Points gap - tell me again

Setting ignition point gap

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old man emu
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Points gap - tell me again

#1

Post by old man emu »

I'm blaming it on Old Timer's Disease, but can you tell me again about setting the points gap?

I know that I have to centre the vertical line on the flywheel in the viewing hole on the left hand side of the crankcase when the front piston is at TDC of the compression stroke. The circuit breaker has to be in the fully "advanced" position. The mark on the timing cam aligned with the fibre lever.

Next, do I rotate the engine so that the fibre lever is at the first reached highest point of the cam, or do I move the circuit breaker to get there?

Thanks,
Old Man Emu

Don't bother. Found the answer Points gap on front cam lobe
RUBONE
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Re: Points gap - tell me again

#2

Post by RUBONE »

All of what you are describing is for setting the timing, not setting the points gap. Gap is set before timing is attempted and on the highest point of the cam. No need for marks in holes or fibers and dashes. Once the points are set to the correct gap, then the process you describe is used and the timer base is adjusted to just begin to open the points at full advance. The pointer on the cam may not line up, that is of no concern as it is only a reference line.
old man emu
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Re: Points gap - tell me again

#3

Post by old man emu »

So, I've been doing it arse about?

Does that mean that if I simply want to set the points gap, and the timing is OK, then all I have to do is to get the fibre lever to the high spot on the cam and go from there? I don't have to go through all the lining up steps?
RooDog
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Re: Points gap - tell me again

#4

Post by RooDog »

old man emu wrote: Wed Aug 03, 2022 11:12 pm So, I've been doing it arse about?

Does that mean that if I simply want to set the points gap, and the timing is OK, then all I have to do is to get the fibre lever to the high spot on the cam and go from there? I don't have to go through all the lining up steps?
If you habitually set the points to the same gap every time, then the timing doesn't change, as long as you don't move the dizzy....
old man emu
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Re: Points gap - tell me again

#5

Post by old man emu »

Well, I did it like you said. Any change to performance wasn't discernible while the bike was simply idling. Today I just wanted to do the points and start the bike. I am hoping to go got a test ride tomorrow, but the sky is starting to cloud over and threaten rain. You Northern Hemisphere types are boiling in the Sun, but down here we are sloshing around in the mud after flooding rains. Two years ago, this place was a dust bowl.
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