Author Topic: CB550 POINTS TIMING ISSUE  (Read 1032 times)

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Offline BASKET_CASE

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CB550 POINTS TIMING ISSUE
« on: October 20, 2015, 02:34:50 AM »
Im using a timing light to dynamically set my timing. Here's the issue: The timing for 1-4 is advanced at idle (left of mark) which is around 1200 RPM, but at full advance the timing falls within the marks (just on the left tick mark). Idle timing for 2-3 falls on the mark and full advance is also correct.

I can no longer turn the plate clockwise to correct the advance for 1-4 at idle as there is no more space on the plate.

- Points are not new, but are in good shape
- Disassembled/cleaned/reassembled points and advance mechanism
- Gap set to 0.014
- No play in the plate when unscrewed so No need to shim

What am i missing here?
« Last Edit: October 20, 2015, 02:41:01 AM by BASKET_CASE »

Offline PeWe

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Re: CB550 POINTS TIMING ISSUE
« Reply #1 on: October 20, 2015, 03:01:52 AM »
Probably same as I had on my CB750. Sloppy advancer springs that caused full advance way too early.
See problemdescription and solution here. Do the spring job and bike will run well, both at idle and higher revs.
http://forums.sohc4.net/index.php/topic,131339.msg1464986.html#msg1464986
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Updates of the CB750 K6 -1976
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Offline Deltarider

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Re: CB550 POINTS TIMING ISSUE
« Reply #2 on: October 20, 2015, 04:50:50 AM »
I suspect a difference in gap. If possible you could verify with a dwellmeter.
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Offline BASKET_CASE

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Re: CB550 POINTS TIMING ISSUE
« Reply #3 on: October 20, 2015, 11:12:27 AM »
@PeWe

I don't think the springs need to be cut because from what i understand that will make it reach full advance later (increase retardation). Advance occurs around 2K rpm. Its the idle timing that needs to be retarded, but i cant turn the plate clockwise any further.

@deltarider

No dwellmeter, but both gaps are set identically granted i visually observed them to be at the open position before i set the gap.

Offline BASKET_CASE

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Re: CB550 POINTS TIMING ISSUE
« Reply #4 on: October 20, 2015, 12:52:18 PM »
just in case anyone is having similar issues i came across this informative post about shimming the plate

http://forums.sohc4.net/index.php?topic=74929.0