We get lots of e-mails thanking us for importing the VO threadless BB. It's saved many a bike with stripped BB threads from the scrapheap. This BB is made for standard 68mm wide BB shells, which is what 95% of bikes have. But what if you have an old mountain bike frame, or one of those odd Raleighs with a wider shell. John-Paul has found a solution which he describes below. And he's posted a photo tutorial. Thanks John-Paul!
I thought I should send in a report about using the Grand Cru threadless bottom bracket. I own a commuter that is built up around an early-1990s Specialized Rockhopper frame, one that has some damaged threads in its bottom-bracket shell. It had become impossible to turn the pedals with any force without producing a grating creak, no matter how much grease or teflon tape I used when screwing in the bottom bracket. I therefore ordered one of the threadless BBs and tried to install it earlier this week.
The first night, I despaired. No matter what I did, I couldn't get the non-drive-side cup to turn onto the cartridge's threads. Eventually I realized that the problem was that the Grand Cru is a 68mm bottom bracket but my model of Rockhopper has an over-sized, 73mm shell. I had decided that that was the end of the road and started pricing new frames.
The next day, though, while I was talking to another volunteer mechanic about my problem, he asked me why I didn't just shave a few millimeters off of the bottom-bracket shell. My automatic response was, "Because that would trash the threa...oh."
On Saturday therefore I did just that: scribed and ground off 2mm from each side of the BB shell, re-tapped and -faced the shell, and then slipped in the threadless BB. Success! A bike that I was almost certain was a lost cause is now riding smoothly and quietly for the first time in about six months. And, if someone has the appropriate tools, they can add those with over-sized BB shells to the list of bikes that they can rescue with this type of bottom bracket. Truly, a great design.
I put together some photos of my process, more because I wanted to show other amateurs how I got it to work: