Q factor and short cranks

I have fitted some Prowheel 102 mm cranks to my 700c. previously, I was using cheap steel 102s.

The new cranks are lighter, but have a slight double bend which places the pedal slightly further out from the central plane of the wheel.

The wheel now shows much more side to side wobble at speed.

Am I right in thinking that the angle of the force, relative to the plane of the wheel is important - as well as the actual distance from the centre of the plane. If so, this means that the same amount of offset in short cranks has a bigger effect on short cranks than on long ones.

I’ll keep practising, but I’ve done a lot of miles on the 700c recently and this speed wobble is definitely worse than it was.

Anyone know any reasonably priced straight 102 mm alloy cranks for square tapers?

I have Bike Euro 110mms on my 20". They don’t have any ‘Q’ on the go that I can tell. They didn’t fit too well on my UDC CrMo hub though. Qu-Ax sells 102s or equivalent I think, and those appear to fit much better. UDC should have something along the lines of what you’re looking for in any case.

I’ve just fitted some Prowheel 102 mm cranks to my 20” because 1. I kept whacking my ankles on the cranks and 2. I kept hitting the peddles on the floor with tight turns.

I’m hoping that because these are shorter than my last cranks (110mm) and with the Q factor of these they’ll help. Unfortunately the hockey we played at the Scarborough unicycle and circus convention yesterday was on sandy astro turf which you cannot make tight turns on, well if you want to stay on that is, so I couldn’t try them out much.

As for wheel wobble, this I noticed immediately and that’s with them on a 20” so it ought to be worse on your 700c. I’m getting used to them a bit though I can’t get up to speed, not yet at least, but Roland has had some for a while now and he can wiz around so they do work on a 20”.

If they don’t work out on your 700c you could always pop them on your 20” for when you come to hockey. :slight_smile: