COPS on a 1979 XS 650?

[Bill Seward]

I had a 650 twin back in 1976, but don't remember enough details to know if it's possible to convert a '79 to coil sticks as easily as we can with our VMaxes.. Got a buddy with one with probably crapped out coils, just thinking COPS as a possible solution. I'm not sure if the bike has one dual wire coil or 2 separate coils. I would imagine that a single coil setup wouldn't work.

Any ideas?

 

[55nalive]

early had two coils 80 to 83 had one coil 2 wires not sure about cops

 

[Bill Seward]

Seeing that a coil stick is just an ignition coil built into the plug cap, I have to figure that you could simply wire the coil sticks directly to the 2 wires that power the coils. That's all we do with the VMaxes, and it seems to work fine. It probably doesn't matter at all if the voltage drop that triggers the spark in the coil or COP is caused by some little electrical genie in some black box, or a set of points opening. Thinking I'm gonna find out, and will report results..

 

[Traumahawk]

Please do....now I'm curious to see what will happen?

 

[one2dmax]

Yes, it can be done. We even worked with Gannon to get a setup figured out for the Fazer (which uses 2 coils to fire 4 cylinders).

Sean

 

[Bill Seward]

I thought about the dual plug coils, because the Road star has 2 spark plugs per cylinder. I figured to wire the COPS in parallel. They'd both get the 12 volts, then hopefully fire when the TCI dropped the volts to the coils. The 4 cylinder bikes with two coils fired every crank rotation, with the spark as the piston rose on the exhaust stroke being 'wasted', as it was referred to back in the day. My Honda 160 also used the wasted spark design. As long as the bike has a coil with 2 wires, adding coil sticks should be doable, even on a bike like an RD 350.. I'm gonna grab a few sticks on EBay and experiment...

 

[one2dmax]

Wasted spark is correct. It took us 3 tries to get the configuration and ohm loads to work correctly. Not as easy to wire as you might think since the wrong way would kill out a cylinder for whatever reason.

Sean

 

[johnpclynch]

Won't work if the bike has points - they'll burn before you have a chance to turn the motor over (I tried on my xs750)

Electronic ignition only appeared in the 80s on the XS range

 

[Bill Seward]

Would the points burn because of the decreased resistance of a coil stick compared to a full sized coil? I could see that being the reason for the failure... Did the pre-electronic ignition 650s have any kind of control box, or were they just simply points, condenser, and coil?

 

[55nalive]

no box just call 209 533 4346 Michael Morse he can answer all, and sell you a new coil good guy. cal time,

 

[johnpclynch]

Would the points burn because of the decreased resistance of a coil stick compared to a full sized coil? I could see that being the reason for the failure... Did the pre-electronic ignition 650s have any kind of control box, or were they just simply points, condenser, and coil?

It's the coil that will burn - the points sit in the closed position so long that they will over saturate the COP and they quickly overheat. Regular coils are big enough that they don't suffer from this effect