yet another electrical problem

[magyver]

i have a 1986 xt600 it has an intermitting electrical problem. i can start it up and sometimes go 100 feet or sometimes it goes 5 miles and cuts out and dies. sometimes it recovers and goes some more . i have bypassed the kickstand switch , unhooked the nuteral switch, and disconnected the key and cut off switch going to the cdi box (blue and black wire connectors at cdi box) so i cant shut it off . it starts on seconk kick most of the time. i have ohmed out all the wiring i can get to and all seems to be fine . but none seem to be in the specs i can locate on the net .and havent found a proper wiring schematic for it yet so a lot of guessing is going on here . but this thing is driving me nutty. im up for any ideas or suggestions . thanks

[cyberzar]

could be one of the wires that is broken inside, and with the heat the two parts disconnect. Pull all wires to see if one has an "elastic" feeling. Usually wires problems happen in the front mudguard area.

Another font of problems can be a bad connection (loose or oxydated connector). There is a very comprehensive text here

Motorcycle Electrical Parts (ElectroSport Industries)

Checked all this, you can suppose a CDI problem, check the temperature of CDI unit when the bike goes off, and then try to reproduce the problem moderately heating it with a hair dryer.

[tufty]

Wiring diagrams here : www.xt600.de

Some are in German, some multi-language, but handy none the less.

Intermittent cutout could be a good few things. Busted wires, as cyberzar points out, also dodgy earth connections on the coil, buggerated HT lead, loose plug cap, dodgy ignition connections from the HV side of the alternator, alternator winding insulation breaking down when hot, CDI overheating, iffy solder joints inside the alternator, bad connections on the puser coils, etc. Debugging stuff like this is a long and horrible job. Good luck.

I'd probably start with ensuring the coil earth connection is good, and that the plug cap is properly attached. Also inspect where the HT lead comes out of teh coil, this is subject to a lot of vibration and bending, and the insulation can break down, leading to spark earthing from there (that's easy enough to fix, bathroom sealant)

Simon

[magyver]

i took the wiring harness connections and and checked every one of them last night . had the onm meter hooked up and wiggled and jiggled all the wires and connectors. checked the plug cap and coil , shortened the end of the coil wire. got done fired her right up cold take off and she fell on her face. she wouldnt start . went in and ate , came back out 1/2 hr later and she she fired right up. let her set and warm up and ran for about 1.4 mile and was pushing her back home . 1/2 way there i tried again and she fired . this is getting to be a real tough one. is it possible for a cdi box to fail intermitting like this is doing, in thought if it went it was just bad. what i need is a doner bike to swap some parts on ie ,cdi ,coil. but there aint too many around here.

[juddadredd]

Have a look at your kill switch, I know it sounds funny but open it up and see if it needs cleaning out or greasing and that all the contacts are ok, when I dropped my bike I had the same problem it was a connection problem in the actual switch quick solder later and all is fine now.

[magyver]

i have unhooked the kill switch and key switch they no longer shut the engine off or have anything to do with it running . today i unhooked the battery and tried it again same thing it is limited to the cdi or coil i think but no way to catch them messing up and they aint cheap to try . makes me wana shoot it and burn it but it looks like new and only has 9000 miles on it ,

[juddadredd]

Burn it and tell the insurance it caught on fire while you were driving along, what they don't know won't harm you, and you can get a new bike.

OMG I'm a Drokking Criminal, I didn't mean it honestly

[cyberzar]

Originally Posted by magyver

i have unhooked the kill switch and key switch they no longer shut the engine off or have anything to do with it running . today i unhooked the battery and tried it again same thing it is limited to the cdi or coil i think but no way to catch them messing up and they aint cheap to try . makes me wana shoot it and burn it but it looks like new and only has 9000 miles on it ,

no wonder hyas only 9k miles if it works like you say... seems like a cdi problem, write down the code on CDI and look for a replacement one, you should find one for 50-100 $. Did you already try to heat the CDI with hair dryer?

[CMichaelCRide]

I have had the coil do the same thing when it got hot.

[magyver]

heck ill try anything but it dont seem to be a heat problem , ill try the hair drier tomorow. it can do it stone cold or warm doesnt matter thats what is making this so difficult to track no set time ,pattern or temp seem to set it off. it just does it when it feels like it . heck today i pulled the tank and watered everything down good with the waterhose and she fired right up and made one trip around the barn on the fuel that was in the carb, put the tank back on and she made it half way around and died. pusher her back to the front and she fired right up and made maybe 2 miles before doing it again .

[fward]

i have had electrical problems with my 89 tenere that would make a man cry. Lots. Some problems similar to yours. I would strongly recommend removing the stator cover to have a look. Wires from the stator coil and the pickups are exposed to huge heats. Bad insulation/plain old age of these wires can lead to badly burnt ones or cable/cables intermittenly earthing of the case ( I have had both happen). Every time I had an electrical problem it always ended up being here (never the cdi). I would remove the stator cover and ...

1 - check the wires for damage at the exit point of the casing

2 - remove 3 bolts for stator, 2 bolts for pickups and the 2 cable retaining brackets. Pull away from the case and inspect every wire

3 - Inspect inside of rotor for abbrasive damage and outer surface of the stator coils for same damage. If your stator is banging off the inside of the rotor this will cause intermittent running. ( causes - rotor not bolted on tight enough, crankshaft bearings shot. Try and rock the rotor with your hands while your there. There shouldnt be any movement)

4 - make sure you have the correct ohms readings needed for the ignition coil and the two pick ups and test.

Last thing - when the bike suddenly stops like you describe and doesnt start again - have you then pulled the spark plug lead off, removed the cap and earthed the lead off the engine before kicking over the bike to see if you are getting that big blue spark ?

The stator removal is 10 min job. Tilt the bike against a wall on the offside of the stand side to save you draining the oil.

Wish you all the best - god i know how this feels!

[Walkabout]

Originally Posted by magyver

i have a 1986 xt600 it has an intermitting electrical problem. i can start it up and sometimes go 100 feet or sometimes it goes 5 miles and cuts out and dies. sometimes it recovers and goes some more . i have bypassed the kickstand switch , unhooked the nuteral switch, and disconnected the key and cut off switch going to the cdi box (blue and black wire connectors at cdi box) so i cant shut it off . it starts on seconk kick most of the time. i have ohmed out all the wiring i can get to and all seems to be fine . but none seem to be in the specs i can locate on the net .and havent found a proper wiring schematic for it yet so a lot of guessing is going on here . but this thing is driving me nutty. im up for any ideas or suggestions . thanks

How are you so sure that this is not a case of fuel starvation? (not mentioned here at all).

[magyver]

i eliminated the fuel by carrying a screwdriver and when it died i imediately loosened the fuel drain screw on the bottom of the carb and watched the fuel flow through the clear fuel filter . besides , it doesnt sputter like when its running out of fuel . its an imediate shut off. oh well when i get back today ill pull the sidecover and check the wires and coils. as i cant find a break in any of the external wiring. i didnt gently tug on them to find breaks , i pulled and snatched them like i wanted to pull them apart.with an ohm metre hooked up watching the continuity. and they all held up, so they gota be good . i was with my friend when he bought this bike brand new and i have a lot of miles on my ty following him around .sometimes he let me lead the way to clear the spider webs in the woods.

[yhprum]

When it dies, does it spit back through the carb? Mine did that once at low rpms merging onto the freeway and died immedialtly. Not fun kickstarting in the middle of 5 lanes traffic in 110F heat!

I found it was running too lean.

Steve

[Walkabout]

Originally Posted by magyver

i eliminated the fuel by carrying a screwdriver and when it died i imediately loosened the fuel drain screw on the bottom of the carb and watched the fuel flow through the clear fuel filter . besides , it doesnt sputter like when its running out of fuel . its an imediate shut off. oh well when i get back today ill pull the sidecover and check the wires and coils. as i cant find a break in any of the external wiring. i didnt gently tug on them to find breaks , i pulled and snatched them like i wanted to pull them apart.with an ohm metre hooked up watching the continuity. and they all held up, so they gota be good . i was with my friend when he bought this bike brand new and i have a lot of miles on my ty following him around .sometimes he let me lead the way to clear the spider webs in the woods.

Fair enough, the fuel gets to the float bowl (as per the last post) but does it get through the carb OK? IMO it is worth being sure about the basics of the bike before spending good money on spare parts that may not be the problem.

At least you know the history of the bike, so what has changed recently that could have caused the symptoms you are now getting?
In the past it has helped me when I have "stood back from the whole problem" and re-assessed it from another angle - that's one of the great things about threads like this!

having said that, I agree that hot electrical components can do funny things.

Keep the faith!