am8117

Some chranksets come with pedal washers, others do not, yet their interface with the pedal spindle looks the same.

Do I need to / should I use pedal washers with regular Shimano crankset and platform pedals that have spindle like the attached?

JohnDThompson 

The late Jobst Brandt felt that a washer between the pedal axle and crank arm could reduce fretting damage to the crank arm, which can lead to failure at the pedal eye. He did not think that a washer was an ideal solution to this issue, though, and modified cranks to have a conical seat for the pedal axle, similar to those used on automobile lug nuts. That modification would also eliminate the need for left-hand pedal threads on the left crank arm, but it's not a modification that can be done in the typical home workshop.

That said, pedal washers are inexpensive and IMO any reduction in fretting damage has to be a Good Thing. I fail to see a downside to using pedal washers, so I put them on all my pedals.

sweeks

But...but... the "Q" factor!

bboy314

With axles without rounded ends where they meet the crank (like the 1/2” pedal on the left), I think pedal washers are a good idea because these are more likely to gouge the crank arm when tightened.

pdlamb

I've only broken one crank at the pedal eye in a few decades. I think that was part of my "break everything on the bike" campaign, which is nearing completion. So no, I don't see the need for pedal washers.

msalvetti

Sorry, as a relative novice, I had to click in to find out why I needed to buy a device to wash my pedals.

Now I understand.

Mark

Litespud

I just installed an alloy Campagnolo crankset, and the instructions were adamant about not using pedal washers, because they “generate abnormal stresses in the interface area”. I honestly don’t see the point in washers, and with some pedals and cranks, I can see them reducing the amount of thread inserted into the crank, which is not good. And yes, a possibly-imperceptible but unnecessary increase in Q-factor. Sure, a steel pedal spindle might mar an alloy crank, but unless you never ride your bike outdoors, crank-marring is par for the course.

3alarmer 

.
...I use them routinely. They help to move my fat feet just a smidge farther out from the crank, and in many cases are the difference between the toe strap rubbing on the crank as the pedal rotates, and not. I have also not used them for many years before I started using them, and nothing bad happened to me.

Not sure why a Campagnolo crank set would be abnormally stressed by them, but suspect it has something to do with the construction of it. The mating surface of washer with crank and the mating surface of pedal shaft with crank is not all that different in area. But Campagnolo as a company has been telling me weird stuff for years...like their hand matched bearings stories.

am8117

This rang a bell, I started lacing wheels after getting his book, very no-nonsense and short read. Later I found the archives of the discussions that were going on in the - I believe it was USENET news - community with his contributions, very much to the point. I was totally unaware of this one of his, but it's totally like him, very simple solution no one is using.

NB I have also once cracked a crankarm at the eye, but it was steel and I was very young.

Lots of the time I have issues with recommendations coming from "manufacturers" without any decent explanation (i.e. it misses specificity as if on purpose), I can already see down this thread Campy made such one. I will now go search for that Jobst's crankarm eye contribution ... from days before Google.

And thanks!

am8117

I found that one now

https://www.campagnolo.com/media/fil...nolo_06_12.pdf

Looks like they do not make washers and whatever non-Campy would be causing injury or death. Seriously I would need to think hard in terms of physics why they might have said that. I do not think I *need* washers but I did not expect any source to tell me to stay away or else.

am8117

This is what I had thought and so added the specific spindle because I never noticed when it happened but it seems all current pedals come round like this at the eye contact point.

veganbikes

I see no harm in them so I would go for them especially for the crabons. Like JohnDThompson said they are cheap and only do good so not a bad thing. If you don't want to go for it, that is fine to but it is not a wallet killer and does a simple job just fine so no exciting reason to be totally against it if anyone actually is?!

am8117

I hope no one from Shimano Marketing Dept is reading this one.

am8117

I actually - maybe I was just oblivious before - noticed on an aluminium crank that the pedal eye area is a bit recessed. I do not remember anything like that from old fashioned cranks, so it got me thinking maybe they were trying to accommodate for an extra washer ... but then they had not included any either. I never used them before, ever, so I found the whole recessed circular area intriguing ...

veganbikes

Could very well be...I think a lot of folks don't include them because they would probably just get lost. Funny enough I have a whole baggie of them in my bedroom of all places. I always know where they are but I should probably put them in Big Blue or with my decently organized bike parts in one of the drawers.

bamboobike4

I lose them. Always.
Their value is that I don’t lose other, more important things.
Therefore, they are sacrificial.
One must manage most malady moments.

3alarmer 

...that's from the fretting mentioned above in reference to Jobst Brandt by JohnDThompson in post #2. It happens to all alloy cranks if you use them long enough without pedal washers.

skom25

There are not a lot things in bike, which are "cosmetics" only, especially if it is washer.

I heard that it is good or recommended to use them with Carbon cranks. I found also that LOOK pedals have quite long threads, so you can change Q factor without risk.

am8117

My bad, I was getting at the fact they might be there just to protect the anodizing or glossy paint i.e. avoid biting into the crank at that spot, but then - which is why I pictured the spindle - that interface was already as smooth and round as a washer.

I still can't get my head around the Campy's notice mentioned above though ...

delbiker1 

The interface between pedals and crank arms is not always the same. I usually just go by that. If the crank arm does not have a washer fit area, and the pedal snugs up into the threads with no gap at the stop area, no washer. For any pedal or crank set I have, no washer does not stop me from using them.

billridesbikes

Interesting. Campagnolo CF cranks have a warning not to use pedal washers. My guess being they have to make a bond between the carbon fiber and the aluminum threads and given maybe a pedal screw section that is too short and a washer a little too thick may put undue stress at that interface where it's only distributed part of the way through the crank instead of all the way as it's designed. Perhaps pedals with a long treaded section wouldn't apply here, but Campy doesn't know what pedal system is going to be used. Probably still a considerable margin of safety, especially for skinny old guys like me that have trouble hitting 1000W in a sprint.

Troul 

it's a wash...
If the crank has instructions on when to use them, I'll heed that written advice. Most often I look at the face of where the axle contacts the crank arm & determine on my own what to do.

FastJake

I always use them. They prevent stuck pedals and fretting damage. To me that is worth a couple grams and millimeter or two of q-factor. Good cranks are recessed for them...

Camilo

Yeah. How could a pedal washer be cosmetic? It's not visible!

I've only used them with CF crank arms - because they came with the crank arms. I don't recall any aluminum crank that came with them, nor do I think (without checking) that I have them on any of my aluminum cranks.

am8117

Nope, not that kind look here and I think any “R” FC has this look around the eyelet.

https://www.wiggle.co.uk/shimano-ult...speed-chainset