mcculloch 32cc timing ?
#3
ORIGINAL: tkg
Battery ignition or magneto ignition???
Battery ignition or magneto ignition???
Sincerely, Richard
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From: Riverton,
WY
If the engine has electronic ignition then you CAN adjust the timing, ideal would be 30deg BTDC. If its on the magneto then the timing is fixed at around 24 deg BTDC. If you could make an adjustable timing bracket for the coil then you would also set it for 30 deg.
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From: newark, UNITED KINGDOM
If electronic advance, you could probably go as far as 40 degree at full advance. They are very low compression.
Fixed Mag ignition is a compromise between easy starting and max power.
Fixed Mag ignition is a compromise between easy starting and max power.
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Back in the late 90's I put together two of these with some of the parts from TKG. They had CH battery ignitions.
I played with the timing at different settings on the first one. There was not a significant difference in maximum RPM between 24 degrees and 32 degrees. I eventually set it at 28 degrees. The second one I just set the timing at 28 degrees and left it there.
I played with the timing at different settings on the first one. There was not a significant difference in maximum RPM between 24 degrees and 32 degrees. I eventually set it at 28 degrees. The second one I just set the timing at 28 degrees and left it there.
#7
As Jim has, I've moved my timing around on everything from my converted SuperTigre 51 all the way up to my DLE55 and found NO gain in rpm's after 30 degrees and sometimes it even falls off before I get to 36. The 50cc stuff starts kicking back a lot when you get up around 40. I set all mine at 28-30 now. I've done the research for myself and see no need for any more. (with the exception of my four stroke conversions which are a completely different animal altogether.)
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From: newark, UNITED KINGDOM
The SPE 26 and the McCulloch 32 I have are extremely low compression with small ports. 40 degrees just starts to kickback. 28 degrees loses several hundred RPM the top end.
Any sort of chainsaw derivative / DL / fourstroke glow conversion / twostroke glow conversion would bite your hand off at 40 degrees - I agree!
Bike four strokes typically advance to 40 degrees.
Any sort of chainsaw derivative / DL / fourstroke glow conversion / twostroke glow conversion would bite your hand off at 40 degrees - I agree!
Bike four strokes typically advance to 40 degrees.
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From: lolo,
MT
the mcculloch 32cc right now still has its stock magneto but i want to shave some weight off and go with electronic ingnition. So is 28 degrees a good starting point? Then play with it from there.
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From: Salem,
OR
I'd just leave it there, I'm running that exact engine that massaged the exhaust port to 150 degrees duration and set the timing at around 30 degrees and called it good, it runs like a top.




