It Just Stopped Running

[bryantar]

over the last several weeks i been having problems off and on with my 1978 XS 1100. i thought i had it all right today when i took off on an about 45 miles trip to find a birthday present for my wife. ( tomarrow her b-day cant forget). i got about there and the bike acted like it dropped 2 holes or something it would not accelerate but was still running. so i limped on into town. got there got gift. started the bike up and it ran fine. started home and about 20 miles in it started missing agan. i messed with the ignition switch and it would come back to life run about 30 seconds then start missing again. it did this most of the way home. i parked it and tried to start it again and it would not fire.

i pulled off one plug wire and they are not firing. i messed with the switch again and it would try to start but never would. i thought it might be the switch so i removed it and put the wires together to bypass the swtich and it has no fire.

once in awhile it backfires hard thought one of the pipes.

ok, now i am going to sound like someone who knows nothing...
on the motor there is a cover on the right hand side that appeares to house a magnito or somthing. i took the cover off and there is power to the mag (if that is what it is.)

not sure what to do or where to go. i fixed a fuel problem last winter that was an experance. but there are so many wires on this bike i dont even know where to staart... help please.

thank you

[bikerphil]

Read this thread about pick-up coil wires...

http://www.xs11.com/forum/showthread...=&threadid=122

[bryantar]

they wires appear to be ok there.
is there supposed to be power down to the pickup coils?
i traced the wires all the way back up to behind the fuse pannel none of the wires are hot.

[Ken Talbot]

Originally posted by bryantar
they wires appear to be ok there.

Hmm, what do you mean by "appear to be ok"? Were you able to get it running so you could pull and push vigorously on each one of the wires, or did you do the yanking and tugging with them connected to a meter, or did you do a cursory 'visual' while pulling gently and looking for "hourglassing"? We need to know how thorough you've been to this point, so we can point you in the right direction for the next phase.

[bikerphil]

P/U coil specs

Should be 720 ohms + or - 20% at 68F. Make sure you also wiggle the wires down by the pickups while testing. They can break inside the insulation especially under the crimp clamps.

[bryantar]

i went back again and looked at the lead wires on the pickup coil. and checked them with an omh meter. one set checkd out ok, the other set did not even move the meter. i pulled them appart where they were spliced by someone else and then spliced them back together. (need to do a better job when i can buy some parts but they check out ok now on the meter.

the bike starts and runs again now. only road it one block because the temp is like 48 here and i was not wearing the proper cloths for that. i will ride it more tomarrow and see if that fixed it for sure.

would one set being broken make the all four cyl. not fire? or do i have another problem somewhere else?

[bikerphil]

1 bad wire would cause only 2 cylinders to drop out. you might have more than 1 bad wire.