Bicycle Mechanics - Are pedal washers essential?

I got a Shimano Hone crankset and I either lost the pedal washers or none came with it. Are they essential or can I get by without them?

I note that the diagram for the M600 doesn't include the washers but the diagram for the M601 does include them, so if I am sure that I have the M600 I take it I don't need them?

Thanks for any help

I've never gotten pedal washers with any crank or pedal set including SR, Suguino, Sun Tour, Shimano and Campy cranks and Look, Wellgo, Shimano, Speedplay and several quill pedals.

I've never gotten pedal washers with any crank or pedal set including SR, Suguino, Sun Tour, Shimano and Campy cranks and Look, Wellgo, Shimano, Speedplay and several quill pedals.

+1, simply said; huh, pedal washers?

I've only gotten pedal washers with one crank -- an FSA cyclocross crank. I'll use them with that one but I've never used them otherwise.

But if you don't use pedal washers, you'll put ugly circles on your pretty pretty cranks!

Fsa cranks have the pedal countersunk into the arm. Without the washers and with certain pedal/crank/wrench combos the pedal flats sink into the crank far enough to pinch a wrench making tightening impossible.
I like em personally...
Lots of new bikes have them ziptied to one crank in a little bag.

But if you don't use pedal washers, you'll put ugly circles on your pretty pretty cranks!
Not only that, but the fretting damage from rotational precession can produce stress risers and eventually cracks and arm failure at the pedal eye.

http://pardo.net/pardo/bike/pic/fail/superrecordcrankcloseup-quarter.jpg

I thought only a few makes of crank were likely to do that. Campy, maybe neuvo record? I ought to check up on it, but most cranks are made of stronger stuff.

But if you don't use pedal washers, you'll put ugly circles on your pretty pretty cranks!

+1 And some types of threaded axle flanges of the pedals even gouge the alloy while tightening.

I really find it annoying when they do fall out and get lost... right up there in my top ten list of bicycle pet hates! When I have new cranks that come with washers, I always "super-glue" them on before the first pedal install.

For pricey cranks, you'd think those washers would've been pressed-in or glued-on at the factory. :notamused:

+1 And some types of threaded axle flanges of the pedals even gouge the alloy while tightening.

I really find it annoying when they do fall out and get lost... right up there in my top ten list of bicycle pet hates! When I have new cranks that come with washers, I always "super-glue" them on before the first pedal install.

For pricey cranks, you'd think those washers would've been pressed-in or glued-on at the factory. :notamused:
In order to work properly, they need to be able to spin freely.

My T.A. crank came with pedal washers. Harris Cyclery sells T.A. Pedal washers for $4.95 per pair.

maybe it isn't just older campy stuff...
http://pardo.net/pardo/bike/pic/fail/FAIL-001.html

Although pedal washers may not help
http://pardo.net/pardo/bike/pic/fail/FAIL-030.html

Damn that site is too engaging

Never heard of a pedal washer. Then again, I don't own a bike worth more than $200.

You see them on carbon cranks, and companies that want to make their stuff seem nicer (the only non carbon cranks I've seen them come with are crappy Bontrager cranks). They aren't a bad idea on aluminum cranks but are not mandatory.

In order to work properly, they need to be able to spin freely.
Huh? The washers don't spin at all. Gluing them in place would have no effect.

All I can see that pedal washers would do is give even pressure on the crank arm. It wouldn't seem that you really need to gorilla arm the pedals on the crank that much when installing them. Just make sure that they are snug. You pedal in the direction of the threads anyway so they wouldn't seem to unthread.

You pedal in the direction of the threads anyway so they wouldn't seem to unthread.

Actually this isn't the case as was demonstated to me this last weekend when my Candy-C's seized up on the spindle and unscrewed themselves twice before I could make it off the trail and back to my truck.:twitchy:

Actually this isn't the case as was demonstrated to me this last weekend when my Candy-C's seized up on the spindle and unscrewed themselves twice before I could make it off the trail and back to my truck.:twitchy:

you actually PEDAL in the reverse direction, BUT your bearings will invert the dierction of rolling resistance of the pedal to the crank. and the key here is you bearings seized. as you pedal your bearing roll in the reverse direction actually tightening the pedal.

you actually PEDAL in the reverse direction, BUT your bearings will invert the dierction of rolling resistance of the pedal to the crank. and the key here is you bearings seized. as you pedal your bearing roll in the reverse direction actually tightening the pedal.

I see what your saying about the bearings spinning opposite in relation to the spindle, but I would think that any "tightening" of the pedal would be offset by friction.

To the original question, whenever I put bikes together if pedal washers are supplied I use them, if not then don't sweat it.

I use pedal washers whenever installing pedals that have flats all the way to the crank arm. Most MKS pedals still use spindles llike that, and I'd rather not gouge up cranks if it's possible to avoid it. For FSA cranks with recessed pedal holes, even they say it doesn't matter for most pedals. Use them if you have them, don't sweat it if you don't.

The proper term is precession. It's the same phenomenon that allows bowl feeding machines to work. For those who don't know bowl feeders are machines that you can dump say, a bag of hex nuts into and the vibration of the machine will cause the nuts to move uphill along a spiral ramp on the outside of the bowl. They are then arranged in a uniform fashion for assembly line or assembly machine use.

From Sheldon Brown:
http://www.sheldonbrown.com/gloss_p.html

Pedal Threading

Direction
The right pedal has a normal thread, but the left pedal has a left (reverse) thread.

The reason for this is not obvious: The force from bearing friction would, in fact, tend to unscrew pedals threaded in this manner. The fact is, however, that it is not the bearing friction that makes pedals unscrew themselves, but a phenomenon called "precession".

You can demonstrate this to yourself by performing a simple experiment. Hold a pencil loosely in one fist, and move the end of it in a circle. You will see that the pencil, as it rubs against the inside of your fist, rotates in the opposite direction.

Ignorant people outside the bike industry sometimes make the astonishing discovery that the way it has been done for 100 years is "wrong." "Look at these fools, they go to the trouble of using a left thread on one pedal, then the bozos go and put the left thread on the wrong side! Shows that bicycle designers have no idea what they are doing..."

Another popular theory of armchair engineers is that the threads are done this way so that, if the pedal bearing locks up, the pedal will unscrew itself instead of breaking the rider's ankle.

The left threaded left pedal was not the result of armchair theorizing, it was a solution to a real problem: people's left pedals kept unscrewing! I have read that this was invented by the Wright brothers, but I am not sure of this.

Note! The precession effect doesn't substitute for screwing your pedals in good and tight. It is very important to do so. The threads (like virtually all threads on a bicycle) should be lubricated with grease, or at least with oil.

Here is a great video of a bowl feeder. They're pretty cool so if you haven't seen one you should really watch this. Note that the machine has no belts, it is just vibrating in the proper pattern.
http://www.youtube.com/watch?v=fxQFbYegKf8

Precession has nothing to do with the crankarm failure pictured. If a pedal comes loose for some reason, the wrong threading direction would help it unscrew. The forces of precession do not cause a pedal or bottom bracket cup to unscrew, it merely speeds up the process of unscrewing.

If precession forces were actually as large as some people think, then you could lightly tighten BB cups or pedals and they would tighten themselves with use. That is NOT the case.

Italian BBs are the perfect example. While the right cup might unscrew if it ever came loose, but it won't loosen just because the right side has right hand threads. I've ridden Italian frames for year and never had a BB cup come loose.

In the process of building several recumbents, test fixtures, and so on with college projects I've seen several where new people put the bottom bracket in backwards accidentally, and several where the cranks were put in backwards to get the chain to the left and therefore out of the way of something else. When the threads are clean it's fine and if you torque it down sufficiently precession shouldn't cause your pedals to come out. However, if the threads are worn down or the pedal/cup is not torqued down enough, it will make them come out. At some point if the threads are worn enough it's almost impossible to not precess out.

Also, unlike some above I'm not trying to blame the crank arm fatigue failure on precession, I'm just stating why the left pedal and right BB cup are left hand thread.

I just had the experience of the threads stripping out on a FSA crank arm with no washers. I was told that without the washers you cant get the pedal tight enough because the wrench gets pinched before they tighten completely. Bike shop guy's words not mine. It was my first complete build and I never had never heard of pedal washers. Luckily it happened within two days of riding so they are sending me a new arm.

I've gone with and without.
If you're only gonna run these cranks for say 3 years or so and not remove/replace pedals often then it doesn't really matter.
Things get ugly over long term use without washers in my experience.

^ RE: LBS story up there. That dude is telling a story. He should have a wrench that won't get bound between pedal and crank be there a washer or no.