Oso Polar

Hi!

Probably something extremely stupid and trivial but new to me... Removed the wheel, changed cassette, tried to put it back and discovered that it doesn't fit because axle is suddenly too long (and moves side to side a bit). Apparently some nut became loose - so loose that I removed it completely with my bare fingers, see the photo.



Now, what it is and how to fix it? How to properly tighten it back, what tools, what torque? I can put it back finger tight and insert the wheel back, it seems fine but...

tFUnK

Put it back on, just tight enough that there's no play but not so tight that the wheel rotation feels binded.

Andrew R Stewart 

It looks to be either a bearing cone lock nut or a bearing retaining nut, depending on the bearing type and the axle design. Some bearing types need this nut to be specifically located WRT the bearing preload. Some designs are not subject to how tight this nut gets. Do you know which bearing type your hub has? (I suspect it's a cartridge type, not a cup and cone). Can you remove the rotor to see if there's additional wrench fittings on other axle parts (indicating a possible cup and cone type). Andy

Oso Polar

This is the stock 2018 Jamis Renegade Escapade wheel, bike specs say: "Formula alloy Centerlock sealed bearing hubs with front 12mm/rear 12x142 thru-axle".
Photos with rotor removed (and this unknown nut attached):

dsaul

Its the thru axle end cap. There should be a corresponding end cap on the other side with wrench flats. If it has sealed bearings, you can just tighten it by using a wrench on both end caps. Tight enough to keep it from coming loose is all that matters.

fietsbob

Through axle wheel hub, but the wrong lockring on the centerlock style disc hub? they use a ring wrench and external lockring splines..

Oso Polar

Did this and so far, so good, looks like everything is back to normal! Thank you and everyone else for the help!