About a month ago i installed a Molnar nikasil barrel, a Fullauto head, JS pistons and long rods and BSA lifters and a mild cam with extra lift to my 72 750. Also an 850 crankcase. Old cases had cracks around top threads from nuts being over tightened. Barrel and pistons were worn out. Head was not much better. Was hoping to achieve a quiet engine that vibrated less below 3000 rpm and had more go below 4000 rpm. Pistons were graphite coated with very little clearance and i now have a very quiet engine with no audible piston slap hot or cold. I re balanced crank to 52% wet and with much lighter pistons i now have an engine that is a lot smoother below 3000 rpm and is quite acceptable. It is very smooth at 2000 rpm around town in top gear, unlike before when it was a teeth chatterer! The new cam has inlet timing of 245 degrees at .050", and .362" lift, and now the engine really wakes up at 3000 rpm instead of 4000 rpm previously. CR is 8.5:1. Altogether with the TTI 5 speed and single TM34 carb the bike is now a real joy to ride. The exhaust is considerably louder. Spun it out to 6500 rpm in 3rd up a hill today. Probably for best acceleration changing at 6000 would be good with the single carb. The Norton and the Velo 500 competed at the Collingrove hill climb 2 weeks ago. Both bikes have similar cams and both performed very well. Now a happy chappy! And the money? oh well! Graham
750 Nikasil barrel and Fullauto head
- Thread starter velo54
- Start date
Fast Eddie
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That’s sounds like a great build Graham. Nice one
Schwany
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2000 RPM in top gear in town? Must have high speed limits in your town. 
I had a quiet 750 engine for about 400 miles 3 years ago. Wish it would have stayed that way. Basically the same parts that you used except iron liners in the Molnar barrels, a JS2 cam, and FCR carbonators.
Congratulations on your stealthy build.
Never add up the receipts.
I had a quiet 750 engine for about 400 miles 3 years ago. Wish it would have stayed that way. Basically the same parts that you used except iron liners in the Molnar barrels, a JS2 cam, and FCR carbonators.
Congratulations on your stealthy build.
Never add up the receipts.
Schwany
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Not wrong just typical of an old Norton. And I know nobody else has ever heard a sound out of their Nortons. Every time I hear something like that in a forum, the BS flag is thrown in silence.
