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My wife's got this Trek, and the BB on it is huge - 122mm I think - and it's far too wide there's at least 8mm bare axle showing on each side and since I'm trying to use it for Zwift it's like pedalling an exercise bike at the gym.
I roughly measured the shell and it looks like 70mm - could it possibly be an Italian thread or is it really 68mm? Italian is pretty niche isn't it?
It's only too wide if the chainlike is out, 122 is a common length on low end non compact triple.
I can't imagine it's 70mm or Italian I'm afraid. Sorry!
What cynic-al said
It'll be 68mm, noway have trek used Italian fitting.
No problem running a shorter BB, if the axle is that far out and you Def have clearance for the chainring and arms. It might mess the chainline a tiny bit.
Don't forget when measuring a replacement BB that the difference in axle length is mostly drive side only.
It’s only too wide if the chainlike is out,
Or if the pedals feel really far apart and it pisses me off.
There is about 8mm axle showing on the drive side and 10 on the NDS.
Sounds like you need a new chainset and BB.
Please don't ever try a fat bike ☺️
Don’t forget when measuring a replacement BB that the difference in axle length is mostly drive side only.
No it isnt
I had a Trek MTB of similar vintage and it was a 73mm BB shell. Worth measuring again.
I'm gonna stick a HT2 BB on it and some road cranks I have in the spare bin.
If they fit at least you will know it’s definitely a 68mm English threaded shell.
I only found out recently that road cranks don’t fit mtbs with 73mm shells. Even after persuading with the big hammer...😂