xs500 no spark.

[Jordan Mohawk Missiaen]

Hi Everyone,

I rode my '76 xs500 almost every day last summer, and I didn't stop riding unti december 1st 2009 (thats quite a feat for wisconsin!). All through the winter (december - february) I would start the bike up and let it run for a while, every couple of weeks. Usually the battery was dead, and I would kick it a couple of times and it would fire right up. The most recent time I started it was about 3 weeks ago, and it ran like a champ. Well I started to get the itch to ride again since it's beginning to get warm again, in order to do so I needed to replace the chain, and front and rear sprockets, they were pretty worn from the previous owner (they might have been the originals). So I replaced the chain and sprockets, I also removed the exhaust to clean it up a bit, I put everything back together today, and tried to start it up, it had a dead battery again, no biggie, just kick start it right? Wrong. It wouldnt fire. I tried jump starting it with my car and still nothing. So I start checking things...good fuel flow, clean air filters...but it seems that there is only a spark sometimes. I have a spark tester and the left cylinder seemed to fire occasionally, while the right cylinder didn't fire at all. So my question is, how could this happen after having it running only a few weeks earlier. Did my coils just decide to die today because it was 50+ and sunny? Anyway, they are the original coils, and I was wondering what the procedure is to test them. If I'm not getting a spark, I assume that means there it's the coil, or the wiring leading up to it. Is there certain voltage/amperage I should be checking for? Also, are these coils known for just dying...or am I even looking in the right place.

Any help on this frustrating subject would be wonderful.

Thanks.

One more thing. If the coils are indeed bad, can I replace them with just any old coils from JCWhitney or old bike barn, or is there specific ones for my bike?

[cegan09]

Sounds just like my bike, nice day comes along, and guess what, there is a problem.

I'll have to read through my manual and find the procedure for testing everything, but if no one else beats me to it i'll try and have answers later today. I replaced my coils and wires with ones from Mikesxs.net, and got new plug caps from a local yamaha dealer.