The Gremlin is back.

thuban

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77 650D
Question: Can the safety relay be AFU and intermitently providing a ground to my red/w wire, grounding my coils below a certain rpm, Like on kick start, without blowing the 20 amp fuse and making magic smoke?

Would explain why it runs fine above 2K with voltage on the Yellow, the red/w is not grounded and the coils are powered.

Bike starts and runs fine. Then go to re-start and it just kicks through and every few kicks or so it spits. Finally it starts. It will run if you keep a bit of rpm under it, 1500 to 2 K.
I had narrowed it down to the engine stop switch. Pulled it apart, it was nasty and cleaned it. Put 70 miles on the bike, perfect and would start every kick. Hey, I buy a whole new right elect control from Mike's and install it ( with some effort). No more problems from this, right?

Then I get the Pea Shooters on and can't wait to try it. Off I go on 12 mile run over to son-in-laws. About 10 minutes and time to head home. Got about 30 minutes of day light and don't want to ride in the dark. Hell, no it won't start! It kicks thru and every so often Spits! Got it started and let it drop to Idle and it shuts down. Kick, Kick. It starts and I keep a little rpm under it and head home. Lucky only about three stops to the house. Works just perfect.
Every light is working, Tells me I have power out of the Ignition switch on the brown wire.
But is the engine stop switch getting power from the brown wire running to it? I will assume, for many reasons, nothing is wrong down stream to the coils points and such because Items down there won't affect Both Cylinders at the same time.
So, if it's not the Stop switch... ( and at this check I do have Batt voltage to the red/w wire at the coil connector feeding both brown coil wires and power at the coils. (which is not always true or I would not be having the problem.)
On the same red/w wire out of the stop switch supplying power to the coils, is the brake Lining ind. 77 dosen't have it. Next - the red/w powers the Safety Relay. I have the blue/w to the Start Sol unplugged. But, that red/w is still connected to the safety relay which has a black (ground) and yellow ( Alt signal wire) and a red wire that dosen't show on the wiring sche. but probably relay power.

Talk about a weird duck! I should be able to disconnect the red/w wire at the Safety Relay, which would alievaite any grounding of this red/w wire that powers coils. I don't think the yellow wire from the Alt cares if there is anything down stream reading it or not?
Or just unplug the safety relay all together?

What say you, Monkeys of the Grease and keepers of the Yama-knowledge?
 
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Your '77 should have the single safety relay, for the starter only. The later ones are doubles, also containing a relay to automatically turn the headlight on. So, you should be able to just unplug the whole thing since you're doing kick only. Although I've never heard of the safety relay issue you think you may be having, I suppose it's possible. Disconnecting the unit completely should tell you if it's at fault. Also, don't rule out your new handlebar control. Wouldn't be the first time something of questionable quality came from Mike's, lol.
 
The Safety Relay: Works buy providing a ground to the starter button and doing the magic to turn the starter. Exception, engine running, if there is enough engine rpm for the Alt to provide voltage on the yellow wire, the starter button no longer has a ground thru the relay and you won't grind the starter.
The safety relay kills power to the starter solenoid when it's energized by the yellow wire, not as you describe (providing a ground). If you have the starter disabled, yes... you could just unplug the safety relay.
 
5Twins said
"… Also, don't rule out your new handlebar control"
5Twins, don't we know it! Right, single relay. I had key on and was watching the voltage at the coils. I did the wiggle test on the wires, rolled de bones and shook a chicken! Batt voltage didn't change. I disconnected the red/w wire at the sol. I'll see what that does. If this happens again, I'll rig up a small led with one side to ground and the other lead hooked to the red/w at the coils. It will tell me what the power at the coils is doing, on, off or flicker, starting or riding.
Thanks 5T
 
The safety relay kills power to the starter solenoid when it's energized by the yellow wire, not as you describe (providing a ground). If you have the starter disabled, yes... you could just unplug the safety relay.

Yep, let me edit that out. Don't really need it. I was looking at the safety relay side of the equation not where the solenoid got it's power.:thumbsup:
 
Does your e-start work? If so does it work when the bike is acting up?
 
I had key on and was watching the voltage at the coils.
Is the voltmeter attached to one of the positive studs at the coil or connected to a wire upstream of the coils?
I agree it sounds electrical. I would still make sure you are getting fuel to the carbs.
 
Is the voltmeter attached to one of the positive studs at the coil or connected to a wire upstream of the coils?
I agree it sounds electrical. I would still make sure you are getting fuel to the carbs.
I start at the Iggy sw and work all the way to the coils but since problem is intermittent, so, it's hard to find.
Edit; oh, nope.I don't use E-start.
 
Don't just unplug the R/W wire coming out of the solenoid. That would leave the safety relay still in the system and the problem would still be there if it's the issue. Unplug the whole safety relay.
 
Just a thought. Check and make sure the condensers are grounded well. A problem with their ground would affect both cylinders. Also cause weak or erratic spark. Just a thought.
 
5T, I know, but didn't see your post, was riding! :) With the R/W unplugged, It isolated the coils R/W power wire. I took a round robin, came back and it fired right up twice. Proves nothing . I let it heat soak about 8 to 10 minutes. Went out and it fired right up. Put a timing light on it and it was dead on and for giggles, pulled the covers and checked the advance unit, verified it was not stuck full, Who knows? So, working fine so far and the mix, I think, is great with the peashooters. We'll see. ( I ordered a little min LED 12 volt bulb. Gona wire it in just in case the Yam is trying to trick f**k me!
Thanks for the Input 5T.
Oh, I noticed when I rode in I had a tapping noise. Sounded like a lifter loosened up. Just started it up again. Tapping is not there now. Will have to watch that. Also, a drop of oil on the ground! Athena green gasket, starter area, could be OilyBaba and the 40 leaks!
 
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The more I think about this, the more I think it's a loose connection somewhere. We all know these bikes vibrate. The largest amplitude of that vibe is at idle. If a connection is gonna open, idle would be my guess as to when the odds are greatest.
 
The more I think about this, the more I think it's a loose connection somewhere. We all know these bikes vibrate. The largest amplitude of that vibe is at idle. If a connection is gonna open, idle would be my guess as to when the odds are greatest.

Yep, Jim, I gave that a lot of thought. That's why I want the led tale, tale light for the coil circuit. ( I tried to get the Brother-in-law to stick his finger in the end of a spark plug wire, but the big, bad, Marine wouldn't do it! Go figure! :laugh: Like Pres Bush.. Can't fool him. He's been fooled before!
 
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