Back in Aug I had the pleasure of going out to Utah and working on the Four Aces Cycle pit crew. Wes is and his friends are a first class bunch of guys. I had never met any of them before and after one email exchange I felt like we were old friends when we met. Thanks for the good times guys. HERE is a link to my flicker slide show with 200 photos. Get the Salt Fever and see you there next year
all photo credits to Frank Zerkel
After looking at the mess that was the head and steering parts I spent a day trying to figure out how to fix it. I really didn’t want to make a new stem or weld and reshape the existing one. Research into bearings (thanks, McMaster-Carr for having the best industrial supply business in the world) showed that no available ball bearings would fit the tight dimensions between the fork and frame head tube. I started thinking about how make up some bronze self-lubricating bushings instead. Couldn’t find any sizes that were plug-and-play so I made up a sandwich of two bronze bushings and a steel shim between them, pressed together concentrically. Worked great, if a little too much work for such a simple goal.
Once these bushings were made up, I counterbored one of them for a steel thrust washer so the fork crown (aluminum) wouldn’t get worn away over time. You can’t tell it’s even in there in the pictures. Clean.
The head tube needed to be bored some for press fit of the bushings. Normally I’d have just turned the bushings down, but the frame had a big seam in the tube that would have prevented a proper fit. I mounted the trike frame to the milling machine table in kind of an oddball fashion, but it worked. I was too lazy to indicate the tube so just eyeballed the setup resulting in the bore being slightly eccentric with the original hole. Whatever. It’s a tricycle, not a track frame. It is silky smooth assembled with zero detectable play.
‘Til next time.
Jason
Frame mounted on the table for boring. Note the three-piece bronze bushing next to it.
Finished fit of fork in frame bushing.
The top collar needs to be machined down a little as the stack height has increased slightly. Easy enough.
Finished frame and fork. Beautiful castings. Reminds me of the days I used to sweat high-dollar SE Racing framesets that lawn mowing money wouldn’t cover.