Is it legal for cyclists to use amber bike flashers for visibility (in BC, Canada)? Amber bike lights can improve daytime visibility. This makes sense because white light looks similar to sunlight and amber light stands out more clearly. Being seen sooner means that drivers have more time to react. Possible situations that benefit from improved visibility include users changing lanes, traffic circles, users turning, drivers opening their doors, users waiting at cross streets, and oncoming users passing. Also, amber may be easier on our eyes which can improve safety even more.

The question is whether it's legal to use them in BC? Does the BC Motor Vehicle Act say anything about it?

If it's not legal, then a possible alternative might be to avoid strobe patterns.

Dinotte sells amber bike headlights.
http://www.dinottelighting.com/LED_bike_lights/dinotte-daytime-amber-aa-headlight.htm

Video of a Dinotte amber light being used:

From local bike stores, it's getting more common for bike lights to have amber for sides.
https://www.mec.ca/en/product/5053-077/Bottle-Blinky-Sidelight
https://www.mec.ca/en/product/5055-194/Urban-900-Light

Here's are some custom made ones.

https://www.instructables.com/id/High-Powered-Yellow-Bike-Light-FrontSide-Combo/

BC Canada

https://engineering.ok.ubc.ca/__shared/assets/Bike_Sense-Nov0552189.pdf
says

  After dark, all cyclists are required by law to have a front white
  headlight visible for a minimum of 150 metres, a rear red light
  which should be visible for a minimum of 100 metres, and a
  rear red reflector visible for 100 metres when directly illuminated
  by a car headlight. Many rear red bicycle lights sold currently
  are also designed to function as a reflector and are legally
  acceptable. Flashing red rear lights are also acceptable. Lights
  and reflective devices come in a wide range of shapes, sizes,
  colours, and costs and should be mounted directly on the bicycle.

There's an implication at the end that body-mounted lights are bad, but whether that's law or a suggestion is not stated.

There's no stated restriction on colour.  The only mention of flashing relates to the rear light which is permitted.

http://www.icbc.com/road-safety/sharing/Pages/cycling-safety.aspx says

  Your bicycle must be equipped with a white headlight visible at 150 metres and a rear red light/reflector visible at 100 metres

https://www.thenoteup.com/single-post/2017/02/28/Helmets-and-bike-lights-BCs-cycling-laws reiterates the same.  Neither make mention of flashing fronts.

ANSWER Ambiguous - but you're unlikely to get in trouble for the colour of your lights.  Flashing seems to be conspicuously absent for anything but rear lights.


Do cyclists make safer drivers? Is there any research that suggests cyclists are safer drivers than drivers who don't cycle? Is there evidence to suggest the opposite?

Please remember this is not a discussion. Please include references to credible research in your answer.

I found a report from the Institute of Advanced Motoring on Cycling Motorists. The vast majority of motorists believe that cyclists do make safer drivers.

Even those motorists who don't cycle believe that cyclists are safer drivers.


Jitter/Sticks on Coaster Brake Hub Wheel I am having a major problem trying to get my Coaster Brake Hub reassembled properly...

I've tried with 2 separate wheels, different components and all.

Here's a video of the problem:

I am using the exact same system as this guy in the video:

Do you have any idea of what is STICKING, causing it to jitter like that?

I'm tried reassembling it 4 times now on 2 separate wheels with duplicate components.

I've tried different tensions - it's as if the insides might be a bit worn out or...?

Anyone have any experience on this?

I don't know if this model/brand of coaster brake has one, but what I have seen this problem with Bendix coaster brakes and the culprit is a worn retainer spring or a worn driving clutch. Read this article from Sheldon Brown: https://sheldonbrown.com/coaster-brakes.html


Bikepacking With A Carbon Bike I'm looking at doing a decently long bikepacking trip mostly on road. I currently have a carbon framed orbea avant endurance bike. I'd like to do the ride without necessarily buying a new bikepacking bike. I was thinking that a seat post bag, frame bag, top tube bag, and maybe a backpack to ride with and putting 28 or 30 mm tires on. Does this seem reasonable as a setup? I've done century rides on this bike before and it's comfortable enough. What are the drawbacks of a carbon endurance bike vs. a more bikepacking focused steel or aluminum bike? I know if the carbon cracks I'll be SOL.

Yes it's reasonable, assuming your bike is in good condition when you leave home.  Frame failures end most trips regardless of frame material (the bravado of "A village mechanic welded my frame" rarely comes to pass).  Lots of people are bikepacking on carbon bikes--carbon frames have even accelerated the bikepacking trend because they typically lack rack mounting eyelets.


9-speed Sora w/discs to 11-speed 105 - What Sora bits can I keep? I'm planning to upgrade from 9 to 11 speed, Sora 3500 to 105 5800.

I'd like to keep my existing mechanical disc brakes, which I believe I can, but please correct me if wrong.

Also, if I bought the full 105 groupset with rim brakes (cheaper than set with hydraulics) and just sold the brakes, would everything else still work on my bike with disc brakes?

Lastly, other than brakes, what can I get away with not replacing.  Bottom bracket, shifters, crankset, FD?  Thanks.

You'll need:

A Shimano 10 speed mountain/ 11 speed road rear derailleur
A Shimano 11 speed road front derailleur (since they apparently work differently than normal ones)
Shimano 105 shifters (Front and rear; given the cost of a new FD and the resale plan, you don't really want to reuse the old one + the old front shifter)
11 speed chain
A freehub on your rear wheel which can take a 11 speed cassette
A 11 speed cassette

The brakes will work fine. If you do replace the crankset, you'll likely need to replace the bottom bracket as well. The crankset should work, but it might not be optimal -- on SRAM, the chainrings have been spaced slightly wider apart on 11 speed and the chainrings are likely a bit thinner than 9 speed, which may be the case with Shimano as well.


How to prepare oneself for riding in the snow? I live in western Germany and have started to ride to work almost everyday. It is great at the moment as it is summer (not as dry as I hoped for, but that is another story). So the only thing I have to really deal with is rain and, sometimes, cooler weather.

In the winter, it sometimes snow, and will definitely have ice on the roads and trails that I ride. What can I do to prepare my bike and my clothing for riding in the winter time? I am even considering getting a new bike as my current bike is quite worn and needs to be updated.

I know that this is quite broad, but I hope to create a list of things (or community wiki) to do for preparing for the winter time.

Studded tires are a must on ice. They are expensive, but well worth it! A couple of points to consider that have not been mentioned:

Footwear: Winter specific riding shoes or boots. For mountain biking and cross, I ride with Lake boots. On the road, I use an older pair of road shoes that have been stretched to accommodate thick wool socks and neoprene shoe covers.

Head-wear: I typically ride with a helmet cover all winter. I also bring along a couple different varieties of skull caps on ride ranging in thickness, ear/face coverage etc... yes to balaclavas!!!

Depth of snow: whether you are running studs or not, my experience is that if the snow is deeper than 4-5 inches, it is not ride-able. In this case, it is best to wait until either the cross country skiers, hikers or plows(in the case of roads) have cleared or packed down the snow.

Body Temperature: Many cyclists new to riding in colder weather tend to over dress. The trick that works for me is twofold, first absolutely dress in layers and second I want to be cold, not freezing, but cold as I go outside and get my bike ready or at the very start of the ride. If I am warm at that point, I will be sweat soaked in the matter of minutes and wetness is something you want avoid!

Fender: Clearly, if the snow is dry, it is not necessary, but my experience is it is better to have one as a precaution than go without!

Heat Packs: At extreme temperatures, I have successfully used heat packs in the tips of my shoes and palms of my gloves. I am not a huge fan of use in the palms, I very rarely and if i do it is usually just a temporary fix.

Use of Car Heater: If I am driving to the ride, I preheat my shoes and as much clothing as possible using my car heater on the way to the ride.

If you get yourself set up with studs, I would highly recommend finding a frozen lake or pond to ride on! The experience is phenomenal! If you can time the lake ride with 1-2 inches of fresh snow it will be that much better!

I ride road, mountain and cross year round outside. Hope this helps!


electronic security tags Are electronic security tags (e.g. Immobitag, Datatag) a good idea? Are the stickers likely to deter theft and does the electronic tag increase the chances of recovery in the event of theft?

I suppose 'every bit helps' but, in a nutshell, 'no'.

Having reported my bike stolen and having handed in a lost/stolen bike (so I could recover it under finders/keepers rules) I am familiar with the backwardness of the whole Police process of dealing with stolen bicycles. Last time I went through the hoops the concept of 'mountain bike' was new fangled - you could specify rod or caliper brakes but not cantilevers, never mind disc or 'v'. Frankly it is a miracle they ever repatriate bikes due to visual identification. Given this one would expect that the 'Datatag' would be exactly what everyone apart from the thief needs...

I also know that 'Datatags' are definitely not what you might call a hot seller in bicycle shops - they might be in the motorbike world but bikers only put them in because they have to be insured. If they were that good then people would be queuing up for them, as it is they just collect dust in bike shops that actually stock them. This means that they are not in common circulation. This affects the likelihood that the Police will check for them as well as their deterrent effect to thieves.

The likelihood of your tagged bike being found by the police is going to be slim, only if it gets handed in are you likely to benefit from the Datatag and that is assuming the Police have one of those scanners anyway. I have not heard of these things working - there is a complete absence of anecdotal evidence on the internets too. I think that 'Datatag' stickers are a bit like car alarms in that nobody takes them seriously except for insurance companies. This is no criticism of 'Datatag', the product they make and the goal of the product, it is just that there is a big difference between the marketing theory and the practice.

That said, I do have faith in the new Bike Register scheme and have my bike tagged by the Police. Most Police do have days in the town centre where they mark bikes up for free.

Given that the scheme is free and endorsed by them you have to wonder why bother with any other scheme, particularly if there is practically no evidence of it having ever worked.

http://www.bikeregister.com/

You get stickers with Bike Register and you put all your details with them, an improvement on postcoding.


Best places to put protective clear stickers I want to protect the new paint of my bicycle, so I'm thinking of putting some transparent stickers to the most prone to scratch areas of the frame.
But what are the most prone to scratch areas?

Here are a few places you may want to consider

Right chain stay where the chain knocks against it.
Bottom of the down tube where rocks might get flung from your tires.
Around the headtube, check if there's any place where the gear and brake cables contact the frame when turning the bars. Rubbing cable mat seem insignificant but can easily wear away paint with enough time.


How can I tell the difference between a J.I.S. and ISO square taper bottom bracket? I have a square taper bottom bracket. How can I tell whether it is a J.I.S. or ISO taper with a minimum amount of disassembly?

FWIW, it's a Ritchey from 2004. However, it would be nice to get answers that apply to other brands as well.

The width across the narrowest part of the flats (end of spindle):

JIS = 12.65mm

ISO = 12.33mm

Use calipers.


How do I remove a pedal from a crank with a crossed thread? I've part stripped, and ultimately crossed the thread on my crank and can't remove my pedal now.  This was done whilst riding and then trying to remove the pedal from the damaged crank.  I figure the crank is toast but I want to remove the pedal without damaging it.  Does anyone have any simple way to do that?  My best theory at the moment is to use a hack saw to cut through and then either use a chisel to widen the gap or to then make another cut to free the pedal completely.

The main reason I haven't just done that is that I'm worried about damaging the pedals threads.  I want to continue using this set of pedals.

Here is a picture of the pedal, it wobbles about in the crank but I haven't managed to pull it out.  I tried pulling the pedal while someone undid the pedal but the thread appears to be too screwed up.

I'm guessing the pedal is toast too, but if I wanted to try to save it (and it refused to come out with simply a wrench and a hammer -- counter-clockwise on the right, clockwise on the left) I'd get out my trusty Dremel and make a slot or two in the crank, parallel to the pedal shaft.  (It won't hurt if you nick the pedal threads a little bit.)  Then drive a small cold chisel into the slots to spread them a bit.

(I do wonder how you managed to cross-thread the pedal and then ride on it.)


Mountain bike rear wheel tilts after remounting Backstory: Total newbie regarding repairing cycles and the proper cycling terminology, so please take that into account.

Actual story:

I had a fall and the rear wheel started touching the brakes (non-disc), so I took it out aiming to remount it and as a final result I broke the quick release.

After a long walk home, went and bought a new quick release (the wheel has some nuts to some effect I'm not 100% sure about). I installed it according to this video (and also followed the "tight enough to leave a mark on the hand, but no tighter" rule I read about somewhere), seemingly aligned (in the middle between the frame). Now, I see two things:

The wheel tilts sideways about 1/4" or a bit more, it's not fixed.
When under load the wheel ends up either touching the brakes or directly the frame.

Thus I think that I'm either misinstalling the wheel, or that after the fall something else got broken or damaged.

The actual question is, how to find the actual problem (misinstalling the wheel or something else, or both) and its solution?

EDIT: Here's a video of how the wheel tilts, and another video of a possible culprit (damaged spoke). Could that damage explain the amount of tilting?

It could be some spokes or the rim got damaged. You should try touching them to see if any is broken. If they are loose you should tighten them to align the rim. If you can't do it yourself a bike shop will do it for you easily. Broken spokes can be changed.


What's the difference between Shimano HG and SRAM XD free hubs? I know that the Shimano free hub is pretty common. I think it's called HyperGlide (HG). But now I heard that SRAM has a free hub called XD. What is this? What is the difference? When do I need it? Can I replace a HG free hub with a XD free hub?
I also heard that Shimano introduced a free hub called Micro Spline. But this is only for 12-speed cassettes, right?
Last but not least, I heard of a free hub by SRAM called XDR. Is this a "better" and more "expensive" version of XD?
All in all it's very confusing. Sometime I see that some hub is compatible with this or that but I cannot find detailed information about the differences and the compatibilities between them.
In general, how do I know which of them fits on my hub? What are the benefits of each of them? Are they compatible?

SRAM's XD and XDR drivers (their term) don't have splines, unlike Shimano and Campagnolo freehub bodies. Instead, their cassettes screw onto the threaded section of the driver as shown in the image below.

They did this to

Address the shortcomings of Shimano's Hyperglide (HG) freehub, namely that the small splines got chewed up
Because they wanted to implement cassettes with 10t small cogs, so they needed a shorter freehub body anyway. The diameter of those cogs is smaller than the diameter of typical freehubs, so the XD(R) drivers are shorter than the HG freehubs.
Because Shimano was not going in that direction at the time of SRAM's implementation of this standard (2015 or so)
Finally, to be different

SRAM explains that XDR is just the road version of XD. XDR bodies are 1.85mm longer than XD. I believe that MTB cassettes can mount to an XDR body with an additional spacer; Shimano actually does a similar thing because on the MTB cassettes, the biggest cog is cantilevered over the freehub body.
In general, most hubs will come with the option for Hyperglide (HG) or XD(R) bodies, and possibly Microspline, regular Campagnolo, or Campagnolo N3W freehub bodies. Yes, there are a lot of standards, and yes, Campy has two of them as well (N3W allows the cassettes associated with their 1x13 gravel groupset to mount). In any case, you would be able to change out the freehub if you buy a new one, provided you actually want to change your groupset. (If so, note that 11s road cassettes are interchangeable, and 12s road cassettes should be also.)
Basically, you will want the freehub/driver type that matches the groupset you are getting or that you have. If you have Shimano road, you want HG, keeping in mind that their road groups are expected to transition to microspline starting this year. If you have Shimano MTB, you want microspline. If you have SRAM, you want XD or XDR. On the off chance that you switch to Campagnolo, you'd probably want to get the N3W body if one is available; there's an adapter that allows you to run regular 9, 10, 11, or 12s Campy cassettes on the N3W hub.


How to reinstall a tension screw of a V - brake that been fully unscrewed I just bought a new showgun mountain bike and I was loosening the tension screw and it came completely out and I'm having a problem putting it back in

Yeah loosen the brakes ,hold them with your hands such that the brakes just does not touch the rim of the wheel then tighten it .

If you find it a bit loose the adjust the secondary screw for more accuracy .


How often should I change brake cables and housing? Seems like every year towards the end of cyclocross racing my brake cables start to get 'sticky'. The STI shifter is fine for changing gears, but when pulling on brakes it feels like I'm breaking loose something stuck before the pads actually touch the rims. I think water/mud/grime is somehow working into the housing and adding friction.

I have replaced the cables and housing about this time every year. Is this too often? Should I be doing some better (more) maintenance? - I rinse and wipe bike clean after every race and practice, but not really anything special for brake cable/housing.

side question: Should I change shifting cables and handlebar tape at the same time (since I'll have the wrap half way off)?

I encourage replacing once there is a noticeable decline in performance (usually that means that they get "sticky").

Depending on the type of elements you go through, you might get back most of the perf by pulling the cable most of the way out, adding a drop of thin oil, then sliding the cable back through all the housing. Repeat a couple of times wiping cable each time. This will often clear the bits of gunk that are making it sticky.

Changing shift cables/tape at same time:
Tape...absolutely, it's cheap and I always feel like I've treated my bike nice when it's sporting new wrap.

Shift cables...if they are in good shape and the drive train is clicking along nicely, I tend not to mess with it. If they are getting sluggish like the breaks, then I'd go ahead. Keep in mind on the shift cables that they will stretch a bit so you will need to tighten the cable and possibly do a slight retune of the drive train a bit after a few days.


Are there measurements of road bike tire friction coefficients? I am trying to learn about the maxium lean angle of a road bike. I'm looking for measurements and comparisons.

There absolutely do exist tables of tire friction coefficients; see here for an example -- but friction coefficients may not be exactly what you're looking for.

I don't know of any specific tables that measure lean angle and here's why:  we do know some of the factors that affect rolling resistance. They include tire construction materials, type (tubeless, tubular, or clincher), tire width, tire pressure, road temperature, road surface, inner tube material (butyl or latex), rider weight, and, because of interactions between road surface and these other variables, sometimes speed. Because these affect rolling resistance, they will also affect maximum lean angle.

Many of the tables that show rolling resistance coefficients were measured under controlled conditions in a lab, using rollers of known diameter and known surface (smooth or bumpy) driven at a known speed. However, some tables are calculated from field tests on real roads. Although the roller test values and field test values may differ, comparisons made by those who have done both show that the relative ranking of tires is almost always preserved (that is, if tire A has lower resistance than tire B on rollers, it almost always has lower resistance than tire B on the road).

Measuring rolling resistance is possible for interested riders, but it's not easy. It's akin to measuring aerodynamic resistance -- in fact, if one is doing field tests outdoors on real road surfaces, the common methods of measuring aerodynamic drag also provide a measurement of rolling resistance drag. The easiest method for outdoor field tests uses an accurate and precise power meter available but it is also possible to do without a power meter (though at greater effort and time). That said, if you have a power meter and a set of rollers with a front wheel stand, you can measure tire rolling resistance yourself, without the complication of the aerodynamic drag component.


E-Bikes and Kid Trailers? Anybody know if you can attach a kid trailer (example: https://www.buybuybaby.com/store/product/burley-bee-bike-trailer-in-yellow/1061738171?skuId=61738171) to an EBike? I have a huge hill to go up to get home and would like some help. I'm worried I might break the bike with the excess weight or it won't be able to accommodate the trailer.

Thoughts?

Anybody done this?

The details depend on the exact trailer and, more importantly, on the bike.

There are lots of trailer couplers that simply go on the end of the rear axle and are clamped to the bike by the wheel bolt.  But on an e-bike with a rear wheel motor, you might have a cable coming out of the axle on the side you want the trailer.

If you google images for "bike trailer adapter" you'll get a bunch of ideas for adapters you can buy, and if you look for "homemade bike trailer adapter" you'll get a bunch more ideas for workarounds you can use if a stock item won't work.  Again, it depends on the bike and how much scratching or other damage you're willing to risk, but I see a bunch of pictures using hose clamps to attach something to the stays that a trailer coupler can then attach to.

We jury-rigged something on our cheap ebike many years ago: we didn't care about scratching and we figured it was pretty cheap steel but strong enough so we clamped the trailer coupler on with a U-bolt.

This is the best picture I can find of the bike with the coupler U-bolted to a seat stay:


Best Time to buy new bike? I have been looking around bikes for a while tried about 10 bikes already and rode about 10 miles on each of them and I think I have come to a conclusion about which one to buy (or did I?)
But the question is when is the best time to buy a new bike.
I assumed that Winter is the best time because most of the people are not riding and companies are trying to sell the old stock off to restock.

So I had made up my mind to buy a certain bike but then heard from the LSB fall is the best time because this is the last price they would reduce on their bikes.
So are they right?
Should I get my bike now or should I wait till winter to see the prices going down further?
I live in Chicago

Any comments and suggestions are appreciated

Thanks in advance

The best time to get a new bike will vary somewhat due to your region's climate and population density. Bike shops in warmer areas and very large cities are going to sell bikes for sticker price pretty much year round. In regions with a cooler off-season, there will likely be bike shops selling bikes at a discounted price, since they don't move as much stock when riding conditions aren't as nice.

But a pretty universal trend is for bike shops to mark down old model year bikes to help get rid of them and make room for new bikes. New models typically come out between September and November, but some will debut as early as late July, depending on the company.

The best time to look into getting a new bike, then, is usually at the end of the cycling season (mid autumn). You might not want to wait until winter because that's when a lot of shops are looking to keep their stock limited to their best-selling, general-purpose and/or entry-level bikes, since most people don't want to buy anything especially exotic right as snow and ice start becoming a factor (they'd have few opportunities to ride).

If you were to expand your search to used bikes, you would be able to find a whole slew of them in springtime when a lot of people are switching up to new bikes to get ready for a new season.

You may occasionally find two or three model year old bikes sitting in the corners of shops marked down to dealer cost just because it was an odd size or unpopular color, but usually shops aren't going to go super deep on their bike discounts since bike profit margins are typically only between 30% and 45%, and they can't burn up too much of their profits trying to move units.

Your LBS informed you correctly -- Fall is the best time to look for a new bike if you're on the hunt for a new deal and not concerned about the newest and coolest tech.


How do I calculate the power required to climb a hill at a given cadence? Suppose I ride at a cadence of 50RPM for 10 minutes with a 39x23 gear ratio on a hill with 10% grade. Is there a simple formula to calculate the power output required?

You don't quite supply enough information in your specific question (that is, "50RPM for 10 minutes with 39x23 with 10% hill") to provide a full answer in absolute terms but, if we assume you're riding a standard sized 700c bike there's enough information to make a good estimate in relative terms.

First I'll give a short answer, then a rule of thumb that's easy to calculate and will put you within about 10%, then a longer more detailed answer.

The short answer to your question, in relative terms, is ~ 3 watts/kg of total mass. To convert that to total absolute watts, you just multiply 3 watts/kg * total mass (in kg) for you, your bike, and all the equipment you're carrying. For example, if you weigh 70 kg and your bike and all its equipment together weigh an additional 10 kg, it will take approximately 3 * (70+10) = 240 watts. If you weigh 70 kg, that would mean you would need to produce 240/70 = ~ 3.4 watts/kg of body mass.  To put that into context, 3.4 watts/kg for 10 minutes is not a bad amount of power output for a casual recreational cyclist; on a normal walk on flat level ground people average around 1 watt/kg, while a pro cyclist might be able to average in excess of 5 watts/kg for an hour. It has been estimated that Lance Armstrong produced slightly over 6 watts/kg for 40 minutes in climbing Alpe d'Huez during the Tour de France.

A rule of thumb to use to convert speed to power on steep hills is this: On a steep hill, multiply the hill's gradient by your speed in km/h, then by ~ 3. If you measure your speed in mph, multiply by 5 rather than 3. That will give you a ballpark estimate of the watts/kg you need to produce. For example, if you are climbing a 10% hill in a 39/23 gear ratio at 50 rpm on a standard sized bike, you're traveling at ~ 11 km/h (or around 6.5 mph). So 10% * 11 km/h = 1.1, and 1.1 * 3 = 3.3 watts/kg. Alternatively, if you measure speed in mph, 10% * 6.5 mph = .65, and .65 * 5 = 3.25 watts/kg. Basically, all you have to remember for this rule of thumb is the number 3 if you measure speed in km/h, or 5 if you measure speed in mph.

How did I convert your cadence in a particular gear to speed? On a standard normal-sized bike, the "700c" rear wheel has a circumference ~ 2100mm (= ~ 2.1 meters). If you were pedaling at 50 rpm through a 39/23 gear, then (50 rpm) * (39/23) * (60 minutes/hour) * (2.1 meters) = ~ 10700 meters/hour, or 10.7 km/h, or 6.6 mph.

And now, the fuller explanation. The equation to convert speed to power is well-understood. Total power demanded has four parts:

Total power = power needed to overcome rolling resistance +
              power needed to overcome aerodynamic resistance +
              power needed to overcome changes in speed (kinetic energy) +
              power needed to overcome changes in elevation (potential energy)

Of these, the simplest piece is the power needed to overcome changes in elevation which, fortunately in this case, is what you were asking. On a steep hill, your speed is low and the aerodynamic and other resistance forces tend to be small relative to the climbing part. The power needed to account for the change in potential energy is straightforward:

watts(PE) = slope * speed in meters/sec * total mass * 9.8 m/sec^2

or

watts/kg = slope * speed in meters/sec * 9.8 m/sec^2

So, all we need is to get speed in m/s. If you have a cyclecomputer that reads in km/h, you need to divide km/h by 3.6 to get m/s and multiply by 9.8. If your cyclecomputer reads in mph, divide mph by 2.25 and multiply by 9.8. If you do this, you'll see that the resulting constants are approximately 3 (for km/h) and 5 (for mph), as stated in the rule of thumb above.


Is a name sticker with my name enough to prove a bike is mine if it gets stolen? Apart from the fact that stickers can be removed (as thats not the point of my question) would if my bike got stolen and i found it, would a sticker with my name on the frame be enough to prove that the bike is mine?

Thanks.

It may be better than nothing, but no.  There are free registries online that you can use to register your bike's serial number.  The shop where I purchased mine set me up as a part of the purchase.

Some home/renter's insurance policies require you to have pictures of the bike along with the registration. Pictures with a datestamp could help prove how long you have had the bike.


Could i break Shimano Nexus 7 with no cable attached? Is it possible to ride (pedal) on bike with Shimano Nexus 7 with no cable attached?
Is it possible to push the bike without pedaling, when cable is unattached, or setting of shifter is not correct?
I am asking, because at my last ride the setting of hub got wrong and i had no tools, so i push the bike home. (Cable was attached, but setting was completely wrong) Now i hope i didn't damaged inner mechanism. Or did I?
Thank you and sorry for mistakes (not english).

Yes, that's fine.

You won't damage the hub that way, although you might damage the cable attachments if they get caught in the chain, or lose some pieces. Single cable systems work by pulling and releasing the cable, and one gear is always "cable completely slack", just as it is when there's no cable there. Like what you did.

It's just like a rear derailleur system in that regard - without the cable the spring in the derailleur pulls it to the highest gear, and it just sits happily in that gear while you ride. Your hub is similar, except that the spring is inside the hub where you can't see it.


Ride a Century Without Stopping? Under what circumstances would it be advisable to ride a century without stopping?

If a person had: 100% daylight; no mechanical failures; and, no stop signs or lights to deal with, it would seem possible that she/he could ride 100 or more miles on a bicycle without ever putting a single foot back on the ground.

Given the above assumptions, I'm wondering what other conditions make it favorable for a rider to forgo all stops.  Apart from the above mentioned perils, it would seem to me that nutrition, hydration, waste disposal and arm fatigue would be the greatest challenges.

I've almost done this, and its not "easy" but it should be possible.

However a non-stop 100 km is much harder than simply doing 100 km.  Try working up do it.  I don't know what your current distance is for a "big ride"  but start with 25 km non-stop, then work up to 50, 75, and then 100 km.

Leave early in the morning on your big rides - it seems to help the distance go by easier.  Having twilight close in is a bad feeling.

Also, its cooler in the morning and you can stretch your water further.  Pre-hydrate, carry food, eat the food (!), and pace yourself over the distance.

Weather, specifically winds could be a big difference between a fun ride and a torture.  Consider reading your local meteorological service predictions that morning, and try to pick a route that should have a tailwind out, and a tailwind back.  This

If you can go with a group, that will help your speed, but increases the chance of someone having a reason to stop.   You could lay a challenge, something like *"Ride from Zeros to Little River and back to Zeros without putting a foot on the ground and I'll buy coffee for everyone who does it."

Climbs will cause you problems, and a route that is significantly more downhill will feel like cheating.  An Out-And-Back will make rises equal descents.

I'd also draw a distinction between stopping because you need to and stopping because you have to.  Red traffic lights means you have to stop,  You might be able to drift up to the stop line at minimum speed and stay in the saddle till the light goes green, but that's chancy and duplicated for each set of lights you pass.   If there's an accident, you stop and help and forget the challenge.

Personal stories - I've done a 100 km ride called Le Race.
https://www.strava.com/activities/520613679/analysis
It has over 2km of climbs too, and while the first half was great, the last half turned into an endurance ride instead of a race.  I had one stop at a red light before leaving town (despite roads being "closed") and one long stop with a puncture.  After halfway I stopped at every water station because I went through 12 full bottles of water, but was only carrying 2.

Separately, I did a road ride by myself for 146 km that was a "great loop" around Christchurch, Rangiora, Oxford, and back via the Waimakarerei Gorge.
https://www.strava.com/activities/694129685/analysis
I had one big stop in the middle of that at my Nana's house at about 75 km.

The takeaway is, can you sit on your bike for 5-6 hours solid ?


Is it possible to construct an overnight shelter using a bike as the upright? Next year I might find myself needing a lightweight touring/camping shelter, suitable for overnight stops at camspites and at the roadside.  One option is a single-hoop bivvy tent (example) but many of these aren't much lighter than my hiking tent, and they're rather expensive.  A hoopless bivvy bag seems more like emergency kit to me (with the exception of the Salewa which allows the hood to be lifted with a cord to a branch, fence, or bike). My choice is rather restricted by my height -I'm too tall for many of them.  We can assume a decent weather forecast before setting out for a few days, so some need for rain-proofing (and face cover) but not planning to be out in a storm.
As an alternative I wondered about getting a tarp, and using the bike itself (held up with guy ropes and possibly a kickstand) to lift the head end.  This would have the advantage of no poles to carry, making packing very easy. Has this been done before? Are there any plans in existence? I've got reasonable DIY/craft skills and equipment but not really for working on fabric beyond minor modifications.

Yes, its been done before, there are various configurations.
Google for 'Bikepacking tarp shelter' for many ideas.

Good resources for this type of thing are
bikepacking.net forums and in the UK Bear bones bikepacking.

Here are some examples:


Does my fixie need a chain tensioner I'm building my own fixie (almost a cliche, sorry) and I debating whether or not to buy chain tensioners.  I will be riding my bike with a fixed gear most of the time.  One of the reasons I ask is because I see a lot of fixies without them.  So I was wondering whether or not I really needed them.  Personal preference is welcome.

You don't need a chain tensioner (by this, you presumably mean something like the Surly Tuggnut and not a pulley which will snap on a fixie). This article from Lennard Zinn (or equivalently, the one he cites from Sheldon Brown) covers how to tension your chain.


What shifters are compatible with shimano 9-speed? I haven't ridden in anger since around 2003. I have two bikes which I am trying to return to a roadworthy state. Each has a non-functioning right hand shimano shifter.

Racing bike: Ultegra 6500 (9-speed), double chainring
Training/winter/touring bike: 1055 (8-speed), triple chainring

I'm thinking that it would be cost-effective to convert both to shimano 9-speed, as parts (shifters) are likely available second hand, and I have a spare Ultegra 9-speed rear mech that I could stick on my training bike.

Is there a good history of shimano groupsets, so I can work out which 105/Ultegra/Dura-Ace groups were 9-speed?

I see that modern shimano groupsets have handlebar-routed gear cables. Are there any 9-speed compatible shifters which have this? (I remember that there used to be a method for converting campagnolo 10-speed to shimano 9-speed in order to gain this advantage, which I'd be willing to consider if I knew the relevant components.)

In summary, two questions:

which shimano groupsets were 9-speed?
do any shimano 9-speed groupsets have handlebar-routed gear cables?

...or please direct me to somewhere that will tell me this information.

According to the Wikipedia page, the following groupset variations were specifically 9-speed:

Dura-Ace 7700 (1996-2002)
Ultegra 6500 (1997-2004)
105 5500 (dates unknown)
Tiagra before 4600 (before 2011)
Sora 3400 (2012-)

As far as other components go, it seems that as long as the cassette, chain and shifters match then the groupset should work. All Shimano rear derailleurs (excluding early Dura-Ace) have the same shift ratio, so they should work so long as the derailleur has enough travel capacity - use one rated for the same or higher number of gears than in your cassette.


How can I keep my chain from falling off the inner chainring? (specifically, from getting stuck in the bottom bracket) I've got a mountain bike which occasionally drops the chain off the lowest gear, and then the chain gets stuck in the bottom bracket.  This happens while pedalling.

Once the chain is there, it takes either a lot of pulling (potentially bending the chain), or removing the crank to get the chain out.

Either way, it's a pain when it happens on the trail.

Note: I'm not talking about chain suck.

And I've seen products like the Deda dog fang chain watcher and Jump Stop, anyone have any experience with these?

There is a bottom limiter screw on the front derailleur which may be of some help. Tension it up till it just goes far enough to shift. It's also possible that your rear derailleur isn't taking up the chain slack properly and is letting it bounce as you go over bumps. This would cause the bottom of the chain to slap as it goes forward to the front ring and could cause it to come off. In that case you might see about replacing the rear derailleur with one on which the tension springs are newer and reduce the slap.


Giant SCR 2015 upgrade options? I have a 2015 Giant SCR2. That has Shimano Claris. Outdated by now 2x8. I’m thinking of an upgrade to Shimano 105 5800 or Tiagra.
Which one will fit and do I need to change the wheel?

Regarding ‘which [groupset] will fit?’ Bicycles are generally so standardized that you can swap out groupsets easily and only have to deal with one or two areas of compatibility.
In your case you need to consider the rear wheel. The freehub body for 11 speed compatible hubs is 1.8mm longer than those for 8-10 speed. You’ll have to examine your hub too see if yours is 11 speed compatible. If there is a 1.8mm spacer behind the 8 speed cassette the hub will be 11 speed compatible.
Generally you also need to look at the bottom bracket for crank compatibility. As you have a ‘3-piece’ crank with cartridge bottom bracket you can easily replace that with a Shimano HollowTech external bearing bottom bracket, which all Shimano road cranks are compatible with.
Rim brake groupsets are relatively inexpensive, but most of the time it’s not worth upgrading the groupset on a bike. Often it’s better to sell the current bike and purchase one that is a complete upgrade, especially when you factor in the cost of special tools you need, or paying for a bike repair shop to swap out the components.


Bike tires need air every ride...is this normal? I ride my bike maybe once a week at most. I need to add air to the tires every time to bring it up to the right pressure.  (I ride a mountain bike and I put about 45 - 50 PSI's into the tires.)  Is this normal?

If you're putting in 5 or maybe even 10 PSI every week, that's not too much out of line; it's normal for tires to lose a little bit of pressure over time.

If your tires are sinking down to much more than that, you may have slow leaks. If both tires are decreasing by the same amount, perhaps you have older tubes that need replacing. If one tire is doing this but not the other, you may have a very slow leak. Try replacing the tube and see if that fixes the problem.


Servicing / replacing headset The headset on my daily commuter is foobared. So I'll be looking to service it, possibly replace as many of the low-end components with better ones.

As I've learned the hard way, it's the questions you DON'T know to ask that really burn you if you go out and buy a bunch of parts without the full info.

The frame manufacturer's specs are virtually non-existent, which is pretty much to be expected for this cheap frame.

What info / measurements do I need to know in order to replace my headset, and, how do I acquire this information (ie: what are the critical spcs and how do I measure / determine them on my own)?

You gotta know your SHIS! :P

First you will need to determine the type of headset you require. It may be integrated,zero stack, External cup,as well as threaded or threadless.

After having this information the measurements you will require are Inside Diameter of the head tube top and bottom. This measurement allows you to determine what type of fork you need, whether 1-1/8" , 1-1/4" or tapered from 1-1/8" to 1.5".

The measurement of the steer tube Outer Diameter on the fork, top (stem clamp 1-1/8" or 1") and the bottom OD (Crown Race Seat Diameter). Bearing seat and angle will also be needed if it is a threadless headset. You can usually just look at the old bearing to get this information if the side marking are still readable.

Cane Creek and Park Tools website both have a plethora of information regarding it. This poster from cane creek may help clarify.

See the larger version here
Cane Creek's wording:

  The system addresses the critical interface dimensions required to fit a fork to a frame, as well as bearing location/cup type. To determine fit, four dimensions are needed: (1) stem-clamp diameter of fork, (2) crown-race seat diameter of fork, (3) head-tube top inside diameter, and (4) head-tube bottom inside diameter. Bearing location and cup-type are identified as (a) external cup (EC), (b) semi-integrated or ZeroStack (ZS), or (c) integrated (IS).

More info:

Park Tool
Cane Creek


KMC chain disconnection issue I'm trying to replace my rear derailleur on my cheap MTB. Chain is a KMC with a Z and NARROW on it. There's no master link so I bought a tool but i can't get it to push a pin out. Are the pins one direction?
Thanks, Justin

Pins can be forced out from both sides.

Quite a lot of force needs to be put on a pin to force it out, especially at first to move the pin out of its interference fit in the outer chain plates.

Make sure the chain is positioned in the chain tool properly, and the driver is hitting the chain pin straight-on. If you have a small chaintool, such as one from a portable tool kit, you won't have much leverage. You can hold the tool with a large adjustable wrench and turn the handle with pliers.

Don't be afraid to really force it. IF you are replacing the chain you wont break anything you care about.

If you want to re-use the chain you need to careful if you have unsuccessfully tried forcing more than one pin out. You may have moved a pin slightly and weakened it. If you suspect you have done this a new chain may be a safe option.

I linked a Park Tool video on replacing a chain below that includes how to break a chain.


SR Suntour XCM v3 forks Headset Currently building a new mountain bike and for the time being I'm using the old forks until I buy some new ones.

My question is how do I find out what type of headset I need? Because from my understanding there are quite a few different types.

Update: I have uploaded a couple of images. It looks to be integrated, as there are bearings/cups already in the frame and threadless. The steerer/stem width is 1 1/8th.

I think that solves my question.

There are a few factors to choosing a headset, primarily frame related:

Does the frame require a threaded (1") or threadless head set?
What is the headtube/ steerer type (1.5 straight, tapered, 1 1/8 straight)
Is the headset integrated (cups sit within the frame)?

Deciding if a fork will fit is a bit easier, is the steerer the correct length (it can be longer, you can use spacers above or below the stem for fit) and is it compatible? You can get headsets that interface some head tubes to steerer they are tapered steerer in 1.5 head tube or 1 1/8 steerer in tapered head tube.

Firstly identify what headset you need first and work from there. Cane Creeks headset finder is a good start.


How do I match motor and battery leads on a generic e-bike conversion kit? This is for a "Generic Add-on Motorize Bike 48v 1000w 26 Inch Front Wheel Electric Bicycle Motor Conversion Kit."

How do I find connectors to the motor and battery that are compatible before I buy them for this bike? I am not talking about voltage or wattage. I just want the connectors to fit without splicing.

Based on the info you've presented, its "cross your fingers and hope"

Can you tell us anything further about the motor, motor kit?  Even a manufacturer could help.

My ebike kit used 7 pin DIN connectors with a screw-on barrel lock ring.  The battery connectors were generic automotive spade connectors.

If you're choosing a connector, then voltage and current (ie wattage) is relevant, as is whether you want to hot-connect them.  Plus you need something that is water resistant and vibration tolerant.  (note spade connectors are neither of these... guess how I know that!)

Final thought - you're talking about a kit.  In my mind a kit comes with everything you need to do the job, possibly excluding batteries themselves.  However any parts not included will be common and well-described.

And what's wrong with a splice?  A properly-done connection will outlive the wire.


Bottom Bracket size issues I need to replace my bottom bracket on my giant rapid 3, the BB is a    FSA BB-7420ST - 116mm (68x116mm), but it's hard to found or not available.

My Question is: can I use a BB in 68x115 or 117mm (much more easier to found)? No big problem in perspective?

Yes, you can use the suggested alternate BB cartridge sizes.

The thread (68mm) has to match precisely, but the width of the axle can vary.  The problem is whether 1mm more or less will affect your chainline on the drive side.  Relatively minor changes can upset the extreme cross chain positions.

So if you're a big-back-cog rider, get the narrower BB, or if you ride a lot on the smaller rear cogs, get the wider BB.


Low-height rear rack for Bike Friday New World Tourist folding bike I'm looking for a rear rack for my Bike Friday New World Tourist (20" wheels). I've come across a bunch of rear racks like this one that sit high above the wheel. But I'm searching for one that is not so high - I want a lower height rack that will not block my rear light (clamped to the seatpost) when I put my bag on top of the rear rack and that will let the weight of my bag sit lower so that I have a lower center of gravity.

Where can I find this?

The Biologic Portage Tern seems to fit the bill.


What is the name of this small component inside Shimano Tourney STI What is the name of the component outlined in red in the image, that seats the head of the brake cable?

This part is officially called "cable hook" and "cable hook unit" in Shimano docs. See attached image (I won't link it because the PDF is not hosted by Shimano) and this document (page 7).


Preload Adjuster Use on SR Suntour XCM I've got an SR Suntour XCM HLO 27.5" 100mm travel that comes with my bike. It has preload adjuster on the left and lock on the right.

What I wonder is how to properly adjust the fork softness/stiffness as I encountered some bumps with stiff feelings on the fork.

Also, if I lock it and turn the preload adjuster, I can turn it more than if I let the fork open. What causes this and should I lock it before adjusting the preload?

Turning the preloaded dial towards the negative symbol will decrease the preload on the spring. Therefore if you find the forks are too stiff, backing off the preload will soften the fork. Alternatively if you wish to firm up the fork, turn the preload dial towards the positive symbol. This will compress the spring and stiffen up the suspension.

I would adjust the preload with the lock out off, though I don't believe it would make any difference beside allowing you to compress the fork as you dial preload on/off to see what affect it has on the fork.

Hope that helps!


Can replacing my handlebar tape help reduce finger numbness? Despite changing hand positions often and switching to more "cushiony" gel gloves, I'm still experiencing intermittent numbness when I ride (sometimes I get tingling and sometimes not).

Are certain types of handlebar tape likely to help? The tape on my bike is several years old. I see gel and cork tapes (and those that claim to be both gel and cork), neither of which I have tried.

I realize that I don't actually know what the real purpose of handlebar tape is (perhaps that's another question). It might be that it is only for helping you keep a grip on the bars when they get sweaty.

Hand numbness or tingling can happen for a variety of reasons. It could be a matter of fit, or simply tape or the handlebars themselves.

Bike fit:

How's your riding posture? If you're putting too much weight on your hands, it could be because you need to raise you saddle to allow you to put some of your weight on your legs. It's also possible you just need to tilt it a litte. For example, I know that I put a little weight on my butt, even though I try to put most of it on my legs. My hands are happiest when I tilt my saddle so I'm almost sliding forward, but not quite. The point here isn't that you should do this; everybody's bike and body are different. (Well, some people have the same bike as others.) But minute changes can have a huge effect.

Saddle height can also be a matter of trial and error. This answer gives the skinny on saddle height, although experimentation is always helpful. This question talks about bar height relative to saddle height.

Is your bike sized correctly? If the distance from the saddle to the bars is too great (or too small), that could cause other problems (namely, making it difficult to get a good fit in the first place). You can get a rough idea of this by checking that your standover height is correct, although this is a very rough test.

Bars, hands, gloves, and tape:

Angelo's answer gives a good overview of bar tape, and cork-vs-gel tape. In addition, I've heard that gel tape tends to wear out quickly, as the gel slowly migrates away from where you rest your hands. (Gel saddles have similar problems.)

Another option is double-wrapping the bars; some people swear by it.

You can also get padding for your bars that you stick to the bars before wrapping. I tried it and while I personally didn't feel any difference, some people love the stuff.

Are your bars an appropriate width? A good rule of thumb is that they should be as wide as your shoulders, although this can translate into some very wide bars, particularly with stocky men. (Ahem.)

Lastly, don't forget that padded gloves can help. Sometimes, when your hands start to hurt a bit, it just means that it's time for some new gloves.

In conclusion:

Hand pain is, unfortunately, a problem that many cyclists fight for years; others lick it immediately or never encounter it. Don't be afraid to experiment with the goal of making yourself as comfortable as you can on the bike.


Does having machined brake surface on rims matter? I'm looking at getting a wheelset with disc hubs and rim brakes to run on my disc and non-disc cross bikes. There are stock wheels that have velocity a23 rims, which are a poupular rim brake compatible rim. However, the stock wheelset tend not to have machined brake surfaces.

Is not having a machined brake surface a problem?
Does it matter whether the rim is painted or anodized?

Update:

It seems like some old heads seem to think that a machined sidewall was a marketing gimick made to stop brake squeal on new showroom bikes. Rivendell sell a lot of rim brake wheels without a machined surface.

Jobst Brandt via Sheldon Brown:
http://sheldonbrown.com/brandt/machined-rims.html

Rivendell (probably via Grant Peterson)
http://www.rivbike.com/kb_results.asp?ID=52

Rim walls are machined, if not for aesthetical or marketing reasons, to give the braking surface of rims most regular shape possible, removing small irregularities which could cause "hard spots" while braking, specially around the seam (spot where both ends of the rim are connected together during manufacturing).

Also, it seems to me that the residual grooved pattern improves braking power, most probably due to increased contact surface and possibly dirt clearance issues, without noticeable increase in pad wear, but I have no objective data to support this impression except a positive personal experience with a handful of machined-wall rims with v-brakes.

Hope this helps.


How to upgrade disc brake size My new bike has disc brakes, and the front brake leaves something to be desired. I want to upgrade to a 180mm front rotor. Do I need to change any components besides the disc itself and an adapter for the caliper? Also, which adapter would I need? I currently have a 160mm 6-bolt disc installed, and the caliper is mounted on a 160mm post mount.

The fork in question:

Answering the question: To upgrade to 180mm from 160 you need a Post-Post 180mm adapter and a new disc. The adapters are widely available as 180 is probably the most common sized front disc on MTB's.

I think the question that should have been asked is "My front disc is not working as well as I think it should, how can I make it better". As many say, its not size that counts....   (I could be wrong, maybe you just want to do the bicycle equivalent of stuffing a sock down the front of your pants, in which case, go for it, no need to read on)

A bigger disc is a cheap way to make cheap crap brakes work better, but they are still cheap brakes, so manufacturers have sold us the idea that you need big disks because its cheaper to make big discs than good brakes. They then go on to sell the idea that by spending more money, for the same weight you get better brakes.

If you have cheap crap brakes a better (although more expensive) option than a bigger disk is upgrade to better brakes. If you have good brakes then something is wrong if they are not performing well and you should address the performance problem (poor bedding in, contaminated pads etc).


replaced tire, now wheel flexes side to side I have an 85 Raleigh that until yesterday had never had its rear tire replaced over the life of the bicycle. Before I replaced it, the wheel seemed fairly stiff. I don't know if the old tire was so dried out it ed lending support or what.

I'm wondering if I need to get something adjusted or if a bit if flex is ok. Is this normal?

Edit: by flex, I mean I tightened down the bolts, so the axle is tightly locked to the frame. However, when I first took the bike off the rack, the tire stayed in the same place on the ground, but if I shook the seat side to side, it would hit a frequency where the axle would move side to side, but the rim would sort of flex backwards and forwards.

Also, by stiff I meant it didn't do this before, not that the brakes were rubbing or anything.

Edit 2: There were questions about how well maintained this bike was, the previous owner said it was used as an indoor exercise bike, and when I bought it it it was on the bike exercise stand. It didn't have a front wheel, and based on the wear on the rear tire, I don't think it was used much, so as far as I can tell, it just sat in someone's basement for 30 or so years.

There should be no flex.

It's possible you haven't reinstalled the wheel correctly; and the axle is sliding around in the dropouts. If that's not the case, I assume you're talking about lateral wobble when you hold the bike frame still and wiggle the wheel rim. That indicates hub bearings in dire need of replacement.

You say the wheel felt stiff before replacing the tyre; the chances are the tyre/rim was rubbing against the brake pads. In changing the tyre you most likely knocked things about a bit and nudged the brakes so that they no longer rub on the tyre/rim, exposing the play in the hub bearings that was already present.

Much less likely: If you're talking about a different kind of flex (i.e. the wheel rim is actually deforming under moderate force), you've probably cracked the rim while replacing the tyre.

It sounds like a trip to your LBS to me. Wheels should not flex in any of the ways described above, and a bike which hasn't had a tyre change in 29 years will almost certainly have been neglected in other ways too. You don't seem to have a great deal of experience, and most likely won't be able to spot potentially dangerous problems. Take it in and ask for a full service.


Does crank length affect the number of gears a bicycle needs? When I was a child I noticed that as I out-grew my bike (or when I rode a smaller child's bike) I felt like I could accelerate better. The smaller bike seemed 'nippier', and in hindsight it was similar to driving a diesel with quite a flat torque curve. I now imagine this is what it would be like to ride with short cranks.
So the question is: if I rode with 135mm cranks could I get away with fewer gears than when riding with 175+mm cranks?
Edit:
I have read a similar question now. It doesnt address the biomechanics of how cranklength effects the varying proportion of glute and quads during the rotation. The closest this was addressed was in a comment to that question that noted the difference between doing a half squat and a full squat. I feel long cranks tends to a full squat, which feels weak.
The gain ratio is valid but fairly intuitive.
It would be great to find papers that reference anatomical models that have muscle length force functions coupled with the thigh and shin bone levers that can be converted into graphs of force/torque  contributions of muscles at the pedal over a whole cycle for varying power levels and cranklengths.
Or experimental data on max cadence range at which varying power levels (say 50%,60%,70%,80%,90%) can be maintained for different cranklengths.

Not really. You might want different gears, but probably not fewer.
Shorter crankarms give you less mechanical advantage—they're functionally equivalent to being in a higher gear. So you might want a lower gear range to compensate.
It is common to express mechanical advantage as "gear inches"—this is
(front sprocket/rear sprocket) × wheel diameter
This obviously doesn't account for crankarm length. Sheldon Brown proposed a measure he called the gain ratio that would do exactly that:
(front sprocket/rear sprocket) × (wheel radius/crankarm length)
From this, you can see that wheel radius/crankarm length will typically be about 2. If the denominator is smaller, the quotient is bigger, so for a given set of gears, the net gain ratio would be higher. For that reason, you'd probably want a  proportionately lower gear range.


Does anyone know what brand and model is the bicycle in photo? This photograph is from early to mid 1960. Any ideas as to what this bicycle is? This has been bothering me for decades. Can't find anything like it anywhere.

It's a 1961 Hawthorne Twin Bean Tank Bike sold by Montgomery Ward.

1961 Montgomery Ward Christmas Book page 180
Here's one in the wild

ratrodbikes.com
The model was sold in 1960 and 1961. The 1960 version has slightly different graphics.

The Hawthorne bikes were made by CWC (Cleveland Welding Company) the maker of the Roadmaster bicycles) since 1934, and were distributed by Montgomery Ward across the country.
american-vintage-bicycles.com


Why my innertube is so big So my old tyre had markings 32-622 and 700x32c. I bought new tyre with those specs and that is fine. It fits perfectly on the rim.
But I bought inner tube with those specs and it seem it is way to big for the rim / tyre. I'm a missing something? What is the correct size inner tube for this tyre?

The sizes match, so according to the manufacturers you are on the safe side.
It’s not uncommon for tubes to be slightly too “long” (i.e. have a wider diameter). Maybe it’s because this tube also fits 635mm wheels and not just your 622mm.
Just try to “distribute” the excess length, so you don’t have one big kink in a single place. In your photo it’s also not fully inside the tyre.


How to train front braking technique? One of my mountain bike buddys has severe issues with downhill riding technique. By downhill I don't mean downhill racing in this context but riding down trails that are rather smooth but with some roots and rocks or short bits that are really steep and require to take one's heart in hand and get one's buttocks far behind the saddle. He has taken a fall over the handlebars some time ago and since then is even more cautious in those things.

By chance I learned that he is mostly braking with his rear brake even on flat terrain because he is too anxious about another rollover. I think I have figured out that this non-use of the front brake is the main reason for his downhill issues as the rear brake does by far not provide enough power and control here. I would like to get him back to using the front brake more and to give him more confidence and fun on downhill sections. Unfortunately I don't know how to do this.

I don't know if he's really aware of his problem yet (hadn't time to talk to him since I figured out the problem myself) and I don't think he has time and motivation to do just stupid practicing sessions somewhere in a park or another "boring" location. So I would be especially be interested in small exercises one could easily include into the weekly ride.

Lets get the social aspects out the way - you can lead a horse  to water and all that stuff.....: Hows your relationship - will he listen to you and is he prepared to take clearly well intended advice. Also does he believe he has a problem and does he want to fix it. If any of these answers is no there little you can do except ruin you friendship. Till hes ready, wait at the bottom of the hill for him, cut him plenty of slack and make sure you both enjoy the riding - if appropriate laugh with him, but never at him.

After a night in hospital and metalwork keeping my wrist together, it took years for me to be able to ride a track with large drop off to the side - especially the right - comfortably, yet and off over the handlebars never phased me. After a big off you subconscious needs to be convinced you will not be hurt if it happens again, or it will not happen again, the only way it learns is through repetition without the consequences. You mate has learned hitting the front brake throws you over the bars, so his subconscious will not let him do it.

Presuming hes ready to learn, the and hes is willing to learn from you - Look online for some videos - watch for the rubbish that is out there but you seem to know what you are looking for so should be all right there.

Chose something he can currently ride comfortably, that you ride faster, with more control and/or more comfortable. Ideal would be a could of tight switchbacks that can only be ridden fast using the front brake to slow into them, yet back only braking merely means you have to go in slower. Safe run out if you don't make it is essential, bonus if its a lake or river that gets you wet or in front of a big crowd of onlookers who will give a good cheer at the screw ups.....The idea is to get something that is safe (physically safe as well mental and ego-safe). He needs to ride something that is not doing in his head, that his subconscious is going "bring it one, this is easy" while his conscious is think how to do it faster/better.

If possible video you and him riding it on the first run and keep it for later. Point out where you are braking differently and ride it for a half day. Each time, both of you try to go faster/more controller/better. If you get bored or it gets too easy, find another spot just a little bit harder.  The aim is ride technically easy ground perfectly before progressing to harder sections.

At the end of the session, review the video of the first and last run over a beer....

Work out if you are going to mix this in  with some rides, at the end of a ride is good, but make it really easy as your both tired. A special trip is well worth it.


dropper post not working at freezing temperatures Over the past winters I noticed that my dropper post (rockshox reverb) stops working around 0°C (32°F). I usually manage to lower it one last time but then it doesn't rise anymore upon pushing the button (I ensured several times I'm pushing all the way down and tried keeping it pushed for a minute). Once after the ride back inside, it starts working again.

Is that a known feature?
Any suggestions for mitigation?

The reverb, much like Shimano brakes, has a known issue when operating in the cold. The oil inside simply thickens too much to properly flow through the lever and hose. The oil flow through the damper also gets constricted. I don't think there's really a solution because switching to a thinner oil might cause issues in the summertime, such as the post rebounding too quickly and damaging internal components. Of course, you could switch to a different dropper with a more modern design that does not suffer from that issue.
Do NOT pull up on the reverb when it is compressed, even if the lever is being pushed. You will suck air past the seals and cause the infamous "Reverb squish" (where the post is no longer capable of staying rigid thanks to air being mixed in with the oil, and you basically have a very expensive suspension seatpost. Cannot be fixed with Viagra.)
Edit: If your particular model has it, try turning the speed adjuster to full open/fastest. That might help.


Is losing power when pulling Shimano GRX lever a bleed problem? Recently I had an accident on my bike, and my front brake 11-speed,  front brake GRX 600 shifter isn’t braking well anymore.
The shifter took a bit of damage in the fall. Initially it didn’t shift, and I had to bend the edge of the lever arm (under the “X” of the GRX logo) outwards to stop it fouling on the inner shift lever. Shifting is fine now , but there are problems with the hydraulic brake.

The brake seemed fine. Pulling the lever it feels firm and brakes confidently. The problem is that the brake power fades and the longer you pull the lever the more it pulls in to the handlebar. Over a fairly short descent the lever can be pulled past the bar and the pads aren’t pressing on the disc anymore. Releasing the lever and squeezing again gives another firm/confident brake, which then eases off again.
My first thought was that this is a bleeding issue, so I picked up a bleed kit and gave it a go. This didn’t solve the problem, so I went through the bleed process again, to no avail.
There’s a good chance I’ve just failed to bleed it correctly. The handlebars are ridiculously aggressive gravel bars, so rotating the shifter to the correct position to “burp” it was a challenge. Also, I noticed a few tiny bubbles in the syringe of mineral oil (it was new).
Do the symptoms above sound like a bleed issue, or something else? All the advice I’ve found on the internet about air in the system and bleeding seems to suggest braking will be spongy but “pump up”. That’s not what I’m experiencing.
It’s seems impossible to get hold of Shimano GRX components at the moment, so I’m really keen to fix this even if it just holds me over until it can be replaced.

The symptoms you are describing seems to be a "Ghost Leak" - Rides of Japan terms it this way. It might actually just be a kink in the hydraulic hose.
His symptoms are similar. Squeezing the brake feels powerful, but holding on to it will eventually cause the hydraulic pressure to release. Once he lets go of the brake lever, and squeeze it again, he can feel the power again.
Definitely recommend you checking out Rides of Japan's recent video on this, it's quite in-depth as he shows why it happens.

In short, over a period of time, the points where the hydraulic hoses get kinked will wear out over time. Especially if there are accessories like handlebar bags there actually slightly re-route the hoses' entry into the frame/cable guide. As the hoses are under pressure from the hydraulic fluids, eventually the inner lining will disintegrate, causing a kink.
In your case, could it be that the hoses actually got hit in the accident? It might be ideal to replace the hoses too! If really there's a kink in the hose, it won't be apparent from the outside too.
Rides of Japan is quite thorough for this issue (for a home-mechanic at least), it's easy to understand from his documentation! Hopefully, this is the correct approach to your issue, good luck!
P.S. I mentioned Rides of Japan like 3 times, but damn it his videos are binge-able!


Is there such a thing as a 25mm crank puller? I have a BMX with a Primo Pro crank on it that I need to remove.

The thread in the crank arms that the crank puller would normally screw into has 25mm diameter but I only seem to be able to find 22mm crank pullers.

Do crank pullers come in different sizes or is there some sort of adapted that I can use with a standard crank puller?

I googled around and could find no mention of a Primo-specific puller or any 25mm puller. The threads are curious; most cranks like this don't have them. Maybe there used to be a tool available for them, or maybe a hop-up kit with threaded-in caps.

These cranks are more or less Profile copies and as such, in lieu of any other recommended procedure or tool available, the implication is you remove them by taking a Profile crank tool, removing the sleeve from it (which is used during installation), removing one of the crank bolts and replacing it with the tool, and pounding on the end of the tool with a hammer to drive the spindle out of the crank splines.


How should I deal with bike messengers + others (salmon) riding the wrong way in a bike lane? Frustrated cyclist "jegrgic" poses this question at the New York Cycling Club (NYCC) website.

They say:

  When I see this, I want to just go over to the person and try to give them some common sense. But typically, I just do my best to avoid them (usually by going into traffic) and swear under my breath while shaking my head.

Is it productive to be confrontational in this situation? Has anybody been able to educate them? Should we let the salmon swim upstream unimpeded?

I want to just go over to the person and try to give them some common sense.

If I felt like that, I'd have to tell every second cyclist I see at night that they ought to have lights.

  Is it productive to be confrontational in this situation? Has anybody been able to educate them? Should we let the salmon swim upstream unimpeded?

Ring your bell. :-)


Are there standards for tubeless tires/rims? I still trying to understand tubeless systems (well, i understand the principal, but it's the implementation that I'm still confused)

In this video, they show a cross section of a wheel rim and tire.
I'm not certain if this is just a artistic representation of a tubeless tire and rim interface or one example for the Schwalbe tires ?

Are there consideration or things to look for when buying a tubeless tire so that I know will fit my tubeless ready rim ?

Schwalbe video

Basically at this point there's broad cross-compatibility in practice  among the tubeless compatible me-too type "systems" by way of everyone just copying each others bead and bead lock designs. A de facto tubeless standard emerged from all of it that more or less just works.

UST is an exception in that it's a clearly defined system in terms of the dimensions of both the rim, the bead, and other specifications like how the rim has to be airtight by itself. But UST has other issues, namely that for all the trouble one goes through to adhere to it, you get a heavier tire and no puncture-sealing if you run it without sealant, so it's pretty far out of favor. Using non-UST tubeless tires on UST rims and vice versa set up tubeless usually works fine, but requires sealant.


Would a IGH drive train last longer than a derailleur drive train? Would a single sprocket + 8 speed chain + single chain wheel used in combination with a IGH last longer than a 10 speed cassette + 10 speed chain + 3x chain wheels?

Image I have 2 bicycles.

Bike 1 has a IGH Rohloff Speedhub 14 with

16T sprocket,
40T chainwheel and
8 speed chain
using chain tensioner (the spring loaded one, not a tugnut). The chain tensioner is compulsory :)

Bike 2 has a

10 speed cassette (11T-36T),
3xchain wheels (40T,30T,22T) and
10 speed chain.

Both drive trains are used in the same conditions and maintained and cleaned at the same time and in the same manner.

Questions

Which drive train will last longer?
What influence does the chain tensioner in the IGH setup have?

In the IGH setup, the same sprocket and chainwheel are used for every ride.

In the 10 speed setup there are more cogs to choose from. The wear is spread out.

I think the 10 speed setup will last longer because there are more cogs.

A chain used in a single sprocket configuration should outlive a chain used in a derailleur system because it always runs straight between aligned chainring and sprocket.

A 1/8" single sprocket chain will last longer than a 3/32" derailleur chain because it has larger bearing surfaces between pins and bushings.

A cassette is likely to last longer than a single sprocket because wear is spread over multiple sprockets. Same applies for multiple chainrings on a crankset.


How to attach and mount wheels onto a cargo trailer? I am planning a bike to move heavy things, separate question here, and sixtyfootersdude is doing a cargo trailer that converges to some extent with my goal to move cargo here. I am not sure whether mounting a trailer wheel is the same as mounting a normal tire but bear with it I am trying to organize sixtyfootersdude's question at the same time as solving my own problem, just answer the question in the title thank you.

lantius is almost right IMO.

use a standard bicycle wheel with a thin through axle, supported from both sides. It's possible to make a really simple trailer this way that will carry quite a lot. The disadvantage is that it's wider than a single sided mount for the same track width (how far apart the contact patches are). Small wheels off kids bikes are often available cheaply or free, and will usually carry 50-100kg each for a few hundred km before they fall apart (come fail immediately, but they're free so don't worry about that).
use a single sided wheelchair hub. They are light and designed so the wheels are easily removable, which is handy for a trailer that will be packed away often. But they will not carry much weight (20-40kg each) because bike trailers get used much harder than wheelchairs do. They're also somewhat expensive unless you can find a stock of wrecked wheelchairs.
use a thick axle with single sided support. MTB hubs come in 15mm (Shimano) and 20mm through axle variants, and a 20mm steel bolt the right length is easy to weld onto the side of a trailer and will hold more weight than even a really well built wheel (you could even drill a 10mm hole through it to save weight. But it does need to be supported well as there is a lot of force on it). I have a trailer built that way that regularly takes 120kg or more without complaint. Unfortunately the build page for it is unfinished even though the trailer is ~3 years old. These 20" wheels are expensive($US135 each) because you will not find them second hand but they work. TriSled use those ones on their load bikes rated to over 100kg/wheel.

You will need to use small wheels on a two wheel trailer (or build your own hubs) because the side forces in corners are more than a 26" or bigger wheel can cope with. With a solid build and care when cornering a 24" wheel can work, but a 16" or 20" wheel will just work. If you build your own hubs with 100mm or more between flanges you could use bigger wheels, but you end up with a very wide wheel (you just added 100mm to the width of the trailer without adding to the load space).

Finally, you must look at Richard Guy Briggs' organ trailer. It's a bike trailer that carries a Hammond organ and player.


Missing piece from shifter I am missing the piece that holds the cable in the shifter body.  Does anybody know if I can buy just that part?  Are the treads standard and a could buy an inexpensive shifter and just take off this piece?

Yes you're missing a barrel adjuster.  There are two common threads, and its hard to tell which yours are in the photo.
If you have a shifter on the other side, it should have the same part in the right place.
Probably looks something like this:

and most bike shops should be able to order the part.


"Real" wheel diameter I have a 1983 Bianchi Bici 4, which I long ago converted into my errand bike, and the only one I'll lock up anywhere.
It's got 32C tires on it right now, but they only just barely fit in the frame with a bit of coaxing. The chain stays are about 3/16 away from the sidewalls, so I'm ok if the wheel is true. The problem is that the top of the tread is incredibly close to the bottom of the brake, as well as the clamp on the changer. Too close, in fact.

So, are there any 32C tires that will result in a slightly smaller overall wheel diameter when inflated? Montreal roads are notoriously bad, and I'd still like to use the fattest tires possible.

The bike was originally equipped with 23s, so clearances are very tight everywhere.

Thanks.

Even if someone had a magic database of actual versus nominal sizes for tires, they would need to know what tires you have now and their actual inflated size on your rims to answer.

The best answer is yes, probably there is a nominally 700x32 tire out there that's smaller inflated than what you've got. But, two issues there: tire manufacturers have gotten much, much better than they used to be about accuracy in size labeling, so finding that tire would now be a challenge. Secondly, manufacturers often correct badly size-labeled tires pretty readily, so even if there were a good recommendation out there, it would be a bad question for an SE site since it would be a product recommendation that's highly subject to change.

A better approach may be just get an accurately sized 700x30, which is an existent albeit not super common size.


CycleOps Mag Trainer skewer doesn't fit Can I use my CycleOps Mag Trainer without the skewer?

The skewer that came with my trainer does not fit properly. Does anyone know if I can use it with a Shimano Nexus 3/8" cap nut?

Many axle nuts for an internal gear hub will fit directly without modification. If yours does not, then there are options to fix that, similar to the set from Tacx below.

As with many issues with trainers, there is a solution available for this issue.

This is a set of accessories designed to fit most solid or thru axle bikes.  You would need to make sure that you get a set that correctly fits your bike.

Details of the accessory kit here.


Recommendation for tracking device I plan to buy a tracking watch/device and I'm looking for recommendations. Two key features that I can think of are

heart rate monitor
gps tracking

I think that Polar M400 provides these features, but I was hoping to get some educated advice.

I use a Garmin Forerunner 235 which has these features. The heart rate monitor is built into the back of the watch, rather than using a chest strap which I think the Polar model does.

It can also connect to bike speed/cadence sensors, your smart phone etc.

A dedicated bike computer like the Garmin Edge 810 is also useful as it adds a map display and route planning.


Will 40km E-Bike trip in Texel Island(Holland) be hard for untrained people? I'm planning to have a trip in Texel island(North-Holland) in April,

We are a group of 5 people, 22 years old, who know how to ride a bike

But we do not train on cycling.

Will a trip of 40km, in 8 hours+-, with an E-Bike be very hard for us?

Thank you very much.

Short answer: No you'll be fine and (if the weather allows) you'll have a wonderful day.

Longer answer: You are on an e-bike, 40km is about two hours of riding on an e-bike. This is independent of fitness, because you are on an e-bike. Saddlesoreness (is that a word?) might be an issue, but given that you have 8 hours total you can bike short bits with long breaks in between to rest your tender bits. If it turns out range is an issue you'll come across dozens of places where you can use those same six hours you have left to charge your batteries. Texel isn't crowded by dutch standards but it is by no means empty.

The highest point of Texel is 15.3m above sea level, the lowest point about 1m below, so hills are not an issue either.

More than your fitness level I expect the weather (rain and/or wind) might be an issue.


Perfectly round holes on new Schwalbe Pro One tire Two days ago I installed a new pair of Schwalbe Pro One Race Addix (tubeless setup) and went for a first ride yesterday. Today i saw that both tires had some (5 or 6) perfectly round little holes evenly distributed all around the tires tread which I didn't see when installing them. Are those holes meant to be there anf if so, what are they for? Or did I damage them on my first ride?

It is an increasingly common practice for manufacturers to add tire wear indicators, which are little divots like the ones on your tire. Otherwise, there is no objective measure of when to change a tire apart from your mileage log (and riders of different weights should be expected to wear out tires at different rates). Basically, once you can no longer see the holes, you should toss the tire.
Perhaps you already know this, but you can then rotate your front tire to the rear. One should not rotate tires as we do in cars, because our rear tires wear a lot faster. I always knew this in theory, but seeing this happen with the wear indicators really cemented the concept. In any case, you want the freshest rubber on the front for control. However, rotating a very lightly worn front tire to your rear wheel is perfectly fine.
In principle, this type of wear indicator could also be useful on rim brake rims. I have not seen them as often, however. The Pacenti SL23 rim definitely had them, but that was a bit of a niche rim. Otherwise, one has to estimate rim wear via calipers or by seeing if the brake track has become concave. The increasing adoption of disc brakes may mean that manufacturers won’t bother with these indicators, because disc rims don’t take wear per se.
Just in theory: what happens if you ride the tire after the wear indicators are gone? Remember that tires have a rubber tread, which is glued to a carcass made of rubber, cotton, or perhaps other materials I’m not aware of. (Illustration at Schwalbe tires.) If you wore off the tread entirely, you would now have either the puncture protection layer (if present; some racing tires may forego one) or the carcass itself in contact with the road. I am not an engineer. However, the carcass materials were designed to hold a shape, and not to contact tarmac. I would expect grip to go down substantially, and I would not expect the carcass to be durable in that manner. Once you wore out the carcass, you would presumably tear a hole in the tube. In any case, I don’t know how much tread is left once the holes are worn down. It could be possible to safely ride your rear tire once the wear indicators are gone, but not for long. Under no circumstances would I do this on the front tire.
Come to think of it, on the forums I used to frequent, I would sometimes hear about riders wearing their tires down to the threads. That was a reference to the threads of the tire carcass. Many higher end clinchers and tubulars in the 2000s had cotton carcasses, which could be very supple. Presumably (NB, I’m not an engineer) this was supposed to reduce energy loss due to hysteresis, which is a primary driver of tire rolling resistance.
Edit: Some time after I wrote the answer above, @A.Jahin asked a question where they posted a photo of a tire where the tread had been completely worn out in one spot. This, below, is an example of wearing the rubber tread out completely. You can see that the threads of the carcass have been worn.


How to guesstimate correct tire pressure in the winter? I ride a rather generic Merida hardtail mountainbike throughout the year. I don't own a pump with a gauge so I usually pump my tires at gas stations (that have automatic pumps with gauges).

The problem is the following: I pump the tubes outdoors, but the bike is stored indoors most of the time. Usually I just fill the tires so that they're a little bit softer than usual as to avoid having too high pressure after the air warms up indoors.

Is there a good method to guesstimate how much lower (in bar) the pressure should be related to the norm to accommodate for this change? Is this worth worrying about to begin with?

If it matters, the temperature difference between out- and indoors can easily be 35°C (~95°F; -20°C outside, +15°C inside).

Ideal Gas equation: pV=nRT

With +15oC and -20oC the pressure ratio between the two is: p1/p2 = (273+15)/(273-20). Or 13% higher pressure when put in the garage.

However that is assuming you are pumping it to maximum pressure, that the tyre can no longer (or very slightly) expand, making V (volume) constant.

That is the basics for your assumption. However, the tyre would flex and expand ever slightly. So, 5-10% would be good approximation to me, depending on how much you put into the tyre, and how big is your tyre.

Saving you all the calculation, I would suggest for

Road tyre : 700x18-24c, 85-90 psi at the gas station (less than 10% of the maximum pressure, but you need more traction if temperature is less than 0oC!!!)
MTB tyre: 26x1.2-1.5", 55-85 psi at gas station
MTB tyre 26x1.5"+, 20-42 psi
Hybrid/CX: 700x24 to 700x40, 45-85 psi.

Just a rough guide, but please make sure you check maximum tyre pressure, then subtract  10% ( just don't do bicycle stunt indoor...) Edit 2: This is for your maximum Cold-Tyre Pressure only. Your target should be within recommended (i.e. Cold-Tyre pressure at recommended pressure and make sure +10% and it should not exceed Maximum pressure).

So I believe the answer is 10% more of the recommended pressure would not do any harm if put in the garage (checking a few popular tyre in the shop)

=============================

EDIT: I have one tyre blown up when I put close to recommended maximum pressure, and let it exposed to the summer sun locking to the pole. It was the loudest bang I have ever heard.. and I would be extra careful from now and then when pumping an old tyre pass recommended pressure (leave alone the maximum recommended)


SRAM Rival brake caliper screws/bolts are rusty, how to replace? I have a full SRAM Rival groupset from 2011.  Having used it in humid and rainy places for a while, most of the parts are OK, but the small button-head screws (or bolts?) in the QR pivot for the brake calipers are quite rusty.  I guess the quality of these screws was somehow not up to the standard of the rest.

To be clear, I'm talking about a single screw per brake, whose head faces forward on the front brake, and backward on the rear brake.

Unfortunately, SRAM's maintenance guides do not call out these screws or dimension them in any way.  How can they be replaced?

I can answer this question myself, having removed the screws, measured them, ordered replacements, got the wrong size, and so on.  So other people can learn the easy way!

The screws (or bolts?) are M4x6 button-head.  The threaded portion is actually slightly longer than the nominal 6mm on my set, closer to 7mm.  But if you buy M4x8 screws you will find that they do not fit, because while the hole they thread into is plenty deep, it seems to be untapped beyond a certain depth.  So 7mm is the absolute maximum threaded length for these screws, and you should buy M4x6.  I chose titanium ones, but stainless would be fine too.

If you want to follow what I did, you should also see my follow-up question which describes how a tiny ball bearing will fly out of your brakes if you allow the QR mechanism to come apart when you remove the screw: What size is the tiny ball bearing used in SRAM brake caliper quick release detents?


Replacement brake pads for SRAM Force 1/CX 1 I'm looking to replace the default pads that come with the SRAM Force 1/CX 1. I can't tell if they're metallic or organic. I ended up purchasing the organic version https://www.competitivecyclist.com/sram-road-disc-brake-pads-organic, but they have a high pitch squeal. I cleaned the disc beforehand with isopropyl alcohol and bed in the pads on the first ride. If the original pads were metallic, would the rotors not be compatible with organic pads? The rotors still have ton of life in them, so just looking for a brake pad that works correctly, or any other fixes.

Should be OK, I have not heard of problems changing to different types.
Organics are normally quieter and less prone to squeal than metallic pads, in fact its one of their main advantages.

I would go though the normal steps for dealing with squealing brakes. Align the calipers, clean and bed in. As the pads are new, and you cleaned the rotors, I would align and see it if goes. If that does not work, very lightly surface the rotors and discs with fine emery paper and redo bedding in.

In some cases its just the  combination of pads, disk, brakes and frame don't work. If you can't live with it, changing to a different pad will often fix it.


What is the effect on battery life of enabling glonass support on garmin edge 25? I'm considering the purchase of a new GPS. The Garmin Edge 25 has most of the basic features I need. However, high accuracy is important to me as I do trail mapping for my local MTB club. I thought that getting a unit with GLONASS support would help improve accuracy, but I was concerned about runtime since the manual indicates it will reduce battery life.

What is the impact on battery life of enabling GLONASS support on the Garmin Edge 25?

You're only going to experience roughly a 10%, (maybe 20% max) loss of battery life. Unless you're planning on frequent century or all-day rides, the difference is relatively negligible. The average use case, a commute to and from work, or the average 4 hour group ride, won't see any difference because the battery life will go from about 8 hours on a full charge to 7 hours.

If you do plan to take it on century rides or night rides, you might want to upgrade to a medium tier unit, 510/520/etc, as the medium sized units have nearly twice the battery life. Using the GPS+GLONASS mode doesn't have a significant effect on battery life at all in this case because we're looking at about 16 hours of battery life in GPS-only mode vs 15 hours of battery life with GLONASS. Unless you're living on the edge (no pun intended), the GLONASS mode isn't going to make it or break it.


Shimano Tiagra Rear Derailleur - Barrel Adjuster Won't Screw In My rear derailleur barrel adjuster has unscrewed completely and now I can't get it back in.

Is it likely that I've damaged something here, or is there some special technique to screw in barrel adjusters that I don't know about!?

just in case someone else stumbles upon this while trying to solve a busted thread for the barrel adjuster, I managed to solve this yesterday by rethreading the aluminium derailleur housing gradually by going with smaller size thread screws first, then finishin with m5, that's the size of the barrel adjuster screw thread, which was in my case still intact. The problem was that a bike mech was lazy and didn't want to adjust the cable tension manually, so he/she unscrewed the barrel adjuster so far out of the derailleur, that it only held itself in place by 2/3 bends, in which case the leverage on those bends in case of an impact on the barrel adjuster is so great, that the soft aluminium thread inside the housing has no chance of withstanding that.


I'm going to take my bike with me on a plane. Do I really need a special bike travel bag to have it transported safely? I have a road bike that I want to bring with me to the place I will be flying to.

I know that there are bags that are designed especially for this kind of situation: the bike travel bags such as the one shown on the picture below.  But, as they are expensive (that one costs £250 for example) I would like to evaluate all the alternatives (if any) before I go ahead and spend so much money with something that I would use once in a blue moon. How could I prepare my bike to be taken on a flight if I don't own a bike travel bag?

I recently flew to Europe with my wife, and we brought along our bicycles. Our solution was to disassemble them the night before and place them into cheap Nashbar bicycle bags. We wrapped pipe insulation foam around just about everything to avoid damage from handling. For extra protection, we then stuffed these into the standard bike boxes provided (at a minimal cost) by the airline. I would highly recommend the internal bags, as the TSA opened both our boxes during each flight, and did not bother to close the boxes back up. Wheels or other components could have easily fallen out in flight had we not used canvas bags inside the larger boxes.

Also, be very careful about which airline you choose to fly on. Most airlines have a surcharge for checking bicycles, and this can vary wildly between carriers. Our tickets were initially on Delta, who wanted to charge us $200 per bicycle per leg. With a 2-leg trip to Amsterdam and back, this would have cost $1,600 to ferry our bikes, which was ridiculous. Thankfully, we discovered this within the 24-hour cancellation window and switched to Continental, who only charged $100 per bicycle per itinerary, costing us only $400.

At the end of the day, though, transporting your bike via airlines is expensive and annoying. Our next touring bikes will absolutely have S&S couplers to allow us to fit the bikes in regulation-size checked luggage, which should help us avoid airline surcharges and additional TSA inspections.

Good luck!