I need a 68x110 BB for my 957, ok now what?

[David Cepp]

I cannot find a 68x110 BB with a splined surface. I am looking to upgrade my 957 with a new BB and crankset with an LX model or similar. I know there are many of you that have a 68x110 BB size, so what BB and crankset are you using and any idea where I can purchase a crank and BB?

I have found a square type 68x110 BB, but what model crankset can I purchase new for this BB.

Again, I would rather have a splined BB.
-Dave

[Sprucey]

Hi David,

I thought the shell was 73mm on Proflex bikes? It is on my Oz anyway and I can't remember what was in the 857 but I think 73mm also? Its 73mm on my Razorback Team 03 as well.

As for axle length, that depends on the crankset you are going to fit.

113mm or 118mm should do it as standard for most cranksets. As a rule of thumb, 113mm for full suss and 118 for hardtail. When using XT I use 113mm on most bikes. Maybe 118mm on DH style bikes with only one or two chain rings (gies more room for chain devices etc.)

Please note that 2003 LX and later uses a special, extra long, 121/122 bottom bracket - it wil not work on a shorter axle length as the crankset hits the BB shell otherwise.

The only reason to go to 110mm is to straighten the chain line and narrow the Q factor (distance between pedals). Somepeople think the chain line is better with shorter axles but you must be careful that the inside of the crank arm does not touch the chain stays if you go short.

I hope this helps?

Sprucey

[Sprucey]

p.s - Shimano don't do anything shorter than 113mm in Octalink splined.

Sprucey

[Dave]

PS-I found out on MTBR.com that the ES-51 68x121 size BB will work on the 68x110 square taper BB bikes for the M572 LX cranks. Off to JensonUSA I go!
-Dave

[kiwi]

Bottom Bracket Shimano BB-UN51, 110 mm spindle BB Shell Width 68mm English      

756...w c frames must all use 68 x110