BB Cartridge under torqued but over tightened
I have installed a Shimano ES-70 bottom bracket cartridge on my bike (as part of changing from Shimano 105 to XT series to move my bike's gearing down for a better range for touring).
I have done this on another bike without problems. This time I have an unexpected issue. My problem: When torqued to about 450 in-lbs (the specification range is 435-608 in-lbs -- from Shimano's literature), the spindle has an over tightened feel, not turning smoothly and being rather stiff. When I backed the lockring off to the point where the spindle just ran smoothly, the torque was only about 200 in-lbs. All one bike maintenance book I have says about a situation like this is to "... try again." Ok, fine. What is this supposed to mean? Anyway, I greased the right side threads before I installed the main body of the BB. I used anti-seize compound on the lockring (since it is aluminum alloy while the frame is cro-mo and the cartridge stainless(?) steel. I tightened the right side tight against the BB shell. In addition to the anti-sieze on the lockring threads, I spread a layer of Phil Wood grease on the hard rubber seal on the inside of the lockring. Initially I tightened the lockring by feel using a 12" wrench. Then I checked the spindle. When I found the spindle felt over tightened, I brought out the torque wrench. I am guessing the BB may be defective, though brand new. That is a bit unexpected. Any thoughts? Any similar experiences? (I have searched the Bike Mechanics Forum and not found anything similar brought up before.) |
Answering my own question -- I think.
A slight amendment to my previous post/question: It was actually my daughter who was installing the BB with my verbal assistance. In checking things out, looking for a reason for the problem, I found that she has really tightened the fixed side of the BB cartridge. I did not think that was an issue at first. It is what I had told her to do. But, I loosened it and snugged up using my "calibrated" hands. Then I torqued the lockring side. NOW, the spindle turns freely, with just slightly more resistance that when I try it not tightened down, and there is none of the unevenness. So, now I am guessing that then the LBS prepared the shell, they did not perfectly face the shell. With a very, very slightly less tight fixed side, the lockring can better align the cartridge. How's this for an analysis? |
I think you may be right.Was wondering the same thing.BB facing is not usually the issue with cartridffges it use to be with ball and cone,but there could be exeptions.
|
All times are GMT -6. The time now is 06:18 PM. |
Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.