Igniter failure - why they fail!

[Bill__Woods]

Hello,
I was reading about the guy that fixes the TCI units for viragos. I am interested to see why the xs ignitors fail. i went to Devry for electronics and should be able to repair these boxes. I am looking for an igniter or two (non-working) that i can examine to find the cause of the failure. I am mainly interested in the 1981 xs 4RO- type boxes. The reason being these are the only ones i can dynamically test with my bike and my portable labscope. I can hook up the labscope and record as i ride. If anyone has some known bad boxes they would like to donate or sell let me know. If/when I find the problem and parts i will write a detailed repair procedure with pictures that i will submit/donate to the XS11 team. The ignition box problem is going to be much worse as the bikes get older. I may be able to build completely new ciruit boards. I have software that allows me to build & test electonic circuits on my PC. let me know if you can help.

[Mike Hart]

Bill I had one fail years ago - I was on the freeway on-ramp and all of a sudden running on two cylinders, what a place for that to happen!

Took me a while to eliminate everything else as the prob, and when I finally (carefully) opened the CDI and looked closely at it, one of the power transistors appeared to have no solder on one leg! Apparently there had been just a bit, but it oxidized or something? Dab of solder, good as new.

BUT, I noticed when I was in there, none of the parts had ID of any kind on them. I know that wouldn't be more than a bump in the road to a good elec-tech...

I expect you might find power xsistors fail, maybe even small components. As to what those DIPs are, good luck! If a custom IC fails, well, SOL.