Hi All,
I am rebuilding a 1930 model 18 motor for a friend and wanted to confirm what the valve timing specifications are.
I have a book called Motor Cycling maintenance series Norton motorcycles 1928-55.
In the data section it says Model 18 1928-1931 compression ratio-6.0-1
Valve timing- Inlet opens 1/4" BTDC
Exhaust closes 1/4" ATDC
Ignition Timing 1/2" BTDC Fully Advanced
Tappet Clearance Cold Inlet/Outlet 0.003
Can anybody confirm that this is correct.
Cheers
Andy
Singles - Engine Data
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Andy, My 1930 Norton…
Andy,
My 1930 Norton Maintenance manual lists the following data:
Exhaust opens 0.75" (or 55-60 degrees BBDC).
Exhaust closes 0.25" (or 25-30 degrees ATDC).
Inlet opens 0.25" (or 25-30 degrees BTDC).
Inlet closes 0.4375" (or 40-45 degrees ABDC).
Tappet clearance is 0.003" for both inlet and exhaust valves.
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Agree with Andy as above but…
Agree with Andy as above but mine was really hard to start so l set ignition timing at 5/16 BTDC. With a bit of choke now and a few purgr kicks after a flooded carb with lifter in she starts first time...trial and error each one is slightly different
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I agree with Ian. Why not…
I agree with Ian. Why not set it to 5/8 and also mark the lever at 5/16. Too far retarded and it will be sluggish and hot.
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Thanks everybody for your…
Thanks everybody for your replies, I will try the 5/8" for the timing and go from there.
Cheers
Andy
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Hi Andrew.......the attachment if from the E.M. Franks Maintenance Book for Nortons - circa 1932 onwards. The info may be of help.