Timing Advance stickingTiming Advance stickingI recently brought a dormant 305 Dream back to life. It runs good except rpm's do not return to idle quickly. I thought initially that the slide was sticking, but that is not the case. The timing advance is sticking as confirmed by a timing light. After 6-8 seconds it retards and speed decreases. I am hoping since the advance unit lives in a lubricated environment, it may improve after riding it for a while. The springs may be weak. I can move the points cam and it returns, bit does not snap back. I assume in order to service the advance unit, I will have to drop the engine to remove the head plate. Is that correct? You thoughts and ideas appreciated.
Re: Timing Advance stickingYou are pretty much correct on everything.
Fortunately the springs can be replaced once the top cover is off. I have springs here. They are different form the CB/CL type. ..... ....lm
Timing Advance stickingThanks for the prompt reply. I'll ride it a little to see if anything changes. If not , I'll PM you to arrange buying a set of springs. This bike is the newest member of the Critter crew. It's known as the Polecat. I think you know these guys. Fun bunch.
Raceman
Re: Timing Advance stickingAs you tell use the points cam is slow to return.
YOUR SPRINGS ARE SHOT. Time won't fix that unless you are magic. .............lm
Hmmm, that's interesting. I have the same slow to return idle. The slide, cable, and throttle assy. are good. My points cam snaps back pretty good though. Can you change the springs from the top cover or does the cam sprocket have to come out?
1967 CA78
1965 CM90 The value of life can be measured by how many times your soul has been deeply stirred. Soichiro Honda
Pack the head area under the cam sprocket and carefully remove and replace the springs.
Be careful not to stretch the new springs. .......lm
To make sure the points weights are really returning to their stops at idle, check by using a timing light, confirming your original static setting. If you don't have a timing light, press on the end of the points cam (with the cover removed) with the engine running, to exert some drag. If the idle drops right down to spec, that should confirm the unhappy springs. Be aware that some of the replacement CB advancer springs being sold are actually CA style springs, and will not work properly. Regards, Chase
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