and place it slightly ahead of where you currently are, in the direction your moving.
Push through the turn: Push a bit with the inside foot, kind of a cross between a kick and step. This should keep your bike position or possibly move you a little more upright.
Re-engage and continue: Plant your foot back on the pedal and pedal out of the corner.

And that's more-or-less how it's done. Watch a bunch of Trail/AM/DH riders do it and you'll get a sense of where in the turn you should expect a plant.

Last bit, as you get more confident riding push more speed into the corner. You'll find that some spots where you previously needed to dab, you'll clear no problem due to the added force keeping your tires in place.


How close do riders follow their wheel/attack How close do peloton riders typically and strategically follow each other's wheel/attack? Also, how is this distance manipulated in order to allow for strategic movements or a more aerodynamic ride.

How close do peloton riders typically and strategically follow each other's wheel/attack?

At the higher levels of racing you are often try to tuck your wheel as close as you you can stand, usually within about 2 inches of the rider in front, depending on how much you trust the rider in front. If you know they are  sketchy you will allow more room to compensate for their instability.

How tightly you draft also depends on where you are in the peloton. The front of the peloton is always the most stable, making it easier to draft tightly, while in the latter half of the peloton you suffer from things such as the  accordion effect where changes in speed at the front of the peloton become amplified as it propagates backwards in peloton. This can make it harder to draft closer, but you also have a much bigger draft effect (see details below) so you  don't need to draft as tightly as in the front of the peloton.

  Also, how is this distance manipulated in order to allow for strategic movements or a more aerodynamic ride.

Strategic movements are often trying to break the draft, see How to prevent drafting?

Getting more aerodynamic means either getting tighter to the rider in front or ensuring you have a number of riders in front and to the sides of you to maximize your draft.  A recent study showed that the draft in the belly of the peloton can be enormous, below is an excerpt from their results section discussing of their wind tunnel testing of quarter scale models with force transducers. They estimated cyclists in the belly of the peloton experience a 90% reduction in drag (i.e., 10% of the drag as a solo cyclist)

  Fig. 13 shows the measurement results for the nine cyclists in terms of percentage drag of that of an isolated rider at the same speed, i.e. the quarter-scale wind tunnel model tested at 26.7 m/s. It is shown that all nine cyclists benefit from riding in the peloton, even the leading rider (R1), who experiences a drag reduction down to 84% that of the isolated rider. This is caused by the subsonic upstream disturbance by the 120 cyclists drafting in his/her wake. When moving downstream in the peloton, the drag rapidly decreases. Rider R3 only has 35% of the drag of the isolated rider. This value corresponds quite well to that of the trailing rider in Fig. 9b considering that (i) rider R3 has an additional benefit by the 116 riders drafting behind him/her and (ii) the diamond configuration has a larger spacing between the rows than Peloton A. The last four riders, R11 to R17, have a drag force that is below 10% that of the isolated rider.

  Figure. 13. Results from wind tunnel measurements: drag of the nine cyclists in the vertical centerplane as a percentage of the drag of an isolated cyclist riding at the same speed.

  -- Aerodynamic drag in cycling pelotons: New insights by CFD simulation and wind tunnel testing

While you can get a massive draft in the belly of the peloton, the drawback is that you will not be able to respond quickly to attacks due to there being layers of several riders between you and the open road.  As such, a breakaway group could easily form while you are stuck back in the peloton.  If the break turns out to be the decisive race maneuver, then it didn't matter how much energy you were saving as you missed the critical opportunity.

Strong riders therefore will often sacrifice a bit of energy savings to ride near the front of the peloton so that they can control the race and respond to attacks.  While minimizing energy expenditure can be important, it is one of may factors that need to be optimize simultaneously. A racer just need enough reserves to cross the finish line, anything extra was wasted!


Saddle: how good is narrow? I’ve had a Brooks B68 for a few years now. It’s 205 mm wide; I have a fairly upright riding position; my back is about 25 degrees off the vertical.

Before choosing it I read the advice on the web which in general advocated measuring the distance between the seat bones then buying the narrowest saddle that ensured both seat bones were supported. If I’d followed that advice, I’d probably have bought a standard B17 – the best selling Brooks saddle.

My experience with other saddles had made me appreciate the buttock support of a wider saddle, so I chose a B68 and haven’t regretted it. Yet it seems I’m in a minority. Others in the group I ride with (we're fairly leisurely) have B17s. The B68 has been discontinued.

What have I missed by not choosing a B17? I’ve laced the nose of my B68 tightly, so I doubt that the saddle nose is significantly wider, if at all.

Sit bone (i.e., ischial tuberosity) width is an important consideration, but it is only a starting point, rather than the complete answer.  Your riding position also affects saddle width choice, with more upright postures being better supported by wider saddles.

Too wide only becomes a problem if you get chaffing or have problems getting behind the saddle for technical riding (e.g., cross-country mountain bike riding, without a dropper post - i.e., old school).

If the B68 is working for you then I wouldn't over think it.  Conversely, I can tell you from personal experience the discomfort of a Brooks saddle that is too narrow.  As the leather breaks in and you "sink" in a bit, you can start hitting the outer metal support frame with your sit bones.  Adding some more leather tension can help, but it doesn't completely solve the issue (I had to sell the saddle).

Why B17 has become the defacto standard is probably partly because it is a good saddle that breaks in quickly, and partly it has to do with the underground lore that evolved around it.  Sometimes its best not to meet our heros.


Maintenance lube for Aluminum Electra Townie My wife just bought me a used Electra Townie with aluminum frame and wheels. The previous owner claimed it had been serviced in the past year. Checking the bearings, I can tell it was a poor job of lubrication, probably done by the seller using who knows what for lube. What lube(s) are proper for the various bearings, etc on this bike?

Cup and cone bearings on a bicycle need 'preload' for them to work properly under load. This is because the balls are tiny spheres of metal that deform under your weight. Hence the bearings must be tightened up slightly beyond feeling smooth when unloaded. Due to quality of parts, i.e. not perfect, a pre-loaded bearing feels 'rough' and requires effort to spin it. There are proper ways of applying the correct pre-load, e.g. with the use of a torque meter, however, 'feel' is a good way to do it. To understand that 'feel', go into a bike shop and try to turn the spindles on the new wheels that are for sale. With rare exceptions all of them will feel rough - this is preload. Now see how your own spindles/axles feel when you turn them without load, chances are that they feel pretty much the same.

If you have rough bearings then you might think the grease is missing. Chances are that it is just the preload and not a grease problem at all. If you are going to dive in there anyway, do get a handle on the preload concept. As for your question on grease, a little grease goes a long way and you don't want it contaminated. The white lithium grease in a tube from your local bike shop will do fine. Yes you can buy posh coloured 'marine' grease but preload is what matters most with bearing setup.


Can cars legally drive in the bike lane down the street? Every day on my way to school there is a long street with a bike lane and two car lanes on each side. But when the street is jammed I have cars going really fast behind me and honking because I'm not going 45 miles an hour like their car is. Can they really do this? I mean it's the BIKE lane. It's one thing to be pulling out of a parking spot and crossing the bike lane but to be driving on it in general shouldn't be right. I live in Los Angeles, CA.

No. In California, a car can only drive in a bike lane 200 feet before making a turn from that side of the road or when entering or exiting the road.

California Vehicle Code 21209


Mismatched front and rear derailleurs ok for 3x7 setup? I'm thinking of fitting a Shimano Alivio rear derailleur and Shimano Tourney front derailleur to my 3*7 speed. Are they compatible with each other? Will I have to put same levels of derailleurs?

As long as the derailleurs match their shifters and their sprockets, you should be fine.

The front and rear derailleur are not attached to each other in any way. So it's no problem to mount different groups on one bike.

Its probably a good idea to at least stick to one manufacturer.


Are handlebar-mounted child seats illegal in Germany? I was told that handlebar-mounted child seats such as the Yepp Mini and the Bobike Mini are illegal in Germany.

People say a lot of things about what is and what isn't legal while biking in Germany. Can anyone find me some kind of authoritative documentation on this?

Front-mounted child seats are not illegal in Germany but face stronger restrictions than seats mounted in the back. Good sources and discussions (in German):

http://www.gesetze-im-internet.de/stvo_2013/__21.html (the law)
https://www.verkehrswacht-medien-service.de/kindersitze_fahrrad.html (good overview from a reliable source)

You need to consider in addition what kind of seats are adequate as covered by norms which provide the restrictions I alluded to:

http://www.kinder-fahrrad-sitz.de/stvo-ece-r44-din-en14344-praktischerklaert/
http://www.bike-eu.com/laws-regulations/artikel/2010/8/en-14344-european-standard-for-childs-seats-for-bicycles-1018845 (good explanation in English)

The EN 14344 norm is electronically available and covers every detail imaginable. It says in particular about front seats:

  8.3 Additional requirements for front seats Front seats shall have at least one attachment point to the cycle, which shall not be the
  handlebar or the extension of the handlebar stem.


Adjustment to road bike brakes for high grade downhill I have a road bike with a front brake that wears a lot of brake pad when I ride downhill every day. I lose 900ft in elevation on steep grades with lots of stop signs and traffic lights. On top of that, it rains a decent amount and the rim brakes are terrible in that weather. I don't trust them downhill in the rain. Sometimes I just walk.

I feather the brakes going downhill, because otherwise I'm too fast to stop quickly for an errant car.

It'd be nice to not constantly replace pads, and have powerful stopping. How can I make this constant downhill more pleasant?

Thanks.

Have a look at installing Cantilever brakes- larger pads so you can retain the same stopping power and increase life, at the expense of a few grams of weight.  Cantilever brakes will also help in the wet due large pad (more surface area). These are the preferred brakes for tandems and tourers - you may have trouble getting decent quality ones these days. As I understand, V brakes are not compatible with road bikes without adapters and are not always as successful as you would think.

Discs would be the ultimate wet weather improvement and provide the stopping power you want, but I would caution against hydraulics for such big downhills. They have been known overheat and boil the fluid - you get instant total failure when it happens. Apart form this, you need new forks and wheel (minimum of a hub), and probably new levers, so the cost may be prohibitive.


Twist shifter spacing between 6 & 7 My new cruiser bike has a twist shifter on the straight handlebar.  Why is there more space on the dial between the numbers 6 & 7?  The space between every other number is the same, except between the 6 & 7.  I'm a little OCD.

While most shifts rely in the very position of the shifter to precisely place the derailer aligned with the cog, the last gear relies in the limiter screw in the derailer itself. So, the last gear usualy "let the cable go" a bit more than needed, so that the limiter screw handles it.

Also, in the last gear, the derailer spring is almost unloaded, so that extra release of cable helps the last shift to happen.


What gears should I go for? I have a Trek road bike (although you might call it a hybrid since it has straight handlebars. I do about 3,000 miles per year on it for general health reasons (up to 30 miles at a time and averaging 13 mph) and I'm not into racing, cycling clubs etc (I'm coming up to 70). I've just replaced the front chain wheel with an identical version (Shimano Acera FC-M361 48-38-28T) and also the chain. I need to replace the rear chain wheel but before I do I thought I might ask for some advice.

The supplied rear chain wheel is a Shimano HG-51 8aw (i.e. 11-32T). Virtually all of my riding is on levelish ground and UK roads (as bumpy as hell!) with pretty shallow inclines - no off road riding. I find I rarely use the high and low front gears and virtually never use the bottom two rear gears. So what would be your advice on what gearing I should buy for the rear chain wheel replacement, and if you feel so inclined could you comment on the overall front and rear gearing - I feel its probably not optimal since I only seem to use 5 or so of the 24 gears!

If you aren't using many of the gears, then you should definitely go for something with a smaller range. The triple crank will give you plenty of range even without a wide range cassette. They sell 12-25 and 12-23 cassettes which may be closer to what you are looking for. I have an 8 speed cassette with a 52-42-30 crankset and I opted for the 12-23 cassette. I find there is plenty of range for climbing hills. The nice thing is that the gears are so much closer and I find that it's a lot easier to find the right gear in order to maintain an optimal cadence.


What are the safety concerns of a high vs a low mount trailer hitch? When you google for images of (canoe & bike) you find two basic solutions to towing a canoe with a bike.

A traditional axle mounted tralier is modified to have a tongue long enough to load/support the canoe/kayak on the trailer.
A seat post or carrier mounted pole connects to the front of the boat, the boat servers as the "trailer frame" with a canoe dolly (wheels that attach to the boat for moving by hand) for wheels.

Solution 2 offers the advantage of less material and more a portable trailering solution.  With this solution the bike and trailer easily fit in most canoes, so you have a fully amphibious combination.

Is there any significant safety considerations when towing with a bike from a higher or a lower tow connection on the bike?

The higher the hitch the easier it is for the trailer to push the bike sideways or lift the rear wheel of the bike under braking.

With the high hitch you can generally only do one of turning and braking at a time. So if there's a problem and you need to swerve and brake to avoid it, you will end up lying on the road with a canoe on top of you. And a bicycle. And a trailer. And they will all still be moving.

The solution is to disconnect the rear brake of the bicycle and use that lever to operate the the trailer brake, but few people do that because it's not trivial and in practice it's not really necessary. Most people find that the "tow my canoe" rig is big, heavy and unwieldly, so they only actually tow for short distances on flat ground. That makes riding slowly and carefully quite practical, and often they can choose quiet streets as well.

One other option is a three or four wheel trailer which you could do as a rear dolly and a front, pivoting pair of wheels. Handling will be better than a central dolly if you can work out how to attach the front solidly to the canoe. Or have a spine to the trailer.

This question is much more important for touring trailers and work trailers, where the distances covered are greater and there are fewer opportunities to avoid bad roads. That means the consequences of a crash are more severe as well. But at the point where you're building a trailer with brakes and suspension (because there are 4 wheels) it becomes worthwhile modifying the towing vehicle as well. Most people start down that path and end up with with a trike as the load vehicle or the towing vehicle, or a quad bike. It's much simpler to build and ride a single vehicle than a trailer.

Answers like this Burning Man Trailer one deal with the general details of heavily loaded trailers. It's also worth mentioning Richard Guy Briggs and his canoe carrying tricycle


Ultegra 6870 Di2 Synchro Shift I have an Ultegra 6870 Di2 groupset and I would like to use synchro shift.

In e-tube project, I select Customize, then Shift Mode Setting.

And I have an error message telling:

If SM-BRM1/SM-BRM2/SM-BTR2 is connected, shift mode will not function even if set.

What does it mean ? I can see that SM-BTR2 is the built-in battery, that I have on my bike.

Is it possible to use this function with 6870 ? If yes, how ?

Thank you

It is possible to upgrade your groupset to be Syncro-shift compatible. All you need is the new BT-DN110 battery. Once you have the new battery, you just need to update all the firmware, then set it to Syncro-shift with the e-tube software.


is there such as thing as a tapered-to-straight adapter for MTB headset? I am trying to assemble a bike for someone in my family.  There are a few challenges. The first is my limited experience, the second is her wish-list, which includes using a 27.5" MTB frameset she already has, a limited budget, and a preference to not use a MTB-style suspension fork but a lighter-weight rigid fork.
The headtube expects a  threadless tapered steerer, 1-1/2" to 1-1/8".  With the limited budget, that leaves only a few choices: low-end all-carbon or an alloy steerer with carbon-blades.  I have seen many low-end carbon forks on eBay, Amazon, and Alibaba, but the reviews are sprinkled with comments like "I had to take a dremel to the dropouts". So I would really prefer to get one with an alloy steerer from a "brand name" bike manufacturer. But they all seem to be straight 1-1/8" steerers, not tapered.
Is there such a thing as an adapter for a headset, whose bottom bearing assembly is a 1-1/2" to 1-1/8" adapter, something along the lines of this mockup:

Yes, many headsets made for it come with a crown race reducer. Cane Creek, FSA, Nukeproof and several other big names make them so that you can convert a tapered frame to accept a standard straight 1-1/8" fork. Just be sure to take note of what type of bearing/headset your frame uses whether it be external, zero stack or integrated.
You can also likely buy the crown race reducer separately to be used with your choice of headset. A google search for "reducer crown race" will net you the results you are looking for.


How to fend off a pack of feral dogs I really enjoy riding. However, today I had a, truly, terrifyng experience. I was chased by three feral dogs. I was able to out pace them, but it it really left rattled.
I understand that if one acts like prey, one gets treated like prey, but I am conviced thise dogs would have have ripped me to shreds.  Acting dominant and standing one's ground when dealing with a domesticated dog makes sense. Standing up to three feral dogs aounds like a death sentence. My question then, is what should I do if I'm confronted with this situation again?
Thank you.

You did exactly the right thing by getting out of there.

When a dog commits to an attack, they make a beeline in the last part of their approach straight at the target.  One technique is to cast and ride easy till the animal commits and accelerates, then pour on the power and accelerate forwards.  Animal will pass behind your rear wheel.  One or Two pedal strokes is all you'll have time for.

Risks are that you suffer a mechanical problem induced by the extra power.  If there's ever a moment you don't want your chain to break, its right then.

Three working as a pack would be extra terrifying.  Smart dogs will herd you, and these sound smart because they're still alive.

The dogs will most of the time go for feet and ankles, shins/thighs, because they're moving and are at the lowest height.  The might aim for a forearm or hand because of the wide stance of a MTB.   Adding barends might act as a shield/barrier for the hands.  Wearing stout leather boots with steel or composite toe caps will help if the dog gets that close.  Leather chaps would make riding hard and hot and uncomfortable.

As for defence, some suggestions with their downsides

Kicking - we all have feet and they're already on the bike with you.  But by kicking you're not powering the bike, which takes away from getting away.
Water balloons in a front basket for easy access - throwing at a small moving target is hard enough when still, from a rolling bike would be much harder.
Water balloons filled with fake skunk - same as above, but you don't want to break one on yourself.  However you might be able to smash these into the ground in front of the dog.
Water bottle squirt - surprisingly effective, if you have enough for a blast.  Again, one had off the bars, and aiming from a moving bike makes it hard.
Stick or baton - a few sticklike things might help, but if you're waving a stick then you have one hand off the bars already, decreasing your overall power.  Plus swinging is likely to change your center of mass and make you wobblier and unstable.    If the dog gets a mouthful of the stick/pump then they can pull you over, and more so if its a nightstick or a baton with a wrist lanyard.
Long lightweight stick - I'm not sure what plants are in your region, but here we have toitoi and flax bushes that produce 1.5-2 metre long lightweight poles.  I imagine bamboo is available worldwide that will fit the ticket.  Downside is carrying it on your bike.  Possibly as a flag pole, or as a load fastened to your top tube with light masking tape for quick removal.  Waving this in the general direction of the dog should help, they are moving fast and sound "whippy", and any contact is going to sting.
Pepper spray / mace - its not legal in my country but may be for you.  This may be enough to deter a dog but you'd have to get it into the dog's eyes and mouth.  Again needs a hand off the bars to apply, so best left till a dog's got its mouth on you before falling back to this defence.
Knives - too short to do anything useful, but again may be good after the dog has bitten down.  Go for the eyes.
Swords - pretty much all the bad stuff from above wrapped up, plus they're just as likely to cut you, and swords are expensive, kinda fragile, and heavy.
Firearms - this seems like a really bad idea IMO.  Again mostly illegal in my country.

As per water balloons, you will struggle to hit a small moving target
The location may not be safe to fire
Having the weapon may make you take on a fight that you should run away from.
A shotgun loaded with shot would be a better weapon, but even then not something to carry on a bike loaded.

If you do wound an animal to the point it can't get away but is still in pain, then "putting it out of its misery" may be a bad idea.  Smart animals can fake it to draw you close, and then lash out.   The dog's companions may use this as a distraction to attack you from the other side.  Your top priority is you.

Feral dogs are not good - long term you need to report this and hand the problem off to those who can legally do something about it.  There's a chance they're domesticated but reverted, and there may be a microchip or a collar ID to identify the proper owner.

And having submitted a report, you have prior proof that something has happened and therefore an excuse for carrying an offensive weapon.

The location is important too.  If you're in a national park there may be restrictions about where you can be and whether you can carry any offensive weapons.

Action camera footage can be beneficial to corroborate your story, and can assist in identifying the animals.  I always ride with a handlebar camera, but you might prefer a shoulder or helmet or wrist-mounted one so you can aim the lens.   If nothing else, it can be good for the youtube upvotes later.

Carry a basic first aid kit and consider adding enough medical supplies to clean and bandage a bite or two.  Better to carry and not need, than to need and not have.


Why does not the derailleur adjustment work the same way while riding? I suppose most of the people have noticed it. While adjusting both front and rear derailleurs, it will shift accordingly, when you have adjusted or are adjusting it, but when you test it by riding, the adjustment fail to perform the same way, Why does this happen?

How does the added weight affect the shifters?

Frame flex under the added weight affects the relative position of derailleurs and shifters, which is reflected in the cable length. Movements of the cable when changing gears are on the millimeter scale, so even lengthening of the cable by a fraction of a mm due to frame flex can have an effect.


Bike creaking when pedaling hard I bought my bike just 2 weeks ago and I always hear a creaking noise coming from the bottom bracket area. I can hear it only when I press hard on the right pedal on the downstroke. It sounds like a repeated metallic click, if that does make any sense. I brought it back to the shop and they tightened the crank axle, switched pedals and shortened the chain but the noise is still present.
Do you have any idea? Today I have tried other new bike of the same model and they don't make this noise.
EDIT: I am not a technician myself and I don't really know how to fix this issue but I really appreciate your answer. I bought my bike at a Decathlon store a few weeks ago and this week I went there 4 times and talked to 4 different technicians and none of them could even hear any noise. They already "fixed" the front derailleur more than once (Only limiter screw) and it is working perfectly, so I think that's not the issue. Another one suggested that the chainring bolts could be loose, but on my bike there is none (The ring on the Rockrider ST 520 are attached differently)
The noise I am hearing is present only when I push the right pedal, so there is nothing when I don't pedal or when I use the left one. What I hear is a fast repeated metallic click and I have no idea where it is coming from.

It could be a couple different things but new bike and metallic click plus only happening pushing hard on the right crank points to a very high likelihood of the chain rubbing against the front derailleur cage. This could be caused by either or a combination of:

The front derailleur cable has lost a little tension, which is common as bikes break in. Solve by tightening the barrel adjuster, which is easy to search for here.
The front shifter has trim stops you're not using properly. Again there are many questions about this here. This is more consistent with a shop getting it back and spending some time on it and the noise still persisting. Shop people will use the trim stops without thinking when they test ride a bike. Making sure trim usage is gone over with each customer is something that can fall between the cranks in sales and service interactions, and complicating matters is that some customers vibe like they don't want or need to be taken to school.
The front derailleur high limit screw might be too far in, although depending on the bike/crank/chainline/chainrings it could be how it is for a reason.


Tyre has a 'dip' in it after fitting to rim I'm riding with Continental Gatorskin/Hardshell tyres and they are quite tough to get on the rim.

After attaching the tyre and inflating I notice there is a dip in the tyre at the point where I had to lever it on to the rim.

I've tried deflating and re inflating the tube and trying to adjust the seating of the rim but the dip always seems to be there.

I notice the bump when riding and am a little concerned that at higher speed a little less traction might be an issue.

I'm hoping the tyre will eventually correct itself as it appears to be mishaped following the force required to get it on but might I have permanently damaged the tyre?

Does anyone have similar experiences or have any solutions? OR maybe this is normal when fitting very tight tyres?!

I used to get this a lot on my old 29er with Continental commuter tyres, large rim with tight tyre made for tough work getting the tyre on and off and often got similar flat-spots.

Check the max psi first but pumping up as hard as possible can ping the tyre beading back on to the rim wall, then deflate back down to your proffered pressure. If its still reluctant you can buy rim lube type stuff (could be a risky Google that, sorry) which is basically washing up liquid, so try that. Add a bit around the tyre wall / beading while its off rim and it will help ping on when you pressure up the tyre.

Track a pump will be your friend here.


Town bike intermittently harder to pedal I have a Dutch town bike with backpedal brakes (omafiets). I live in Amsterdam where it's flat and have checked the tires are fully inflated.

Originally the bike was very easy to pedal and often it still is. However, sometimes it feels about 20-50% harder to pedal. For example, flats feel like small upslopes and long upslopes feel intolerable. I'm trying to account for the slope, wind and my own tiredness. Occasionally it feels like I turn a corner and it's suddenly easier or harder. I'm often doing the same routes with different perceived difficulty.

My feeling is that something is sticking on the rear wheel. I have occasional perceived a small dragging sensation whilst pushing the bike with my hands (dismounted). My assumption is that the brake is slightly sticking. Two different bike shops have told me that this isn't possible. There is some slight side-to-side play in the wheel (about 1-2mm at a guess).

First bike shop said it would be the side-to-side play, second bike shop agreed so I had them fix it. They replaced the chain, pedal attachment, rear wheel and rear axle at significant cost relative to bike value. This did not help. Recently went back and they said the wheel is loose again, suggest tightening again. Of course, I'm doubting this is the problem.

I've read that cone adjustment should be done in this situation. However, my understanding is that tightening the wheel will actually make it harder to pedal - the adjustment is a trade-off between ease of rotation and stability of the wheel. Do I understand correctly?

Any other ideas on what could be causing this?

Are you sure you don't have a kick shift/kick back hub in the rear? I had this exact problem after I bought a new, used rear wheel for my town bike.

Seemingly at random it would be much harder to pedal, sometimes forcing me to hop off and walk up hills. At other times I'd be able to ride up the same hill! I thought I was going mad, and I too thought something was broken.
After a while I noticed a pattern, that it was changing in "difficulty" whenever i braked, ie. backpedaled. Now I love it, easy, hands-free shifting!

Sheldon Brown glossary page: http://www.sheldonbrown.com/gloss_i-k.html#kickback


I want to get rid of the front gears on my Scott Aspect 740 2016, what size sprocket would fit the stock cranks I would like to know the cheapest sprocket but good quality to buy to single speed my stock Shimano FC-M300 crank set to get rid of the gears and go "1-by" so its a single speed just on the front.

I think you meant your crank is a FC-MT300. That's a triple with 104/64mm BCD, symmetrical 4 bolt and 44/32/22 rings.

Any chainring that fits the 104mm BCD spider will work.

The cheapest option is to just keep the middle ring (you'll just need shorter chainring bolts if you take the outer ring off.)

Personally, as the 740 is only a 9 speed in the rear I would not ditch the large and small rings to make a 1x9, unless you live in a flat area or don't tackle hills and pretty much always ride on the middle ring anyway.

If you are thinking of swapping the rear derailleur, cassette and shifter as well, you will almost certainly be better off selling the 740 and buying a new bike that is designed as a 1x11 or 1x10.

Update:

There is currently FC-MT300 and FC-M3000 cranks in Shimano's Acera range (as afar as I can tell from searching in their line up docs). Either way they both have the same BCD and bolt pattern so the advice above is good.


Upgrade from 7-speed SunRace to 10 speed Deore: can I use the same wheel? I got a whole Shimano Deore groupset 3 x 10 and would like to upgrade my good old Trek bike. Do I need to change the whole rear wheel now? It has currently Sunrace Megadrive Lock Ring Type cassette or rather a freewheel.
And if I need a new wheel, what should I get so that it lasts?

You'll need to:

Maybe respace the rear dropouts, depending on the age of the frame. Modern wheels are wider than older wheels. For reference, 7 speed road is 126 mm, 7 speed mountain is 130 mm, 10 speed road is 130 mm and 10 speed mountain is 135 mm. Note that your frame needs to be steel for respacing to work -- if it isn't steel, you risk frame failure.
Get a new wheel -- something which has a Shimano-compatible 10/11 speed freehub (11 speed will also work with 10 speed). You could just buy the hub and rebuild your existing wheel with it, but you need a hub designed for the same number of spokes, likely all new spokes of the new correct lengths, and someone whose got experience doing it. Overall, in cost and reliability, getting a new wheel is probably a better bet.


Dual air forks negative positive chamber pressure equality Regarding solo air forks everything is clear. Once we bumped both chambers pressure is equal.
 But why for dual air forks air pressure doesn't try to get equal in both chambers? What's the point of second chamber if it has different pressure and doesn't try to equal it?

The negative air chamber provides resistance to the positive air chamber. It controls the speed air spring returns to its initial shape. The chambers are isolated so the air is unable to equalise.

The positive chamber provides resistance against compression, essentially how hard is the fork.

The third part of the suspension action is dampening, the negative air chamber controls the forks return and the damper stops if from oscillating and provides a smooth ride.

Rockshox explain dual air below quite well in suspension terms.


Needed training time or speed for each category of racer What type of training time or average speeds are needed to qualify for each category of racer? I realize that it can varry based on a hilly or flat route so lets assume a time trial of 40km that's relatively flat.

An example might be:

Cat 2 = 20+ hours a week of training and an average speed of 40km/hour on the time trial.

I'm not sure where to set my goals for my first racing season and figured a good place to start was to see where I fit already with training time and speed.

Speed is very difficult to use as a measure due to the fact that the measurements have to occur in an uncontrolled environment. Power, on the other hand is great because it's unaffected by the environment - it's a pure measure of what you're capable of doing at that moment on the bike.

A lot of power data has been collected by awesome folks like Andy Coggan who coaches racers of all different categories. One of the key measurements that folks use is W/kg in this analysis.

So a much better number for comparison would be 4.44 W/kg for functional threshold power (FTP) (average power over 1 hour) for the median Cat 2 racer. For the purposes of comparison, to win the Tour de France requires >6.4 W/kg FTP.

Here's a link to Andy's excellent article about power profiling where he talks not just about FTP, but what your power profiles should be for different durations (eg 5s, 1min, 5min).

Here's a direct link to a spreadsheet where he lays out what the numbers are for riders of different categories.

I highly recommend buying a copy of Andy and Hunter Allen's book: Training and Racing with a Power Meter, 2nd Ed:

http://www.amazon.com/Training-Racing-Power-Meter-Hunter/dp/1934030554/ref=sr_1_1?ie=UTF8&qid=1286482928&sr=8-1


What's in a good all purpose city commuting winter tire? How do I determine what factors lead to a good all purpose city commuting winter tire? Does the rim matter?

I'd like to not have to worry too much about looking out for and avoiding black ice, mainly because I'm not sure you can even do that reliably?

I'll be riding on roads and bike paths but if I encounter an unplowed section, I'd want to be able to get thru the snow without too much trouble.

I am interested in NYC so please factor that into your reply if possible, although a general answer would be great. FYI in NYC in January there's 8 inches of snow across 4 days, and 4 inches of rain across 10 days. Average temperature is 26F low, 38F high.

Your best bet for all around tire in the winter is going to be a cyclocross tire. They are made to race in grass, snow, on pavement, in sand, singletrack, and just about any way possible. They also have different types of treads for different conditions. You can't beat the Hutchinson Bulldogs, if you are looking for something more affordable, maybe the Maxxis Locust CX. CX tires offer low rolling resistance in the center of the tire, and have good grip on the sides. A less aggressive tread would be found on something like the Kenda Happy Medium. Give those a shot this winter and you shouldn't be disappointed.


How can I adapt my pedals to account for a difference in leg length? I have a leg length difference of as much as 1cm due to a non-biking accident.  Adding padding to my shoe doesn't help. A friend recommended that I get pedal stacks (and a longer bolt) to my SPD-style pedals (or any other clipless pedal) for my shorter leg. I know it will affect the rotation, but it's better than wobbling on my bike with uneven hips because of the 1cm difference. Any advice? And where can I buy a pedal stack or any other equipment, so that my leg muscles are as even as possible?

Be very careful about making leg length adjustments on your bike. There are several red flags about this. All of which you may be aware of or may not. 1st, a leg length difference is very difficult to diagnose, ecept with an experienced physio, or an X-Ray/MRI.

Most good physios will send you for an X-ray if they suspect a leg length difference is causing you an issue. 2nd, The body will naturally compensate for up to a 2cm leg length difference with pelvic tilt, and while that is less helpful on the bike, you don't automatically need to add stack height if you have a leg length difference.

And last, a 1cm difference in length does not mean a 1cm compensation, even if you do need to compensate. It is something that needs to be looked at professionally, and any compensation needs to be worked in slowly. Generally, adjustments in the 2mm range in one go are considered appropriate. More than that can(not always, but quite often) cause bigger issues than they solve.

Long story short, be careful what you do, go see a professional medical bike fitter, preferably a physio with extensive bike fitting experience, and follow their instructions. Oh, and be prepared to pay for the privilege, while realizing that it will take time to sort you out properly. There is no magic bullet fix here.

Look up the Boulder Center for Sports Medicine. They specialize in issues of exactly this type, and they designed most of the equipment to diagnose and correct them. Like the 3D bike fitting camera systems.


What is a sensible user service schedule for a professional work bike in non loaded applications such as food delivery? I am now a food delivery boy. I currently check brake and tyre pressure daily by riding. I wipe my chain and brake surfaces weekly. My weekly run is 400 km and 66 hours on road.

As a non mechanic what cleaning or user service schedule should I follow for safety and component longevity. I have already decided on 4 lbs services a year.

There is a similar question (but not the same question) here and here.

The short version is that regular upkeep -- chain replacement, cassette replacement, lubrication, brakes (modulo say rebleeding a hydraulic set), tires & tubes you should do at home as needed (and I've given some guidelines for the first two), and you should be familiar with basic adjustments for shifting and brakes. The shop should do repacking of the hubs (every 7500 - 10000 miles) and making sure the wheels are in good condition (this may be more often). Replace other things as they go. It'll likely be faster once you do it a time or two at home for the regular upkeep to keep doing it at home rather than taking it to a shop. You just need a few basic tools on hand (hex keys and a few special tools mentioned below).

I'd suggest investing in a chain checker (e.g. Park Tool CC-3.2) to check chain wear. Expect a chain to last, say, 1500 miles (this is conservative if you ride in clean conditions; use the checker to see if its worn or not). Replace when worn. You should be able to replace the chain yourself faster than a shop since all you have to do is pull the old one off, size a new one (e.g. by using the old one as a guide, its just pushing out a pin) and put a new one on (usually done with a quick link). Oil your chain and things like derailleur pivots and pulleys weekly.

You'll get a few chains per cassette/freewheel (maybe 2-3 of them). You should see this page on how to identify worn cassettes. Again, I'd suggest having a few cassettes/freewheels at home (depending on what your bike uses) and just changing them yourself. It's a quick job (less than 10 minutes) and just requires the appropriate freewheel/cassette tool, a big crescent wrench/vise and possibly a chain whip.

Chainrings generally last a long time -- I'd expect 15000+ miles if you don't dent them up on road use. Again, check for wear or dents periodically.

Brakes are important. If you're running rim brakes, make sure your rims have good braking surface (they last a very long time) and the pads are good and the brakes are adjusted. Again, wear depends on riding conditions and you can replace your rim brakes faster than taking it to a shop. You will also need to do adjustments if you have mechanical disc brakes (and replace pads periodically). Hydraulic brakes do need pads and occasional rebleeds/new fluid (if air gets into the system, for example; this should be on the order of year(s) though) but they do some amount of self adjustment.

Learn to adjust your shifters and brakes as necesssary.

At the mileage you're putting, I'd repack the hubs and have the wheels serviced in general (making sure they're true and what not) every 6-12 months (so lets say 9 months). I'd leave this to the shop.

Replace tires and tubes as needed (so when you get flats/slightly before they start giving you flats). You'll likely be going through a set of tires maybe every 8-12 months. Again, something you can do quickly at home.

Everything else, I'd say replace as they go (e.g. bottom bracket, saddle, pedals). If you want to be cautious, you could get a new set of cables yearly or something, but its not really necessary unless you live somewhere where the cables rust up and get ruined.

Finally, I'd suggest having a backup bike on hand if possible. Something a bit crappy, but will get the job done if your regular bike needs some upkeep (e.g. if for some reason theres a week turnaround on some repair, you have something to work with).


How to fix this unusual looking valve stem to put air in the tire? I'm wondering how do I fix this valve stem? I want to put air in the tire. But, i don't see the usual screw-on stem part. The other bicycle tire has such type of stem, so I am thinking this one is broken. How do I repair our replace it? Thanks for help,

update: thanks for the helpful info. i plan to get some more time on this during this week. this evening, i found a part with my pump kit that i was able to screw on. it didn't work with one of my pumps, but i have another pump i plan to try on it.

update: it was exciting to turn the top part from what i've learned from this thread and then be able to pump up this tire for my wife to have a working bike again. now, i know the usage of the other side of this pump attachment that i had never used before too. thanks for the help!

Your valve looks like a regular Presta aka 'french valve' to me. It's just a bit on the short side for your current rim.

I would recommend using a Presta valve extender, it could replace the small nut that is currently located on the valve stem assuming the valve hole in the rim wall isn't drilled out for a bigger size valve (the bottom of the valve extender will then push against the rim thus taking the function of the small nut that is currently installed). You could also just remove the small nut (once again assuming rim wasn't drilled for bigger size  valve stem) so you have a bit more room to install a pump. just make sure to depress the tire at the location of the valve as to prevent it from being pushed down when installing the pump.

Presta valve extender(example):

You could also try using a adapter to go from Presta to Dunlop or Presta to Shrader, if you remove the small (currently installed ) nut it looks like you should have enough thread sticking out on your current valve stem in order to install such an adapter.

Source

bonus info:
https://www.bicycling.com/repair/a20048610/the-difference-between-a-schrader-valve-and-a-presta/


Schwinn Vestige no longer lights up; why not? I have the Schwinn Vestige and a very long, bumpy, dirt/gravel driveway.

A few weeks ago, we rode downtown and the frame lit up amazing, as it should.
On the way home, it was not lit up. Hmm.

After a tiny amount of investigation, I found the cap and cover was missing (I mostly blame the driveway).
I ordered a new one (a mere 7 dollars) and installed it.  But alas, the frame still would not light up.

I clipped and stripped the wire from the LED's to the cap/cover thinking they may have been gunk-ified and re-installed the cap/cover.
Nothing.
I switched the red and black wire within the cap/cover.
Still nothing.

I tested the electrical output from the Shimano DH-3N30 Dynamo hub and all is good.
Still no lights. I pulled the generator/wires out from the frame to inspect for damage and, as expected, there was none.

I am at a total loss.

The local bike shop admitted I knew more about electricity then they did.
I cannot find any advice or schematic regarding how the lights light up nor can I figure out how to test the lights beyond the hub.

(Note that I have not probed the wires in the frame while spinning the wheel to check for connectivity.)

Daniel, I ended up going to the local Schwinn dealer and doing a warranty exchange on the lights. Schwinn supplied the whole new setup (as they had initially made it a non-repairable unit) and I installed it. I had to pull apart the entire headset and clip all the zip ties on the front fork. The whole process was time consuming, but not challenging. If the shop had done it, it would have cost me. The hardest part was treading the new cable through the hole in the frame and cutting it to the correct length


How can I mount a 25.4 mm seat-post on a frame that needs a 27.2 mm seat-post My bike has no rear suspension. So I thought of putting a suspension seat-post on it. Unfortunately the only suspension post available in my city is a 25.4 mm one. I have added some scrap metal to fix it for now. But it's still a little wobbly. What is the best way to do this ?

There are seatpost shims available for a few dollars. You should get them easily in your local shop or online.

I use an aluminum shim in one of my bikes with exactly the dimensions you need, it works flawlessly and looks very clean. I got it for about 3.50 € (5$).


What brand is this stem? Just wondering if anyone can identify the logo of the brand on this stem, thanks.

Well, a google image search of my image came up with Norco.


Building a Dirt Jump Bike - Spanish Bottom Bracket? I'm putting together a Deity Cryptkeeper and confused about which bottom bracket
to buy...

The specs say: spanish 73mm Bottom Bracket

Does this mean 73mm wide and 37mm diameter bearing?

I'd heard of English and French threaded BB shells. My first thought was that it is a mistake, but there is such a thing as 'Spanish' BBs. They are press fit direct into the frame and seem to be specific to BMX and dirt jump MTBs.

https://www.danscomp.com/tech-help/types-of-bottom-brackets/

http://www.moovebikeco.com/mtb/difference-between-euro-mid-and-spanish-bottom-brackets

There seems to be two crank spindle diameters. It would be a good idea to buy cranks and bottom bracket at the same time to make sure they are compatible.


What effect does changing the stem length have on my bikes handling I'm finding that when jumping my mountain bike seems to be very nose heavy no matter how far back my saddle is. What effect will moving to a shorter stem length have?

My bike, a Boardman FS-PRO came with a 100mm Richey stem. I think that moving to a shorter stem length will allow me, and my short arms, to sit further back on the bike and hopefully make steep dropoffs a bit easier to ride. I've heard that shorter stems make the steering quicker too. Will this make my bike unrideable?

A shorter stem does make your steering quicker, it also enables you to sit more upright and gives more leverage on the handlebar.

The longer stem gets you more forward and in a better position for climbing but I think it makes low speed steering awkward and is uncomfortable for long stretches on the bike.

I went from some ungodly long stem (100+mm) with a flat bar to a 50 mm stem with a small riser bar on my Rockhopper and I'm much happier riding it now.  Pulling up the front wheel is much easier (and of course this helps big time with hopping/jumping).  Also riding off larger drops is easier since you it is easier to hang over the rear of the bike as well.

If you're primarily dirt jumping and free riding, I'd say go with the short stem.   Honestly the only scenario where I would consider going back to the long stem is if I decided to start doing a lot of XC riding involving lots of climbs (NO THANKS!).


Brake pads constantly touching the rotor because piston is not moving back I recently replaced the brake pads on my hydraulic disc brake. The brakes are a Tektro Draco 2. Now the new pads are constantly touching the rotor.

This is how it looks like with caliper unmounted. Notice the left piston is constantly sticking out:

I tried spreading the pistons with a spacer. I left it in there for 3 hours

But still, the left piston comes out again. I'm thinking about buying a service kit to bleed the system. Will that help?

I left the spacer in overnight. The Piston now goes all the way back. Guess I was just too impatient :)


Restoring BSA bike - replacing rear wheel and freewheel I'm trying to restore an old BSA bike. I want to salvage a Sebco freewheel from a very messed up wheel.

I want to know what do I need to remove it. Am a newbie home mechanic so I know nothing.
Since I have to replace the rear wheel, can I swap the single speed freewheel for a 5/6 speed freewheel. It just makes the bike a little more ridable for my sister.

https://photos.app.goo.gl/rLsmWk7X0t6Y54s32

https://photos.app.goo.gl/6OEXYSrs8BnFOkmF3

I was planning to replace the rear with the one in the link. Is this possible?

http://www.ebay.co.uk/itm/like/352025038637?chn=ps&dispItem=1&adgroupid=46343423714&rlsatarget=pla-327268230718&abcId=1128926&adtype=pla&merchantid=7285664&poi=&googleloc=1006912&device=c&campaignid=856845593&crdt=0

Getting the freewheel off:

You need a special tool that fits in the notches in the threaded part of the freewheel, which you may or may not be able to find. In any case, the freewheel is likely worn and it will definitely need servicing so you are not going to want to re-use it. Just get a new one.

A note on wheels:

Older bikes often had rim diameters that are not the same as commonly available modern wheels, you'll need to be careful about rim sizes. A slightly different size may fit the frame but you have to make sure the brakes can be adjusted to reach the rims.

Beware that the 'size' commonly given for a wheel is not the actual rim diameter. See this Sheldon Brown page for details: https://www.sheldonbrown.com/rim-sizing.html

You'll also want to be similarly careful about the frame dropout spacing and axle length. See this SB page: https://www.sheldonbrown.com/frame-spacing.html.

On retro-fitting a derailleur system:

Almost certainly not possible as your frame has too-narrow dropout spacing to take a wheel with a multi sprocket freewheel. Also, it will be expensive and a huge pain to do. better to just buy a cheap used geared bike.

On retro fitting an internally geared hub:

Technical possibility. I believe Shimano and Sturmey Archer make internally geared hubs for a range of frame dropout widths. You'll obviously have to consider whether the cost is worth it for you.


Visual inspection of wheel hub I need to build a new bicycle (others are gone, stolen :( ). Good thing is, I have two spare wheels of decent quality in my basement.

These old wheels took quite a beating though, when I was younger. No truing, many jumps and crazy stuff. I even remember my front wheel popping out of the fork during a jump. The landing was bad for the wheel, trust me. The quick release skewers are bent, and probably scratched (or worse) the inside of the hub when I removed them.

Now I'd like to reuse these good old wheels (both front and rear). But before that, I want to make sure they're still safe to use. The wheels are old anyway, so I figured I'd take the hubs apart to lubricate them.

So, three questions:

can I take my (front + rear) hubs apart while it is still attached to the spokes?
is it good enough to visually inspect the hub axle, and decide whether it's safe to use based on that?
any other safety concern?

can I take my (front + rear) hubs apart while it is still attached to the spokes?

Yes, of course you can.

  is it good enough to visually inspect the hub axle, and decide whether it's safe to use based on that?

Well, there's not much else you can do, so yeah, I'd call it good enough. If there's any doubt, I'd just replace the axles.

  any other safety concern?

Cracks in the hub body, especially at the spoke holes.
Cracks in the rim.
Rim so badly out of true that it can't be fixed. Not really a safety thing, but it could make the wheels useless.


Help me ID this bike I purchased an old bike and I can't quite find out which brand and model it is. I know it has an Aluminium Kinesis frame , which is pretty light . The bike weights about 9,5kg with the bottle holders and the bike saddle bag on.

It has the Shimano FC-1056 crankset, Shimano BR-1055 brakes , Shimano 5500 front derailleur,hubs and Shimano Ultegra RD-6500(I broke it , got a new model) with Shimano ST-6500 brifters.

The headset is Apollo , stem UNO Kalloy , handlebar Modolo 6QEven. The frame looks to be in a perfect shape , no bents , no scratches.The rims are Mavic CXP 30. The bottom bracket serial is : K(or H)25200227.

Here's the album : http://imgur.com/a/91iba

P.S After all the help I got from BikeWrench (which I appreciate), I decided to try my luck and search for the bike model. After 2 days of seaching, I didn't find anything. P.S.S Sorry for my english. Not my native language.

Try making contact with either of these.  Their logo is almost identical to the decal on your bike.

http://www.kinesis.com.tw/?lang=2&TTo=en
http://www.kinesisbikes.co.uk/

Possibly this one, but less likely:

http://cannibale-bikes.e-monsite.com/


Can my cantilever brake pads not being centered lead to a problem? I just watched a Park tool video on cantilever brake adjustment.
The mechanic pointed to a small screw and said it was to center the brake pads but did not say why. Obviously two forces that oppose each other should be applied evenly. My question is,can uneven application of the brake pads lead to a problem other than inefficient braking.

On rim brake calipers the cable pulls the two sides towards each other to 'pinch' the rim. If one pad contacts the rim first it will not exert any significant force until the opposite pad contacts the rim.

Centering the calipers allows the distance between the pads and rim to be minimized, thereby reducing the distance the lever has to be moved before braking force starts to be exerted.


How to check for aged/deteriorated weel rims Whenever I plan repairs on an old bike I go to check the local bike shops for some information, prices, ... One of the things I noticed in the past years is that more and more they try to replace as many parts as possible. For most of those parts I can determine myself if they need replacement. But I have difficulties determining this for rims.

Is there an easy and/or quick way to determine the state of the rim without to many special tools (or expensive tools)? What are the minimal tools you need to do this?

The wheel should run true

radially (up/down)
axially (sideways)
and should not be twisted (as each spoke applies force at its eyelet, a weakened rim might twist, and this twist might not be noticed whilst truing out axial deflections).

The form of the bead interface should be consistent, no dents in any direction (unless the rim is for tubular "stick-on" tyres, in which case it would not have a bead seat).

If the rim has a braking surface, it may have featured wear indicators. These would be either square-edged grooves or cylindrical indents.

If the braking surface has become concave, the rim wall connecting the bead interface to the well of the rim (where the spokes end) might be dangerously thin. A failure here would be characterised by a sudden separation of a metallic ribbon as the bead interface succumbs to the force applied by the tyre pressure, and the tube would expand through this new opening until the tension in the rubber exceeds its strength or the sharp edges of the broken metal pierce the tube.

The metal surrounding each eyelet should not be deformed. A wheel that has been repeatedly trued may have excessive tension on some of its spokes. A wheel with insufficient tension would not distribute loads appropriately as it rolls, causing spoke tension to fall an rise. Changes in tension cause deformation in the rim and spoke. Metals have a finite capacity for load cycles, ending with a fatigue failure.

The rim may tear at an eyelet, allowing the nipple to pull through and causing a sudden change in the tension distribution of the wheel, which may deflect enough to cause contact with the brake or frame. A complete localised loss of tension may also result in a load exceeding the capacity of an unsupported rim section, resulting in a catastrophic failure of the wheel and sudden changes to the trajectory of the rider.


Bottom bracket making noise, should it be fixed now or can I wait until regular maintenance? My bike has been ridden 4 months / 2000 miles and is no longer completely quiet.

About a month ago I noticed a whispering noise like a wire brush sliding across a cymbal. It happens on the power-down-stroke, in any/every gear, so I think it must be the 'bottom bracket' or something close to that. A noise (creaking) is now happening on both strokes (both feet).

No one mentioned bearings when I asked How much does bike price correspond with maintenance needs?

A co-worker said it needs fixing when the pedals are 'loose' (which they aren't).

Can it wait another 2 months / 1000 miles or so until its first regularly-scheduled twice-annual in-LBS service?

Or is it a case of "an ounce of prevention is worth a pound of cure," and I should ask someone to maintain it a.s.a.p. before it gets (irreparably) worse?

Do they even need maintenance, or are they just replaced sometimes?

There are several possible causes of noises you can get from your bottom bracket.

Bad bottom-bracket bearings
Bad pedal bearings
Loose crank arms
Loose bottom-bracket cartridge
Loose chainrings

Of these the loose crank arm (which may be silent or may be accompanied by a creak on each stroke) is probably the one needing the most immediate attention, since riding even 10 miles with a loose crank arm is enough to destroy the crank arm and crank shaft.  So you should either check that the crank arms are tight yourself (by torquing the fixing bolts appropriately) or have a bike shop do it.

After that, I've experienced most of the above, but probably the bad (or simply dirty) pedal bearings more than anything else.  Pedal bearings seem to pick up dirt faster than any other bearing on the bike (especially when offroad or riding on packed gravel), and unless they are well sealed may need regular disassembly and regreasing.  And I've had new, sealed pedals develop noises in as little as 200 miles (though the set I have now have been fine for probably 8000 miles, knock wood).

I did have the bottom bracket cartridge on my current bike start making noise after about 5000 miles (more of an occasional click than grinding).  On disassembly the (Shimano) cartridge was found to be badly rusted (even though the bike is only left out in the rain when commuting).  Replaced it with a SS Phil Woods unit.

The BB bearings went out on my old Nishiki after a few thousand miles, and on inspection it appeared that the cups had been poorly machined to begin with.  (This was maybe 18 years ago.)  Replaced the loose bearings with a Performance cartridge.

A bike with only 2000 miles on it should not need any bearing service, unless it's been seriously exposed to bad weather or other severe conditions.  But note that 2000 miles is about the expected life of a chain, and yours is probably due for replacement.


front gear shifters not working I made some adjustments to the front derailer on my road bike as when I was in the big front gear and smallest low gear the chain was rubbing on the front derailer outer edge.

I followed guides on how to do this, have changed the position of my front derailer, adjusted the derailer screws and put everything back together. But I am unable to get the shifters for the front gears to have any affect on the derailer. The cable is reattached and as tight as I can get it, and I have tightened the barrel adjuster as much as I can yet I get no tension in the shifter at all. the cable itself feels tense and when I use my hand there is no issue with derailer movement.

What can I do to regain gear control?

From the question I'll assume the shifter lever moves, but it does not pull the cable.

My guess is that the shifter end of the cable is not seated in the shifter properly, or has become hung up somewhere. This may have happened when the cable was loose while not connected to the derailleur.

Unclamp the cable from the derailleur
Find where the cable is seated in the shifter, you'll have to pull back the rubber hood covers to find this, check the boss on the end of the cable is actually seated in the shifter properly
Check the cable run: verify the cable runs the housing unimpeded, especially at the shifter end, make sure housings are fitted in bosses properly, look for snags in the cable
To test, hold the cable where it run exposed or at the derailleur and put a little tension on it, actuate the shift levers and feel for the cable moving