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Discussion Starter · #1 ·
I originally posted this in the "Tips and Tricks" forum, but am unsure whether that was the right place, so here it is again:

I just bought a '72 T120 engine (650) in a '67 TR6 frame. The bike (which isn't currently running) came with a brand new shop manual, good for 1963-1970 650s. How much of the information on these years will translate to my engine, which is from an OIF bike. Are all the 650s (pre-units included except for the jugs and head of course) pretty much the same, at least in terms of internal parts?

That is, it seems to me that the dimensions of the cylinders seem to be the same, but I wonder if I could, say swap a '72 head with a '66? Or if the tappets from a '55 T110 will fit '72 T120, etc.
 

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I'd stick with 65 and later for best match. I think the metric main bearings came in 73, so you are probably okay there.

Last thing is threads; fine and coarse went through transitions 68-69 and even 70.
 

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Discussion Starter · #3 ·
That's good advice in terms of parts, but what about all the specs? Logic and intuition tell me that they're probably the same, but with Triumph, you never know...
 

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Discussion Starter · #5 ·
Ha! Good point, however, I've run into a few guys who are savant-like when it comes to part numbers/ specs!
 
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