Bike Forums

Bike Forums (https://www.bikeforums.net/forum.php)
-   Bicycle Mechanics (https://www.bikeforums.net/bicycle-mechanics/)
-   -   BB Cartridge under torqued but over tightened (https://www.bikeforums.net/bicycle-mechanics/19101-bb-cartridge-under-torqued-but-over-tightened.html)

sakarias 12-22-02 07:38 PM

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.)

sakarias 12-22-02 09:49 PM

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?

pokey 12-23-02 07:52 AM

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 07:18 PM.


Copyright 2018 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.