TOPIC:

OK, first off, I have a 1978 KZ650SR (d1).

Recently on a ride from work to home I lost a lot of power. Upon closer inspection......I'm loosing spark to plug 2 and 3. Its intermitten, will loose spark on 2-3 while riding, hot or cold or just at idle. My first thought was replace teh coil. Checked the prices.......Any suggestions? Maybe I can check something else that may be causeing the problem? I've had the bike for a year now and it run perfect until now.

Any help or suggestions would be greatly appreciated.


Rich

Check out your ignition coils-found on points plate or electronic ignition plate. Try swapping your coils to see if the prob moves to 1 & 4. Otherwise I'd look into the ignition coils.

OK, seems to be the coil for 2 and 3. Any way to fix this or when they go they go? Also, any suggestions on a place to buy a new one? Limited funds.

Try Z1 Enterprises, the owner is on this forum often. He'll talk to you if you phone him too.
Ask him about this coil, www.z1enterprises.com/detail.aspx?ID=2857

Otherwise maybe a cheaper coil can be bought on ebay.

May not be a bad coil.

Has an ohm check been done on both primary and secondary windings on BOTH coils.

Are the ohm readings for left coil comparable with readings for right coil?

Often it's something more simple, such as a loose or faulty connection or intermittant wiring problem in the wiring from battery to coil. Or old deteriorated spark plug wires or caps.

Checking the cheap stuff first.

no way of fixing a bad coil, most of the time its internal, you can find them used at a bone yard or flebay, but you can get one that could be bad also or it can die at any time. For the time and effort replace both coils, and also look at doing the WG coil mod

del

I had the same problem with my bike years ago. I pulle the tank and looked at my coils- both had cracked plastic bodies. I found a pair off a KZ550 on Ebay for like 15 bucks. Best money I ever spent. Also, these coils allow the use of new spark wires as my old ones were soldered in.

Check Ebay. Maybe you can get away with a cheap replacement?