Head and Shoulders

The hardest part of the engine build is behind me with the crank and crankcase assembly complete. I put in about 4 house in the garage today to get as much done on the engine as possible before it goes back into the frame. The exhaust manifold is soaking in a diesel bath to aid the de-coking, I want to put on the engine before it goes into the frame. I'm going to have to spend a few hours organising the space to make the bike rebuild easier.

Reunited

I had a productive evening today, managed to get the gearbox and left hand crankcase assembled. Again to fit the bearings in the crankcase I heated it to 100 degrees and popped the bearings into the freezer for about an hour. In preparation to fit the left hand case complete I cooled the left hand crank with some cooler blocks and compressed air . . . and yep the case just slid down to meet its partner.

Crank-In

The engine re-build has officially started. The right hand main bearing is on the crank and in the right hand case along with the shim and seal. First step was to fit the right hand main bearing on the crank which I did by cooling the shaft in the freezer for 1 hour and heating the bearing for about 5 minutes in a tin can with a gas torch. The bearing just slid on with no tipping or tapping. To then fit the crank shaft to the right hand case I again cooled the crank in the freezer for about 90 minutes and heated the crank to 100 degrees C in the kitchen oven - they just fell into place!

Red Engine

Well its official, the engine rebuild can start. I have the cases, Barrel and head painted a lovely Red with heat resistant spray paint.

Rear brake disc

Here is the rear brake disc with its lovely rust formations. There is little or no wear on the disc and the thickness is exactly 4.1mm at both the inner and outer edges. I probably wont replace this as it is only the rear disc.

Into the Oven

Finally got the crank cases, barrel, head and water jacket cleaned up and ready for spraying. I used a dremel with a stainless steel wire brush. I managed to source high temperature spray paint in Red. I assembled the parts and sealed off the bearing holes etc with masking tape to prevent paint from entering inside. The oven was heated to 75 degrees, could have gone higher but didnt have any oven gloves!

Prepping the crank cases

Following on from the last post on cleaning up the top end and removing the corrosion I am starting the crankcases this week. All the bearings have been removed and the joining surfaces are masked off for protection against accidental scratching with the dremil and wire brush.