Its Saturday, wife is at work, time to get some progress
Backtracking a bit, Thursday gave me a few hours spare workshop time, There was a spare electonic ignition from one of Jin's M90s on the shelf, better than the points and big coil supplied with the kit IMHO as the unit and battery can all be hidden in the base. A mounting plate was needed to position the Hall effect sensor inside the crankcase and a magnet fitted to the crankweb.
The 2k paint on the base was now dry, so time to mount the crankcase square on the base and line ream the main bearings, things were going well again :-)
Next was the crank. The crank webs are pre milled but top hat bushes need to be turned to increase the surface area of the soft soldered bond.
And this is where the good luck run stopped, everything fluxed and fitted together ready for soldering, heat applied and the solder flowed nicely on the brass parts but refused to flow onto the silver steel shaft, clearly time to stop for the day.
After work on Friday it was time to clean up the mess, the shaft was still straight and cleaned up pretty well and with many applications of flux in finally tinned with solder. This time i had to assemble it hot, a piece at a time which was not easy, but got there in the end. The crank was still reasonably straight even after drilling the webs and hammering in the roll pins to give it strength.
I forgot to take pictures of the crank nightmare, was too concentrated on trying to recover the the disaster.
A few well plced hammer blows had the crank down to less than 1 thou runout. Had to shim it to get the crankpin central to the bore (i measured with the main bearing inside out and machined 1mm too much off the collar... duh)
OK back to Saturday, crank was done, next were the timing gears, again the gears were pre made but bushes had to be turned to fit them on the shafts. The camshaft has only one bush bearing and with the thrust of the cam was already wobbling, time for a mod! Needs a longer bush me thinks, but can't move the cam gear inwards as it hits the crank. In the end i added 2mm on the inside of the bush and recessed the cam gear to sit 'over' the end of the bush so the gear was only 1mm further toward the crank. The outside of the bush gained an additional 2mm and the cam follower fork on the inside opened up to slide over it. This gave me an extra 4mm of bearing area. The pic below shows the new and old bushes.
Recessed cam gear
Cam follower fork opened up to ride over the outer edge of extended bush
All went together nicely with no wobble this time
The govenor spool was turned and fitted
Next up are the flywheels, i rough turned them and painted, couple of days for the paint to go off and i can finish em off.
And that was a very enjoyable Saturday, time to get a shower and something to eat and off to pick Lena up from work.