yzf no power to coils

[russllbyrd]

Ok so im new here to the yzf forum. I have a four wheeler that I had installed a 94 fzr 600 engine on. Ran great, but I ended up breaking a tooth off of 1st and 5th gear. So I went and bought another fzr engine off of craigslist to replace it with for a good price. Once I brought it home I noticed that it wasn't an fzr motor, but rather a yzf. No big deal right? All the same mounting points it bolted right in. Problem is the wiring harness. The yzf came with the harness, cdi, coils, and carbs. But for some reason I can't seem to get any power to the coils. I'm unsure as to what the problem is. I can put my fzr harness, cdi and coils on it and I get fire, but obviously the timing is different on the two engines. So why can't I get power to the coils with the yzf harness?

[DonTZ125]

Not sure how you have the wires hooked up, but the YZF engine, like the FZR engine, is TCI, not CDI. You should have +12v from the key switch to the Ignition fuse to the Kill switch to the coils; with the switches on but the engine off, you should have +12v on the Red/Black wires at the coil. You may have to do some splicing.

[russllbyrd]

I'm about to go crazy with this thing. I've been splicing, jumping, and testing wires all day. Ive got 12v+ to and out of the key switch and the run/stop switch. I've got 12v+ to the fuel pump. I've got the side stand and neutral switch bypassed. Still no power to the coils. I've tried running 12v+ straight to the coils but I still don't get any spark out of it. I've completely unwrapped my harness and I can't find any broken or pinched wires. Is there anyway to wire the yzf icu to the fzr wiring harness?

[DonTZ125]

Welllll .... Yes, I can make an adaptor for you (it would take a while; I don't have all the YZF connectors in stock yet), or you could clip and splice the YZF connectors in yourself. It's not hard, but it is non-trivial. You'll need to have wiring diagrams for both bikes, and a fair deal of patience.

I'm still baffled by this no-power at the coils ... You have 12v out of the kill switch - follow the wires. Where does the voltage stop? The R/B wire should be a straight run from the KS to the coils and the TCI. The sidestand, clutch, and neutral switches are irrelevant as far as getting voltage TO the coils; they only come into play when you're cranking or running. A static 'ON' condition doesn't involve the safety switches.

Do you have the TCI box plugged in at this point? If the coil drivers are fried ON, they would be grounding the coils, reducing the apparent voltage at the coils. Are the coils hot?