I got some fancy new carburetors a couple of weeks ago, and of course the outlet on them doesn't match the inlet on the head. I could have bought adapters but they take up an extra inch of space that I'd rather use for the airbox. So it's time to do more lathing.
Start with some round stock that is just the right OD, so I only need to turn out the middle. The downside of this is that the parts are a little eccentric, just like the rest of the bike.
The stock was supposed to be long enough to make 4 spacers and has a little extra for clamping. It turned out to be long enough for 5; the four I needed and one screwup.
Start by drilling out the center so that a boring tool can go in.
Then cut out the middle to the right diameter
The spigots are 30.0mm OD, so this is a .1mm press fit. It felt about right. The final part I did was more like .15mm and it was a bit on the tight side.
Cut the part off:
Side note: using the parting tool this far from the chuck didn't work very well until I used the tailstock to secure the part.
Present the parts for inspection:
Press it on the spigot, with sealant:
One done, three to go.
As mentioned, I did screw one up. It would have been the last one but the cutting tool got dull and started chattering. By the time I figured out what was going on it had cut the part to 30.0mm which was a nice slip fit, but not a proper press.
Finally, fitting one up to the carbs.
All in all, a good warmup to the shock bushing spacers that need to be made.