overheating

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Overheating right exhaust pipe. It gets red hot idleling (with a few revs thrown in) Iv'e riched up the carb a bit with a turn of pilot air screw, but I think it's still running too lean. Would rasing the needle a groove or two solve problem? It's a 69 Commando fastback with amel carbs. Cheers...
 
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Hi,
You didn't say what you are running for ignition. If you are still running the original point system consider checking the timing. Retarted timing can cause the glowing pipe condition you describe, and with the original point system it is possible for one side to be retarted exclusive of the other side.
GB
 

L.A.B.

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reidpik said:
Would rasing the needle a groove or two solve problem?

The needle (and needle jet) controls the carb mixture between roughly 1/2 and 3/4 throttle.
Above and below those throttle positions its affect on the mixture drops off, as the main jet takes over (3/4 to full throttle) and the 1/4 to 1/2 throttle mixture is controlled by the size of the throttle slide cutaway.
 

ML

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Have you tried checking that the carb mounting flange is bolted up evenly?
Those bloody Amals have a habit of warping and letting extra air in that over leans the mixture throughout the rev range.

Also make sure your spark plug is the correct grade.

Mick
 
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Check your ignition with a strobe light, doing it static can often be wildly out. I had identical symptoms to yours and found mine about 20 degrees out.
 
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Check the exhaust valve clearance, might be a little too tight.
Cash
 
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