Hello, wiring question

Hello, just joined the site, i'm from the UK, I'm racing a pre diversion/pre seca11 XJ600 (FJ600) In a post classic production class, been running all season with the standard late engine from an 89-92 bike which has the alternator on the left end of the crank, the bike suffers on pickup from corner exit and this stuck on the side of the motor can't help, i've just picked up another early bike (1986) this one has the alternator behind the barrels, i'm going to be swapping this engine into my race bike but here's where i need some help.
There's wiring for the alternator brushes and i don't know where to wire them into, i think they're supposed to go into the loom then the reg/rec unit, there's a four pin plug on the race bike and a 7(i think) pin on the early engine, also i think there's one ignition pick up on the bike but two on the early engine. was hopeing for an easy swap if i can get some pointers on the wiring then maybe it still will be.

Lastly (for now) i took the early bike out for a run and it runs out of steam around 110mph ?, these should go 130-135 on the clock, hopeing it's something to do with the carb diaphrams but any sugestions most welcome.

Thanks in advance.

 

Hi Malc,
Check out these wiring diagrams here.

What is the model of the engine? 4H7, 5G2 etc?

If its close to one of my engines I'll take a look at the plugs for you when its light out.

As far as the running out of steam is concerned...
I'd check the compression first to see how tired the engine is.
Then check the plug colour to see if its running rich or lean etc.
Then check the air filter for blockage.
Then finally pull the carbs out and get into em, using Rick's writeup.

Diaphragms -JBM Industries.
All other Bits - XJ4Ever

 

Thanks for the links, the engines a 51J, not the same as your i think.

I think i've worked out how to wire the brushes but looking into the pickup coils and cdi i can see more problems, i could wire the pickups to work i think but all the other wires in are different for the two different looms, more thinking and staring at wiring diagrams for me i think.

I've checked to carb diaphrams and they seem all ok, could see no splits or holes but bike still only pulls 110, 5th or 6th doesn't matter it won't pull any more. The air filter is new so rules that out, i checked the plugs and 3 were very light, maybe a bit lean, the last #4 was dark brown, maybe a little rich so i think i need to get the carbs off and have a proper look inside, as the bike only has 18000miles and is 26 years old i'd guess it's done a fair bit of standing still for years at a time maybe..

 

I'm assuming you've checked the valve clearances? Compression?

What RPM is it pulling when it's running out of top end?

 

Valve clearances are ok,

Can't remember what revs it was pulling, around 10k in 5th i think, but the needle wasn't going up so not clutch slip if thats what your thinking. Not done comp test as i don't have a tester but the bike pulls as it should (i have other XJ's) just not at the top end.

I'll have the carbs off while i'm sorting the other issue out and try it again after that.