's Forum Archives - Components

Archive Home >> Components(1 2 3 4 5 6 7 8 9 10 )

Dura Ace 7701 cranks and XTR bb?(4 posts)

Dura Ace 7701 cranks and XTR bb?crankrm
Oct 2, 2002 7:53 AM
Can I use an XTR bottom bracket with my Dura Ace cranks? They've got the same number of splines and it appears to fit when I put them together by hand (I haven't tried bolting them on yet.
Yup...Mike Prince
Oct 2, 2002 8:22 AM
Works fine, I use the same combo on my bike to address my chainline issues. I think its an M-952 cartridge BB. Just remember that your chainline will change with that BB vs the 109.5mm road double BB's.
what's the best way to determine which bb spindle length......crankrm
Oct 2, 2002 8:36 AM
I'm taking off an ultegra 600 double crank with the square taper, and I think that will have a different bb spindle length than what I need on the new Dura Ace double. I've got both the 112 and 116 mm xtr bb lengths.

I'm thinking that I'll measure the chainline to the big ring with the way it is now (ultegra 600s) and then install the 112 xtr and DA crank and measure that chainline to see how close I am. If I need more space, then I'll install the 116. Is there a better way to determine which one to use?

It's going on a steel frame if that makes any difference with chainstay clearances.
what's the best way to determine which bb spindle length......Lactate Junkie
Oct 2, 2002 9:51 AM
Buy a Dura Ace BB that matches the crank (109.5mm). You cannot draw any infernces from the Ultegra crank you took off. It used a longer BB becase the crank geometry required it to get the proper chain line, not the frame. If you use a XTR BB with a new DA crank your chain line will be off 2.5mm (maybe not too bad) to 6.5 (way off)