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Deyv
07-22-2003, 09:35 AM
I replaced my 116 mm XTR BB with the only one that was available with the LX crank on Jensonusa.com.

Jenson was mentioning that you can only fit the es51 121 mm BB with the LX crank I bought.

But with the 121 mm spindle my front shifting is horrible and the chain line is causing mucho friction.

Was I deceived by Jenson, should I run a more standard 115 or 118 BB?

Thanks
Deyv
07-22-2003, 10:53 AM
Originally posted by Deyv
I replaced my 116 mm XTR BB with the only one that was available with the LX crank on Jensonusa.com.

Jenson was mentioning that you can only fit the es51 121 mm BB with the LX crank I bought.

But with the 121 mm spindle my front shifting is horrible and the chain line is causing mucho friction.

Was I deceived by Jenson, should I run a more standard 115 or 118 BB?

Thanks

Ok, I just talked to the LBS and they confirmed that with the new LX crank (572) you need the 121 mm BB.

Now I need to find out why I feel this much friction will pedalling.

I feel like I am talking to myself but it might be usefull for someone else.

babling done
BikeGeek
07-22-2003, 11:11 AM
Weird. I couldn't find any tech manuals at Shimano for the 572 crank. 121 does seem to be really long though.
sub6
07-22-2003, 11:25 AM
the new LX have really deep splines, so the arm sits far down on the spindle, hence the need for long spindle.

Are you sure it's an '03 LX crank? If it's an '02, then it'll be way too far out....
Deyv
07-22-2003, 12:29 PM
Originally posted by sub6
the new LX have really deep splines, so the arm sits far down on the spindle, hence the need for long spindle.

Are you sure it's an '03 LX crank? If it's an '02, then it'll be way too far out....

I bought them together from Jenson and it was specified M572 with 121 mm BB only but maybe they shiped the wrong one, I need to check.
Squeak
07-22-2003, 12:48 PM
You sure your frame is ok????
ohio
07-22-2003, 01:50 PM
Originally posted by Deyv
I bought them together from Jenson and it was specified M572 with 121 mm BB only but maybe they shiped the wrong one, I need to check.

Does it have a big bulge in the middle, or is it about the same width from spindle to pedal?

Big bulge = M572
Deyv
07-23-2003, 08:18 AM
Update:

I checked and I have the proper Crank (M572) and the chainline is good at 47.5 mm with the 121 mm BB.

The friction I was feeling comes from a slightly used chain on new rings and casette, after 10 minutes of riding it was smoother.

Thanks for your help.

This was my first major operation on a bike and I am pretty proud.