Correct BB axle length????

matt24777

Senior Retro Guru
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I've got a 97 Kona Cinder Cone fitted with some Shimano XT M737 cranks, and a Shimano XT M739 front Mech.

I'm having trouble getting the mech set up such that the cage/chain don't rub in at least 1 of the gears.

Now I'm wondering if my BB axle is too long and giving me a wide chainline, although it looks to be about 50mm.

What Axle length should I be using? :? :?:
 
It's got a 113 at the mo as I thought 113mm was the right one.

maybe I'll try a 110mm...

is this likely to be causing my front mech woes?
 
drystonepaul":1k76ifk7 said:
rider":1k76ifk7 said:
107-113mm
Exactly that. Although 113mm is the most common for those cranks.

Chainline should be closer to 47mm ideally.
No, the M737 should for most setups be using the 107mm length.

113 should only be used where 107 isn't working, e.g fat tyres causing problems, tubes, mech bands out at 34.9 (Even shimmed down).
I.e. 113 is only the optional length.

Still there shouldn't be to many problems.
 
FluffyChicken":ci33fl1o said:
113 should only be used where 107 isn't working, e.g fat tyres causing problems, tubes, mech bands out at 34.9 (Even shimmed down).
I.e. 113 is only the optional length.

Still there shouldn't be to many problems.

So 110 is not suitable?
 
matt24777":1pcnt473 said:
FluffyChicken":1pcnt473 said:
113 should only be used where 107 isn't working, e.g fat tyres causing problems, tubes, mech bands out at 34.9 (Even shimmed down).
I.e. 113 is only the optional length.

Still there shouldn't be to many problems.

So 110 is not suitable?

Technically you'll find out if bottom bracket length is your problem as it should be the same chainline as the 107 (on the Drive Side)
It will however leave the non drive side crank where it is (it only changes on one side)

Give it a a go.
The crank wasn't designed for the 110 (the M739 was for some reason which used a 110 not a 107)

Fit it and worry about being slightly to the left of centre later ;)

It could of course be something else, like just being a pain in the arse, funny chainrings/chain etc.
 
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