The International CBX Owners Association

Went for a ride with my son tonight and both bikes ran great. We stopped for some pics and on the way back mine started to run crappy....popping and farting at times and I could tell that at times I was down a cylinder or two. This has happened the last 3 times I've gone out and think it's a coil going bad when it gets warm...just guessing.
My question is what can I do to test the coils and is there a go to aftermarket replacement one, and or one to stay away from?

My bet is a spark unit is going bad - classic symptom. OK when cold, lose two cylinders when hot. Feel which two pipes are cooler when you stop and you'll know which unit is bad, but if it's an early model, doesn't matter, very hard to replace individual units. This failure is far mor common than a coil failure.

Dave

Dave, thanks for the reply. Is there a way to test which item is faulty, I'd rather be able to isolate which unit is bad before firing the parts cannon at it...LOL

You are working on an early model, I think? If so, all three spark units are one assembly, and as I said, it's very hard to replace just one of the three. There are used stock ones out there or a couple of aftermarket ones. But see if you are indeed losing 2 cylinders by feeling which pipes are cooler after a ride where it's acted up. No test for the spark units otherwise.

Dave

Well....It was so nice here yesterday that we had to go for a ride and decided to go out until it starts running like crap then head back. We were out for at least 2 hours and it never missed a beat once.....quite satisfying actually, but I'm wondering why it would run like crap after 40 min one day then run like a charm the next time out. Maybe those original spark units heard I ordered some new ones and decided they better shape up...LOL

That's the way they go - work for a while, then quit. Heat has a lot to do with it.

Dave

As Dave said -- heat. Ever notice on the prolinks that the spark units are positioned, essentially, at the air intake for the carbs.