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Road Capt
04-23-2011, 09:47 PM
Is it possible for the Ignition Module to fail in the full advanced mode?

I'm trying to time the motor and am getting full advance inticator (dot on the flywheel) at idle and at higher rpm's.

I've checked the VOES ...it is good...I checked the ground side of the wiring and the module side...ground is good....module side is not grounded...like it is supposed to be.

Any ideas?

junior
04-24-2011, 12:42 PM
well, that is actually what is supposed to happen. harley voes are hooked to manifold vacuum- not ported like the cars. so rather than advancing timing as throttle opens (cars) it retards timing under load to avoid detonation. try pulling the vacuum line with the light on there- the dot should disappear....

if you are really nit-picky the voes is adjustable (to a point). yours is likely set to open in the 5 in/hg range or so...

j

Road Capt
04-24-2011, 05:20 PM
well, that is actually what is supposed to happen. harley voes are hooked to manifold vacuum- not ported like the cars. so rather than advancing timing as throttle opens (cars) it retards timing under load to avoid detonation. try pulling the vacuum line with the light on there- the dot should disappear....

if you are really nit-picky the voes is adjustable (to a point). yours is likely set to open in the 5 in/hg range or so...

j
I have the VOES wires disconnected so the switch and vacuum do not affect it.....I still get the full advanced timing?......I can only think that the module is stuck or failed in full advance.....Any comments?

junior
04-24-2011, 05:49 PM
timing is set at idle with the voes connected (vacuum and electric). there is no "gradient" in the timing adjustment on the stock box. it is either advanced (@35 degrees- the "dot") or not (@10 degrees less). the voes tells it to advance or not. when you start it, no vacuum, no advance. so it cranks and fires @25 degrees. as it catches up, there is vacuum and it goes to 35 and there it stays. grab a handful under load and the vacuum drops and the timing retards again (so it doesn't detonate).

did you adjust the timing plate? it is possible that someone did as you are doing (voes unhooked) and now the timing is too far advanced. hook everything back up, loosen the two screws and then set it. at that point check and see if the mark disappears when you remove vacuum. let us know what happens...

Road Capt
04-24-2011, 10:34 PM
Yeah as I thought about it today it seems best to put it all back together and start from scratch The info about firing @25 degress when starting is key...it explains alot of what I was seeing. Thanks, probably get into it tomorrow.....I'll keep you informed.....


timing is set at idle with the voes connected (vacuum and electric). there is no "gradient" in the timing adjustment on the stock box. it is either advanced (@35 degrees- the "dot") or not (@10 degrees less). the voes tells it to advance or not. when you start it, no vacuum, no advance. so it cranks and fires @25 degrees. as it catches up, there is vacuum and it goes to 35 and there it stays. grab a handful under load and the vacuum drops and the timing retards again (so it doesn't detonate).

did you adjust the timing plate? it is possible that someone did as you are doing (voes unhooked) and now the timing is too far advanced. hook everything back up, loosen the two screws and then set it. at that point check and see if the mark disappears when you remove vacuum. let us know what happens...

RacingOrangeRoadster
04-25-2011, 12:53 PM
I'm not working on a bike, but I just wanted to say Thanks to Junior for all the information you give us.

junior
04-26-2011, 02:52 AM
heck, it's fun for me. i don't have a project now so it keeps my mind sharp trying to see what goes on with other guys bikes....

always glad to try and help-

j