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Mega 290 2022
Trying to solve a creak when put power through pedals. Had probably run the pivots a bit loose for a few rides.
Did a full bearing replacement. Some were a bit grindy but nothing terrible. None of the bolts/main pivot axle looked worn (they had no patches where coating had worn off). But still seem to have some movement in both main pivot and at top of seat stays. If the parts don’t seem worn I don’t get where it can be coming from
is it normal to have a little movement?
And the creak is still there. Wondering about cranks or bb now but those bearings are sound and there definitely never been loose.
Any ideas?
No. Definitely shouldn't be any noticeable play/movement other than rotational movement at any pivot
Are you sure you definitely seated the new bearings fully? (they can be quite awkward, especially the linkage bearings because of that links' angular design) and are you also sure you replaced each of the spacers from behind each bearing at each pivot? and also orientated them correctly towards the bearings.
if you've run it with play for a while you may have worn bearing seats/pivot hardware/frame bores but unlikely if it was really only a couple of rides
Everything Gaah said. Definitely should be no play after a bearing change. If there is then definitely something is wrong, never mind the creak.
My Mega 290 had a creak I traced to the shock eyelet bearing (these were fitted to Fox X2 air shock builds I think). Just removed and replaced with normal eyelet bushing and it was silent.
So I'm thinking there are two possible issues. Theres the creak/crack that comes when pressure is put on the pedals. If I put pressure on alternate pedals with the bike stationary theres a 'crack that you can sense through the pedals. (the pedals themselves are fine). theres no movement in the cranks.
Shock bearings have only had a week of riding (DHX failed and I fitted a Vivid Coil).
On the bearings I had no parts left over. I was thinking I could possibly have swapped the caps from the main pivot with those on the lower shock pivot as they're the same size bearings but I've just remembered I refitted the shock linkage to the bike before I started working on the main pivot. None of the bearings were loose in their seats when I removed them and none of the hardware had worn through the coatings so even though they might not have been properly torqued they weren't moving significantly.
Front shock linkage - is there a right way around for part 28? I've got a little scallop showing in front of the bolt on the outside and that doesn't look massively tight in its hole. (but it's a clamping action so shouldn't matter if it's tight)
(these are the only images I can find now as the nukeproof site is down - from manuals.lib)
Deal with the glaringly obvious issue first. Ie. Figure out why you have play in the main pivot and the seatstay linkage.You shouldn't have ridden it at all until rebuilt with no play.
I'm still thinking you've either not seated those bearings fully or have the spacers fitted incorrectly (possibly both). It's quite a simple design but getting the bearings seated fully isn't quite so straightforward. Especially those extended inner race/lipped outer race swing link bearings.
You haven't mentioned how or what you used to seat the bearings. A standard bearing press won't seat them fully as the extended race bottoms out on the tool. .
Once you've removed the frame pivot play test the frame for creaks with the chainset removed completely. (also giving you the opertunity to check BB bearing condition separately)
@gaah - thanks. I think it's sorted. non-drive BB. I couldn't feel any play in it and the drive side was tight, but my shimano BBT9 tool wouldn't go round the non drive (had to dig out my Icetoolz one which was in the car kit not workshop when I did the bearings). the mechanic at BikeParkWales had been so condescending about my idea that the issue might be BB rather than bearings I've probably replaced a load that would have been fine for ages and didn't properly check the BB.
Deal with the glaringly obvious issue first. Ie. Figure out why you have play in the main pivot and the seatstay linkage.You shouldn't have ridden it at all until rebuilt with no play.
I'm now not convinced there is any play. Someone else felt it and said there was but I'm now pretty sure it's rotational.
quite a simple design but getting the bearings seated fully isn't quite so straightforward. Especially those extended inner race/lipped outer race swing link bearings.
You haven't mentioned how or what you used to seat the bearings. A standard bearing press won't seat them fully as the extended race bottoms out on the tool. .
The extended race faces inward so they press blind the same as any other bearing. I didn't have the specific tool (I'd ordered the tool from BearingProTools but it still hasn't arrived a 12 days after they shipped first class) but did it with the flat side of another press and a hollow 'extraction' piece from one of their wind out pullers on the backside against the linkage.
Glad you're sorted. If it's the original BB. Lots of Nukeproofs arrived in shops/CRC with one BB cup that wasnt tightened enough from the factory. (Guessing they had a weak assembly employee for a few batches ) Hopefully it'll stay tight now you've torqued it properly.
I've got the exploded diagrams as proper files, if you need them I can send via email.
no, frame only. Built by me. And I’ve a torque wrench that I would normally have used.
threads don’t look bad but the grease was dirty (was clean on the other cup) so there has been some movement. It wasn’t loose, just not fully torqued