FJ 1100 MINI SAND RAIL AWESOMENESS

[Tuneforkfreak]

Read this and it will give some understanding of how and why it functions. https://en.wikipedia.org/wiki/Capacitor_discharge_ignition

[HUMMUH]

So if I read that right in order for it to spark it's stops sending power to the coils therefore letting the energy that is built up to discharge and creating the spark?

[Tuneforkfreak]

Yes I believe so, I'm not a master in the theory but something has to tell the coils when to discharge.  You have an ignition cover on the left side case, I'd suggest you remove that cover and have a look inside. I'll throw my two cents in now and tell you what I observed. The P/O of that rail ran the shit out of it, the bald rear tires and the video of him doing donuts was a tell tale. Not that I'm against having fun but the FJ engine requires air moving over it to cool it down (That s why Yamaha designed those FJ scoops to get air onto the inner cylinder heads) Sure the guy had an open area in front of the engine but when you spin in circles at 7000 RPM all day that becomes irrelevant really fast.  Heat is the enemy of electronics, there are wires, glue, plastic, magnets and other things in that housing that are only designed take so much heat before they deteriorate ( A magnets main enemy is heat). Id investigate in there and pull some OHMS reading on that unit and make sure its within tolerance. When you get it going I'd suggest a strong fan with a shroud to cool those heads. When you see smoke bellowing up off the engine like I did after the donut session that's not a good sign for an air cooled engine. Front brakes would be nice too. Its a pretty cool little project, I can see why you want to get it going.

[fj1289]

OK - since it sounds like you are using the Yamaha wiring harness, lets do a little troubleshooting on that first before jumping into the deep end and starting to rewire things. 

Have a look starting at page 6-27 (pdf page 230) for the section on the ignition system.  Obviously the placement of things on the sand rail will be different than on the bike, but you at least will know what you are looking for.   Read thru the whole section on the ignition system before you start into it.  Page 6-31 (pdf page 234) in the GYSM has the system description (after the troubleshooting section!) Then it shows how to check the various components. 

With the setup you have, I really think you are going to be better off working with the stock harness - at least until you get things figured out.  It won't matter how its wired up if you've got a bad component somewhere!