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Author Topic: Mechanical advance  (Read 546 times)

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Offline Dirty Steve

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Mechanical advance
« on: September 25, 2016, 01:06:53 PM »
Hi all,
My mechanical advance is not fully advancing. I took it apart and cleaned and lubed it and the problem persists. What other issues might I need to look at?
Thanks.
Stock CB 750 K5
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Riding motorcycles will make you a poet. Working on them will make you a philosopher.

1975 CB750K5 with stock airbox, exhaust et al...

Offline martin99

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Re: Mechanical advance
« Reply #1 on: September 25, 2016, 03:24:38 PM »
Springs stretched?

You could buy replacements, or try shortening the ones you have.
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Offline b52bombardier1

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Re: Mechanical advance
« Reply #2 on: September 25, 2016, 04:06:39 PM »
If it will not fully advance, that usually means it's dirty or rusty. Most of my advancer problems are more related to weak springs leaving it too advanced - unable to pull the counterweight arms back in at idle rpm.

Rick

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Offline flybox1

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Re: Mechanical advance
« Reply #3 on: September 25, 2016, 04:17:46 PM »
If the spacers above and below the heel of the advance weights, where the (c-clip is) are gone/worn, you wont hit full advance. Check for play at the toe of the advancer weight.  It needs to be minimal
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