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Managed to lose mid ride the little plastic fixing bolt off my cranks, resulting in my drive side crank working loose, I’m guessing it hadn’t been adequately torqued by the bike shop (or checked by the rider!).
Going to order a replacement but thinking of getting the Burgtec one as it’s an 8mm Allen key to nip it up rather than that oddball crank tool thingy.
Loads of previous XT cranks listed as compatible on the Burgtec website but not the M8100, does anyone know if anything has changed from previous versions?
https://burgtec.co.uk/product/shimano-crank-bolt/?v=79cba1185463
TIA
I’m guessing it hadn’t been adequately torqued by the bike shop (or checked by the rider!)
That part doesn't hold your crank arm on, the pinch bolts do.
The fixing screw isn't listed as being compatible with any other cranks in the Shimano tech docs but I haven't got one in front of me to see if it is unusual.
Isn't the purpose of that 'little plastic fixing bolt' purely to preload the bearings? While the cranks are held in place by the two M6 bolts on the non-drive crank arm?
Too slow!!
but if the pinch bolts are loose the fixing bolt disappears somewhere on a ride and you spend a while trying to fix your cleat before realising its the crank arm.
Having a quick look on Merlin/SJS and there seems to be a different version for the latest road crank sets bit the MTB ones seem to be similar
When doing a trail side fix it seemed that without it, it wasn’t possible to get the splines protruding sufficiently and that the drive side crank wasn’t sitting fully on the splines and that as a result the outside pinch bolt wasn’t biting. I was thinking that the plastic bolt would pull it through fully. Sounds like that’s not the case?
I recommend the alloy kcnc ones from clee cycles, half the price of Burgtec, they use the shimano tool instead of an allen key, I'd rather use the plastic shimano tool so you don't overtighten.
Though I didn't think those preloaders could come undone once the pinch bolts are done up correctly. Somebody fudged up.