The contact area on the expanding insert is aluminum, softer than steel threads. The insert expands onto harder steel threads.
How could it damage the threads expanding or just pressing onto them? You should see what the two steel set screws have done to the softer metal eccentric on my Santana. That uses less contact area than this thread less BB has.
One the kids at VO said that one they had installed did have marks on the insert from the threads.
I think it is a great solution, once I figure out what crank set I am going to use on my Motobecane tandem will buy two.
Steven Johnson, Millersville, MD
Date: Tue, 15 Dec 2009 12:06:52 -0800 From: Thomas Adams <firstname.lastname@example.org>
For BB's with damaged/off line threading, Velo Orange now makes a "threadless" bottom bracket that looks to be designed to resuce these frames.? It's called the Grand Cru threadless BB, and uses an expanding sleeve that is pressed into the threads, damaged or not, as the adjustable cup is tightened.? This looks like the BB only locks onto the left side threads,?but it's a neat looking fix.? It's also supposed to be a fix for french or swiss frames where you don't want to spring for a Phil BB and/or can't find an orignal set of cups.? $60.00, JIS taper, lengths from 103 to 127 mm.? Presumably no offset, so you may have to shim the fixed cup or accept the left crank being a bit further outboard.?
However I presume a grossly out of round BB shell would not be solved by this unit, and I'd worry about damage to threads in a sound BB that you just can't find cups for.? Anyone from V-O care to comment?
Tom Adams Manhattan, KS USA
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