Getting fed up with my pinch bolt style HT2 cranks. I fit them correctly but after a few thousand kms they get a wobble on and then i have to start fixing them mid-ride (see TOTW on faffing). I'm guessing that both my XT and XTR sets now have knackered splines 🙁
What are the good alternatives? Criteria are:
-24mm as i don't want to replace 2 x Hope BB as well
- reasonable priced chainrings
- preferably no special tools
XTR M9100/9120 cranks don’t have the pinch bolt design - nor do the old M970s.
Got M9120 on one bike, but I prefer the pinch bolt style though. Only ever had one issue which was my fault, despite having over a dozen sets since they first came out.
Sure your torque wrench is still calibrated correctly?
I fit them correctly
Maybe not, something's not right if they're loosening after just a few 1000kms. It's the most solid crank-axle design out there imo. Might be correct fitting of the LH crank but something else not right before that stage.
Do you right left foot forward? Check the bolts after a couple of rides?
Correct number of spacers in there for the BB shell width, correct BB cups?
Race Face affect or the cheaper ride will fit those 24mm BBs.
-24mm as i don’t want to replace 2 x Hope BB as well
See, there's your problem. Run Shimano BBs and you'll need to replace the BB before the crank works loose, so those Hope's are costing you extra for the BB then extra for new cranks - false economy?
(slightly tongue in cheek as new XT BBs seem to last well).
Several sets of middleburns have been entirely trouble free for me for years now.
Saying that, pinch bolt style XT and Deore have also been faultless.
Perhaps a bit of extra loctite, if it's not already too late?
Do you right left foot forward?
Ha.. I need coffee. 'Ride right foot forward' is what I meant - if so you land on the LH crank levering it one way vs the axle, then pedal hard levering it the other way. Can mean LH cranks come looser easier, was more a thing with square tapers though.
SRAM GXP carbon cranks have served me well, very light and very easy to install - no pinch bolts required. You'd need to purchase the GXP shims for the Hope BB, I believe they're only a few quid though.
Ok… have meticulously cleaned and refitted the xtr 9000 for one last chance. Will ride the 8000 commuting tomorrow.
The calibration of the torque wrench isn’t guaranteed.
I am right foot forward.
I do break most things I come into contact with too.
No eeWings for me yet.
Might be worth doing a wee check of the bolts every half dozen or so rides, just to make sure they aren't working loose. If so, maybe a wee touch of loctite on them?
Why don't you just 'tweak' them every 500 miles instead of waiting till they fail mid-ride ? I mean, it's 2 bolts... it's about 3 minutes once a month or two..
My understanding is once its worked loose and been ridden on the splines are shot and it will never again be secure
Personally I much prefer the race face design.
Fair enough @weeksy I’ll add it my pre-ride fafflist.
I’ve knackered splines before and I’ve also had sets that will go back together nicely … for a while.
I've always had this with Shimano cranks - must be user error!
Switched to RF Aeffect and ne ver had a problem since