Just changed the main bearings and now freewheeling my hand the hub sounds quite metallic.
This is a boost six bolt microspline hub. I think j-bend but that's the one thing i would need to double check.
I've checked the order of bits and happy it's correct ie. From inside out
Bearing 6902
Shim ring
Axle spacer
Ratchet ring
Seal (rubber out)
Spring (wide end against bearing)
Star ratchet x2
Spring
Freehub wide end on bearing
End cap
My other 350 hub has a different looking freehub and the other other set are 240 Ratchet Exp so can't really compare.
The only thing I can think of is the ratchet ring is back to front, but it's in the most logical orientation (teeth flush to outside rather that recessed teeth) but maybe that's the problem?
Lack of lube/grease?
Presumably you cleaned and regreased the ratchets with the correct DTSwiss grease applying a very small amount of it as per the recommendation? If so then the noise will be normal. 240s are a bit noisier than the 350/70s. 180s are noisier still..
Yes. Its now not really wanting to freewheel when on the bike (in the smallest cassette sprockets especially) so suspect maybe too much grease. Tomorrows project now 😂
You should be able to compare to the 350. 240 non exp and 350 are the same. there is a lightweight freehub version but that is mainly lighter smaller bearings. Ratchet ring has a recess for the shim, that should face the bearing.
I think the shim has been damaged slightly, but not certain that's the issue. I've had it apart many times this evening, happy it's all together in the right order. The bearings seem to be sensitive to be being pressed in just right, I suspect I will pass this onto the shop as I'm not making any progress currently.
I'll try do photos of each freehub, I suspect there has been a revision at some stage. I'm pretty certain it's the original for the hub but you never know, it might have been mixed up!
The freehub difference is all about weight. The smaller bearing version is about 10-15g lighter. It normal Chinese with the hollowed out ratchet rings which are also lighter. Downside is the bearing life is less. The normal and light versions are mix and match. Using the lighter one and the hollow ratchets you can get a straight pull 350 to pretty much straight pull 240 weight!
Yeah the shim is easy to damage or for it to slip and not be central meaning the ratchet ring will not go in fully.
If you don't have them already I'd recommend a bearing press and over axle drifts. Much easier to get the bearings in straight. Also if you are going to DIY your exp hubs it's a different ratchet tool and you really need a press for the bearing inside the ratchet ring for removal ands replacement.
