No Spark!

I took my bike apart and rebuilt the engines top end over the last winter. After I got it back together It was starting but not idling or running. It would pop and back fire and such. After messing with it for a while it suddenly lost fire and I cant get it back. I was jumping it off of a car (which I find is a big no no). I have checked the items in the haynes repair manual and everything seems to be in line but no luck. I am getting frustrated enough with this to haul it off. I have no available donor TCI or parts. Any Suggestions would be greatly appreciated. Also I am in the Omaha NE if anyone is around.

 

You can jump a battery. You need to be careful not to earth the positive. The problems start if you jump the bike with the car running or connect the battery with the bikes ignition on.

Safe method is to use a battery that is out of the car with the bikes ignition off when you connect the leads.

If you have spiked the ignition module it can be repaired see:

http://members.tripod.com/dave_jack/id41.htm

Note the bit at the bottom of the page about the zenner diode.

Check main fuse (by headlight)?

Ignition lights on dash work?

Original problem:

Valve timing correct?

Did you take the carbs apart?

New plugs?

Coils at spec?

 

Hey! Another Omahaian. Welcome to XJBikes!

I'd start by taking your plugs out, holding them against the head and making sure you have good spark across the whole RPM range.

I had a similar problem recently, and it turned out to be a bad coil. I replaced them with some Dyna DC1-1's and the thing runs great.

 

I have no spark anywhere. I think it's probly the tci unit but I was seeing if you guys had any cheaper ideas

 

If you have a buddy who knows how to weild a soldering iron (or give it a go yourself?) they should be able to check the TCI with the info I provided in the link. That diode can be fried jump starting but can be easily and cheaply replaced (if that's the (only) problem).

Double check a wire has not been damaged or not plugged in correctly.

Starter motor turns over OK?
Battery fully charged (these motors will turn over fine on a flat battery but you will get no spark)?
Tested the coils with a test meter?
Aleternator brushes OK? (long shot)
Safety relay or associated component (sidestand switch, clutch switch, tilt cut off switch)?
Loose connection?
Faulty (bit you put the key in) ignition switch ?

The only way to test a TCI for sure is to try a known good unit.

 

no luck, guess i'm gonna have to take it in...

 

To all who tried to help thank you tremendously. I have found the problem and I can't stress strongly enough... Always check your wiring harnesses, I checked them all 5 times before I found it and I am now proud to scream at the top of my lungs "ITS ALIVE!"