NitroTate Posted June 1, 2009 Report Share Posted June 1, 2009 Ok electrical experts, I have two questions for you; Bike was running like dog crap and I suspected electrical because no matter the jetting it still ran poorly, cutting out and missing... Question 1: I changed out my old stator with a new one, (RM Stator) and the bike would not start, it would pop every once in a while but wouldn't start. I began by checking the pickup coil gap and as I got the pickup coil closer to the flywheel it would act more and more like it wanted to start but still would not. I tested the pickup coil and it tested good, "should be 94-140 ohms" and tested at 106 ohms. I went back to my old stator and tested that pickup coil an it tested out at 120 ohms and with the old stator on the bike would start. So then I put my old pickup coil on my new stator and the bike starts just fine so the problem is definitely the new pickup coil that tests out at 106 ohms. My big question is why would it make such a big difference from 120 ohms down to 106 ohms when the 106 is still within spec?? Question 2: I actually found out why the bike was running bad, it was a bad CDI. I had a spare CDI sitting around so I went to put it on and the connectors were different so it's obviously from a different year. I spliced on the old connectors to the other CDI and plugged it in. The bike would finally run good but the odd thing is, there is an extra wire coming from the newer CDI (green with yellow stripe) what is this wire? I can't find it in any diagrams and for some insane reason the bike only starts if I have this wire grounded but then once the bike is running it runs like shit until I disconnect that wire and then it runs great. sorry for long post but thanks for the help in advance!! Tate Quote Link to comment Share on other sites More sharing options...
okbeast Posted June 1, 2009 Report Share Posted June 1, 2009 LOL ya gotta love electrical gremlins. Hopefully someone can help ya out. Quote Link to comment Share on other sites More sharing options...
AKheathen Posted June 1, 2009 Report Share Posted June 1, 2009 (edited) .....*staring at avatar.....again*.......... ok. the pickup coil thing- it was bacause of the cdi. less resistance would drop the weakened voltage feeding the pickup coil, if that makes sense. if i remember correctly, the green wire is the brake, or clutch, so that you don't start it in gear without being able to stop it. maybey you can mount a momentary switch by your clutch lever to start it. i bet if you put the other pickup back on, it'll work fine. Edited June 1, 2009 by AKheathen Quote Link to comment Share on other sites More sharing options...
NitroTate Posted June 1, 2009 Author Report Share Posted June 1, 2009 .....*staring at avatar.....again*.......... ok. the pickup coil thing- it was bacause of the cdi. less resistance would drop the weakened voltage feeding the pickup coil, if that makes sense. if i remember correctly, the green wire is the brake, or clutch, so that you don't start it in gear without being able to stop it. maybey you can mount a momentary switch by your clutch lever to start it. i bet if you put the other pickup back on, it'll work fine. Ok gotcha yeah I was wondering if that could have been a clutch or brake check-wire. That makes sense why it would do that but there's got to be a way to bypass it wouldn't you think? My wife's bike has the same wire running through the harness somewhere but it starts regardless of brake or clutch etc. so it must be tied into something that allows it to start and still run good without the brake or clutch/gearing. I hate to mess with running a momentary switch and all that crap. I'd rather tie the bitch off to something if I can. I tried the new CDI and the other (newer) pickup coil and it still wouldn't work... weird. But it works with the old pickup so that's what I have on there now. Quote Link to comment Share on other sites More sharing options...
blowit Posted June 1, 2009 Report Share Posted June 1, 2009 Ok gotcha yeah I was wondering if that could have been a clutch or brake check-wire. That makes sense why it would do that but there's got to be a way to bypass it wouldn't you think? My wife's bike has the same wire running through the harness somewhere but it starts regardless of brake or clutch etc. so it must be tied into something that allows it to start and still run good without the brake or clutch/gearing. I hate to mess with running a momentary switch and all that crap. I'd rather tie the bitch off to something if I can. I tried the new CDI and the other (newer) pickup coil and it still wouldn't work... weird. But it works with the old pickup so that's what I have on there now. All the pickups you are testing should work just fine. They are a very simple design, they do NOT have any power going to them from the CDI. They produce a voltage spike as part of a hysteresis circuit by bringing a magnetized ferrous object near the sensor. The voltage going back to the CDI is around .8V. This does not affect spark performance. It is merely a triggering mechanism. Anything close to 100ohms should work just fine. Not grounding a CDI can kill them because the device is not able to properly shunt voltage to ground, thus can over heat or over volt. Without looking, I do not remember the green/yellow wire but your problems still seem fishy. The brake (rev limit) circuit should not prohibit starting. Other circuits would just kill the bike. I will look at the wire in question but I still suggest looking over those grounds really well. Brandon Quote Link to comment Share on other sites More sharing options...
blowit Posted June 1, 2009 Report Share Posted June 1, 2009 G/Y is the rev limit circuit of the CDI invoked by the parking brake switch. When G/Y is NOT grounded to chassis or otherwise the B wire of the harness, the CDI should perform normal function. Inversely, if G/Y is connected to B or chassis ground, the CDI spark performance shall be limited to 2,300rpm. The bike should exhibit a normal start and run condition with the G/Y wire not hooked to anything. Puzzling. I would certainly take another look at grounds. Remember that ground from engine to chassis must be solid and is commonly missed when a frame is painted or powdered. B Quote Link to comment Share on other sites More sharing options...
NitroTate Posted June 1, 2009 Author Report Share Posted June 1, 2009 All the pickups you are testing should work just fine. They are a very simple design, they do NOT have any power going to them from the CDI. They produce a voltage spike as part of a hysteresis circuit by bringing a magnetized ferrous object near the sensor. The voltage going back to the CDI is around .8V. This does not affect spark performance. It is merely a triggering mechanism. Anything close to 100ohms should work just fine. Not grounding a CDI can kill them because the device is not able to properly shunt voltage to ground, thus can over heat or over volt. Without looking, I do not remember the green/yellow wire but your problems still seem fishy. The brake (rev limit) circuit should not prohibit starting. Other circuits would just kill the bike. I will look at the wire in question but I still suggest looking over those grounds really well. Brandon Yeah it's very confusing but I switched the two stators out 4 damn times with the new CDI on before I decided to swap the old pickup onto the new stator and then everything worked perfect except for the goofy green/yellow wire gremlin. I have very solid grounds on the harness, I've checked them multiple times but I will definitely check again. I'll find out what happens when I get home tonight. If it starts I'll be happy, but if I have to ground that damn green/yellow wire I'm gonna be stumped... Quote Link to comment Share on other sites More sharing options...
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