Vintage Motorcycle Eccentrics

The last pieces to repair on the RFM are the mud guards. They actually welded up ok. Just a bit tricky considering they are old and very thin. George loaned me his mini english wheel which was a life saver. It does a beautiful job of removing those tiny little divots and wrinkles. The front portion of the rear fender was originally for a 500cc Comet which has the drive chain on the left side, so there is a flattened area where the mud guard must clear the chain. With the english wheel I was able to reshape that part and then flattened an area on the right side where the Shadow chain passes.

The mudguards are as close to perfect as I can get them so will polish them out for the final finish.
Meanwhile I laid out 8 inspection caps/cover for cleaning. They look worse than I recall so here goes another round of cleaning, deburring and polishing, and without damaging the 'Vincent' logo. I made a tool to screw them into so I can re-cut the hex just enough to clean up all the wrench and plier marks. It will be done on the mill using the rotary index tool. It also has a removable stem so I can use it with the hand drill to turn the part when finishing the circumference.

After years of using pliers instead of the correct spanner it shows.

With the fixture in the rotary chuck I skim cut just enough to remove most of the wrench marks. The original hex was a bit over 1-5/8" and is now slightly under. Next is more deburring, sanding and buffing..

Much nicer.
Did you make a tool that fits on the slightly modified size? Or does original one still work fine.


BTW, I got my wiper setup going on my Vaporhoner. Still waiting for the intermittent board- but it works very well. I do need to make a little cover for the motor- then a mount for switch and adjustable intermittent operation.
The motor I got was a rebuilt one from a Ford van- so it has park (which is nice).

I will make a new spanner using some 1/4" thick 2024 aluminum. I'll have to scope out your wiper installation, sounds nice.

The inspection caps are finally finished. Quite an exercise in getting the finish and not disturbing the logo. It started with a 2" rotary sanding pad with 400 grit, then 600, 800 and 1000. Then to the a felt wheel on the buffer with white rouge.
Finally into the ultrasonic cleaner to remove all the polishing compound. With final inspection, they were coated with Shine and Seal. On to the next part of the project.

Wow, they look amazing John.

Got around to making a spanner for the caps. The original K1 spanner that came in the tool kit was about 1.664" hex. To clean up all the wrench marks they are now 1.625" hex. The new spanner is 7075 t6 aluminum so will be strong enough. I will make an open end version while I'm at it.

Looks great. I was wondering how you were going to make the ‘square’ corners. But doing them relieved instead works better and much easer to do also.
I will keep that in mind.

Have you ever cut a woodruff ‘slot’ inside a flywheel taper?

I made a couple of mistakes but the dimensions are correct so will live with it. This old rotary table has seen better days and was difficult hitting the 60º marks.