Motoscrubs.com

You can check the internal tab washers under the securing nuts of the sprocket and both crankshaft threads. However, you have to take off at least the primary and distribution covers to get access, if you want to find out if the main parts of the engine have not been touched. In the factory, the outer tabs were bent against the locking nuts precisely, so their surface must be smooth, without scars or other damages. If such marks are visible, the tab washers had been re-used, somebody might have worked on it and possibly splitted the case.

Hans

I have been in contact with an old friend that is good at rebuilds. He will do it for me. He has rebuilt many twins and singles. He even owned a genuine Imola race bike.

When I was 21 I bought a 750gt in a million bits. One of my best friends was the factory parts manual. I was on compo from crashing another bike, so I had all the time in the world. I was, at the time a 3rd year fitter and turner apprentice. When I finished it ran like a dream. I now, at 57, have my fathers 450 desmo to do. I think with care, patience and perseverance you, or your friend can do it? But, perhaps, if you have any doubts, might it be better to pay an expert, as if thing go awry, it could be more costly? Depends how deep your pockets are, but there is great satisfaction from doing something yourself. Good luck with it.

Patience is the key with these engines. I don't think that shimming bevels is difficult, but it needs patience. There are some jobs that can't be done by a home enthusiast, like big-ends and valve seats, and probably valve guides, but most else needs patience and perseverance. I rebuilt a 750 bevel engine and then rode it to Spain for a holiday, and it was a trifle rattley! When I got home I reshimmed all the bevels again using the knowledge that I had learned the first time.

Thanks for your encouraging words. I am ok with getting it done for me instead of my mate and I probably getting a little testy at each other trying to do it at home. The old mate I mentioned that I am going to use has probably done hundreds of twins and quite a few singles. He has a nice collection, 450 shotgun 750 gt 750 Sport and possibly more.
Cheers and I will update as progress allows.