Got me stumped?????

[Czekus21]

Usually, when it comes to mechanics or elect, I can figure it out. May take a little time but usually it's a done deal. Here's the deal. MIYAMI (79sf) has developed a temper tantrum that I can't figure out. She runs great but every now and agian ( intermittinly ) after I shut her down, when I go to fire her up, She dosn't want to start. No spark. I let her sit for awhile then she fires right up. The problem is getting worse now, about evry 3-4 time of shutting her down she doesn't what to start. I've checked the pick-up coils, the ignition coils, the nuetral switch, fuses, just about every wire on her, Everything checks out A-O-K. Could this be an early indication that the brain box is going bad? Any ideas mabee what else to check? or what else to go back and recheck? The other day she did this to me, just turned over. Cranked on it for about 15 sec. nothing. Waited long enough to smoke a smoke, Tried it agian. Cranked on her about 20 sec. She gave out a loud pop back fire through the left exhaust ( almost like a gun shot ) and fired right up. Could this mabee be a carb problem? if so, why would it cauz me to not get spark at the plugs? Combo probs mabee??

[chevy45412001]

coils

coils, did you check them while having the problem?

[randy]

Czekus21,

Chances are your brain box is not going bad, but the solder joints inside may be corroded. That's the most common problem with the boxes. You might also check the connections at the ballast resistor, since it's common to both coils. Good luck.

Randy

[Ken Talbot]

I would suspect the coils. When you stop, a lot of heat comes up off the motor and the coils are right in the path.

[Pat Kelly]

Mine does that occasionally (2-3 times since I got it 3 years ago). For me it's the bad kill switch on the handlebar (by the trottle).

[Geezer]

Check the pick up coils. Odds are one oe both have the wires breaking off.

Geezer

[Hepcat]

I just finished a troubleshooting nightmare myself...I was working on an XJ and I don't know if the XS has the same safety circuit. For me it was a relay problem. The Sidestand relay (Yeah, I know, XS's don't have Sidestand Switches) went bad. It was tied into the ignition circuit and the relay would not open and was grounding out the ignition. Do XS's have a safety circuit like XJs? It's all tied into the neutral sensor, tipover switch, and, I believe even the kill switch.

If you've got an ignition relay, try unplugging it and see if that makes a difference...

Just my 2 cents...

[randy]

One more thing. Check the tip-over switch. Mostly overlooked, it shorts out the ignition box when the bike lean angle exceeds 60 degrees .

This is how it works. it's completely mechanical, with a metal ring that slides to and fro on a curved metal loop. Most of the center of the loop is insulated, but when the ring slides far enough left or right, corresponding to your lean angle, it makes contact and cuts the ignition.

It's possible that your switch has a bald spot in the slider causing it to short out intermittently, or the ring is binding. This may be why it only happens sometimes, like when you park using the sidestand, jerking the bike sideways? Just unplug and try to start without it. You can even throw it away, you don't need it.

Its located under the tank just forward of the Rectifier / Regulator. It's called officially, the Emergency Stop Switch Assembly.

Hope this helps.

randy

[Czekus21]

GOOD NEWS !!!! Yeeee... Haaaaa.....
It was the " Tip Over Switch " cut one feed wire at the switch and as I said Yeee.... Haaaa...Bike runs and starts fine now. Thanks for all the tips.