Hoping for some advice: bought some 2nd hand Middleburns about 6 months ago, and they've always had an irritating bit of play when shifting pressure from the front foot to the rear and back (i.e. landing hard vs. starting to crank and vice versa). I've tightened them to buggery trying to dial it out, to no avail. Chainring is on solidly, and I have just popped an old XT crankset on and have no issue, so nothing in the BB area either.
Any ideas before I sack them off and move on with my life?
Do you mean like a lose arm? If the arm has been removed and not installed properly this will cause issues as once lose it can move on the spline thus exaggerating wear. Send me an email at paul@betd.co.uk and I'll see if we can help as we manufacture Middleburn. Please send some pictures so I know which logo they are as that will age them for us.
Is there still the wave washer in place to take up the preload?
@Hadge, yes - like an ever-so-slightly loose arm that I can't tighten any further! Appreciate it, I'll drop you an email.
@Shedbrewed, they've got a threaded pre-load collar which takes up the slack on the NDS once the DS is cranked down, no wave washer though...
On RS8 there is a bearing preload collar you adjust, not the wavey washer. The wavey washers are used on RO2 X type cranks or tandem sets.
Measured the axle for roundness ? If they've been run on a BB with no plastic sleeve between the bearing and the axle, the axle is likely to be worn.
The Middleburn bottom brackets we supply now get shipped with bearings with a 24mm inner diameter as I do not like the plastic sleeve as it's prone to causing issues. Yes the axle could be an issue and it requires measuring to see if this is the problem.