Widening q factor with pedal washers?

[bludger]

I think my Shimano M520 pedals are a little too close together on the road bike to fit me comfortably, which makes me press down with the outside of the feet a bit much. I thought I might use some thing washers on the pedal axles to widen them apart a bit before investigating things like insoles, or new pedals altogether.

The cleats on my shoes are already as far out/in as they can be.

Any insights on using washers e.g. recommended dimensions and what amount of pedal axle is safe to not have threaded into the crank would be appreciated. I've had someone knowledgeable about bikes tell me cranks only need about 13mm of axle inside of them for the pedal to be safe but would prefer some written down info if it's available!

[robgul]

Have to say I wouldn't put a spacer/washer in more than about 2mm - there's quite a lot of pressure on the pedal threads in the crank arms.

For reasons related to an issue with one of my feet/ankles I needed to increase the Q-factor and have been using these  https://www.ebay.co.uk/itm/1-pair-titaniumbike-pedal-extenders-bicycle-pedal-spacers-for-bicycle-ped-DIUK/264269341461?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649  - quite a big jump in width but they work for me - I have them on 3 of my bikes, all with Tiagra cranksets and SPD 520 or 530 pedals - with no discernible flex etc.

Rob

[Brucey]

I'd broadly echo what is said in the post above.  I'd also note that folk who have wider than average feet probably need pedal extenders with shimano SPD pedals, if they are to keep the cleat centred under the middle of the foot.

cheers

[Kim]

What do the quick-release pedal (Wellgo QRD, MKS EZY) systems do to the Q-factor?  Might be a useful middle ground between washers and extenders...

[Brucey]

What do the quick-release pedal (Wellgo QRD, MKS EZY) systems do to the Q-factor?  Might be a useful middle ground between washers and extenders...

I think the Q is usually increased slightly when pedal models are adapted to be EZY type



but I don't know if this is by a consistent amount or it if is well documented.

cheers

[Paul]

Is there a good reason for not looking at a wider bottom bracket?
You might have to adjust the front mech, but it could be an option.

[bludger]

Thanks chaps have just bought a set of those doohickies. They should arrive in a week or so. I'll give them a go on the big boy bike I do audaxes on, might have to get another set for the town bike if they necessitate adjusting the cleats. Though the pedals on the town bike seem a bit wider in q factor anyway 💁‍♂️

[Kim]

What do the quick-release pedal (Wellgo QRD, MKS EZY) systems do to the Q-factor?  Might be a useful middle ground between washers and extenders...

I think the Q is usually increased slightly when pedal models are adapted to be EZY type



but I don't know if this is by a consistent amount or it if is well documented.

cheers

I'm thinking of the QRD clipless models, where there has to be enough room for the shoe not to foul the release lever as the crank rotates.  Not sure if that means a socket's width of extra Q-factor, or just a more restrictive range of shoe sizes / cleat positions compared to the normal equivalents.  I'll have a go at measuring the ones on my Brompton later...

[The French Tandem]

What sort of bottom bracket do you have? Some bottom brackets can be made up to 3 or 5 mm wider by using special washers. If you have a square taper BB, just swap for one with a longer axle!

A

[bludger]

Shimano RS500. My reservation would be that I'm not 100% sure what adjustment is needed so I'd rather fettle the more accessible cleat/pedal placement than mess around with BBs. Though I appreciate a BB adjustment may be a more robust solution...

[grams]

That’s a Hollowtech II BB. He problem is the axle is a fixed length (because it’s part of the right crank), so if you try to widen it the less spline length the left side has to clamp on to. It’s doable - my Brompton is slightly over width to clear the chain stays - but only a couple of mm tops.

[The French Tandem]

Agreed!  Hollowtech II have rather flimsy splines, so maybe you can extend the Q factor by 1 or 2 mm, but not more. If you add a 1 mm washer on each pedal, that gives you 4 extra mm overall! Not sure you can get much more than that. Another (more costly) solution would be to change for a square taper chainset, which would let you choose a BB with as long an axle as you wish.

[tatanab]

solution would be to change for a square taper chainset, which would let you choose a BB with as long an axle as you wish.

At risk of upsetting your chainline which some  people and/or cycle parts seem very sensitive to these days.

[The French Tandem]

Honestly, I don't understand what's the point with chainline on a multiple geared* bike, and why do some people seem so sensitive like you said! On an 11 speed cassette, at best one of the sprockets will have a perfect chainline, the 10 other sprockets will be off by up to 20 mm, so can we really imagine that 1 or 2 extra millimeters on the bottom bracket will change anything?



*: Okay, on a single speed, it's another story.


Edit: I assumed you have only one chainring. With 2 or 3 chainrings, the problem gets even worse!

[mzjo]

Returning to OP, in the dim and distant past TA used to insist that their cranks be mounted with a steel washer between pedal and crank. I don't know if they still do. They used to sell a special washer just for the purpose.

[Brucey]

re chainline; of course it matters. It matters from the POV of wear, efficiency and (of course) front shifting.  Modern FD's only work (index)  properly over a rather small range of chainlines, so adjusting the chainline on a system that is working properly carries a fair risk that the system will immediately be converted into the other (i.e. non-working) sort.

cheers

[bludger]

I've now done some road testing of the titanium extenders. The results are very good. No ankle or etc pains after the 320 km london orbital at all. I am a little concerned after people have told me that ti stuff is liable to snap but until that happens I'll be a happy man.

It has also made the bike feel a lot more stable on big descents, and made trackstanding at the lights easier! I'll be interested in seeing what the effect is in cyclocross next Thursday. It *may* make pedal strike slightly more likely while turning. We'll see.

[robgul]

I've now done some road testing of the titanium extenders. The results are very good. No ankle or etc pains after the 320 km london orbital at all. I am a little concerned after people have told me that ti stuff is liable to snap but until that happens I'll be a happy man.

It has also made the bike feel a lot more stable on big descents, and made trackstanding at the lights easier! I'll be interested in seeing what the effect is in cyclocross next Thursday. It *may* make pedal strike slightly more likely while turning. We'll see.

I now have titanium extenders on my two Van Nic machines and the Orbea Gain e-roadbike/tourer - and the steel version (bought in error!) on my ancient 1975 Galaxy - the riding position has helped with the issue with my left ankle/foot where (the diagnosis so far) is the the tendon on the inside of my left ankle is stretched and not holding the foot under the end of my leg properly ... the foot is veering to the left at the bottom of my leg!    What's odd is that riding the bike is pain-free - but walking is frequently excruciatingly painful

Have to say I'd be surprised if they did break ... all my riding is sitting down as the ankle prevents me from honking out of the saddle, so less stress on the pedal axle and extender.

Rob