Crank rubbing against bike

boudreaux

This is not rocket science.Your crank uses BB ES71 in either a 113 or 118 spindle length. Your only other choices are dependent on shell width; 68,70(italian threaad) or 73mm. Measure it.

Hecubus

That is precisely the problem the M572 LX cranks DON'T use a 113mm BB! The ES-71 is for the new 752 XT cranks only! The 572 LX cranks have a much deeper bore than the previous 570 and 571's requiring a longer spindle on both side and particularly the drive side. The 572's REQUIRE the ES-51 BB and no other. These ES-51's come in 121mm or 126mm. That's the problem. He was sold the wrong BB and crank combo. Even the 118mm ES-71 is too short. The crank is hitting the frame long before it bottoms out because the spindle is way too short. Shimano's decided to use specific BB's for each group now. No longer is it like the older splined 750/751, 570/571 cranks which all could use either the ES50 or ES70 BB. Now the 752's require the ES-71 and the 572's require the ES-51. The ES-71 spindle is the same length as the old but it has an offset to the right. In the case of the ES-51 not only does it have an offset but its much longer.

boudreaux

My apologies. 121 or 126 is correct for the es-51, and lx772.Was reading the wrong line.

Hecubus

This is the BB you need. Notice the right hand side of the spindle is longer:

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Greg-O

thank you thank you thank youuuu

now, for my hopefully last question in this thread.....

if my bike would use a 113 size BB for a normal crank, what size BB-ES51 would it need for an LX?

after that, i think i'm done. thanks a ton you guys

Hecubus

The 121 would be the equivalent of the 113 standard.