Well the motor is now 100% built and ready to go back in. I have been even more scrupulous with checking and re checking everything to avoid the crank issue happening again. There was no obvious cause for the crank mashing the rear face of the thrust bearings.
First big thing to change was the piston to head clearance. With the new crank the piston where 20 thou higher than previously. At lowest tilt they where .013" above deck and on full tilt at their highest .031". With the 1.5mm ( .059") head gasket there was no real room to allow for rod stretch. In the turbo bike we allow .040" rod stretch so I took some meet off the top of the pistons to gain the extra clearance.
Crank then the new nitrated crank got clearance, re clearance and clearanced again on both main and big ends.
End float was checked I don't know how many times which I just right ;D
There was one other concern that I had come across before. This invovled the hydraulic clutch bearing. I've seen it before where the spacer behind the bearing has been too thick and when the engine is installed the sits butt up against the clutch cover. Not only not having and air gap as it should but actually being forced up into the clutch cover and also taking up the end float in the crank and mashing thrust bearings. That also being a concern the heights where check over again and on both the engine and gearbox side and was all fine as I had hoped with the required 2.4mm air gap.
With every thing checked it ready to go back in. Plan is for Monday.
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