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Oil pressure issue / motor rebuild

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MrDavo:
The crank is definitely toast, all the main journals are scored. Ash has sourced me another, see earlier in the thread. I'm dropping the goosed one off with an engineer later to see if he can get the rotor bolt out after I get the points stud off.

The whole bike is that clean inside and out, with fresh pistons and bores as far as I can tell, it was apparently restored fully years ago and never used again. The failure was due to a kinked oil feed pipe, starving it of oil, again see earlier.

There is oil in the motor, I think its never managed to stay in long enough to start to get dirty. That said, I've found that one of the 3 oil pump dowels (with the o ring round it) is slightly distorted out of round, and not a great fit in its slot in the pump, I need to change it - CMS seem to have them. I'm guessing that that alone could be a cause of the low oil pressure, that combined with the kinked hose sealed the engine's fate.

Bryanj:
The low pressure is simply the excess clearance on the mains, the real problem is what caused that

MrDavo:
I think the mains were initially borked by the low oil pressure, caused by the kinked oil feed, it's a bit chicken and egg. Twice after start up the engine has suddenly found itself with no oil pressure at all for a few seconds since I got it as the cold oil hasn't fed the pump fast enough and the pump has found itself pumping fresh air. As the oil light stayed on at higher than expected revs on the first trip to the MOT, I assume whatever event killed the crank had already taken place.

Obviously once you have low oil pressure, it just makes itself worse. This is what I assume caused it, but I will check for a blockage in the oilways. There is an oil metering jet in the head, are there others? It is possible there is still something wrong, but I don't see what, the oil pump has drive and returns oil to the tank.

Another theory suggested is that the motor was completely  rebuilt (this is why its all so clean, it was vapour blasted like new inside as well as out, though not threads or gasket faces) then left for a long time  and was subsequently started up bone dry.

Trigger:
The vapour blasting could explain why everything is toast. If any of the glass bead was left in any of the oil ways, it would of acted like grinding paste. Love to see what the inside of the oil pump looks like.

Bryanj:
Takes quite a bit to remove all the white metal down to the copper, not just a couple of seconds

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