BIKE UPDATE..

Cleaned the pick up, re-checked all the wiring & swapped the plugs over again. I've got spark again now but it doesnt seem to want to fire up, its trying a little but not overly convinced it gona start.

I tried to swap the rotors but cudnt get either undone, so it maybe the rotor stopping it from starting. The only thing i dont get is that if the engine is from a J reg gixa the same as mine then why wont the rotor work on mine and why is it different?? the the same age & both import so not sure why it wont work. I will have to hope the one that on there will do the job for now tho.

Is there anything else i can do to help it fire up easier?? and is it more likely to start off the button or bumping it??

only thing you can do is swap the cdi with one from a later bike or change the rotor. If the rotor is different then it won't work without swapping it

the different cdi and rotor was introduced for the 53hp restriction. Where early bikes were 59hp out of the box

oh rite.

I gave it another try and its trying to fire but it sounds like its sparking at the wrong time. Kinda sounds like its firing on the left over fuel after the blow stroke rather than before. What would cause that & how can i solve it??

Im not sure how im going to get the rotor off, i can get the one off the new engine but i cant undo the one on my old engine as i have nothing to pin the sprocket still so it just spins, everything i've used so far has just bent!!!

I got no one near by with an airgun so im abit stuck unless i can think of a way to hold that sprocket still DAMN BIKE lol

is the old engine scrap? If so take the head and barrels off and put a bar across under at least two pistons that will lock it to undo it. Its the only way to solve your problem. It will run when you swap it

Yes old engine is buggered so will give that a go 2moro.

If i put the new engine in gear to lock it and undo it, is it likely to bend anything in the engine or put the engine at risk??? i dont really wanna fudge this engine doing it if its a big no no!!

to do this you will need the engine in gear. Someone sitting on the bike and the brakes applied. When undoing the bolt you will also need to shock the bolt free to break the seal of the thread lock. The main thing is shocking the bolt free. After its free there is no resistance. Don't try it without help or it will fall off the stand

It took me all day but i finally got the rotors swapped over :)

She fired up but was only on 3 cylinders so i swapped the plugs back AGAIN lol. It fired straight up on 4 cylinders... took me a few mins to get the idle right as it was straight onto the limiter when i started it which made my neighbour jump lol.

Of course i had to do something stupid.. i kept turning the idle speed down, i got to 4,000 rpm but wudnt go any lower, i kept turning the idle but nothing then had a proper DURRRRR moment... i still had the choke on haha.

Its running perfect now, i rode it 75 miles last nite to visit a friend and not a foot outta place.

On an completely unrelated subject, i do have to ask why cant the goverment make track tyres legal for the road?? Not that i would do anything so naughty as to have a cut slick front nestled between my forks but its so much grippier than a road tyre & have saved me a couple of times coming a tad to fast into a corner & it never slides, bumps or anything so you can have complete confidence in it. As long as its got grooves like a road tyre and it had the same tread depth limit as a road tyre, i dont see the problem... Anyway im rambling lol.

Thanks alot for all your help stripes & mattely, much appreciated :)

Before i forget, i have a race can to go on as the exhaust is abit quiet for my liking at the minute & i need a new filter so thought about wacking in some race filters... anyone know the best make to get and where's the best place to get them???

No probs, why don't you run pirelli diablo supercorsas? Road legal and many club racers use them, i can vouch for them (crash bung touched down at llandow and i stayed on, now that's lean angle!)
Filter wise, k&n do one that fits (not listed for the 76 though) part no SU-7592 . Remember, it will need the carbs setting up correctly preferrably on a dyno.
Well done for keeping at it, most would have given up long ago!

edit: completely wrong part no. now edited lol

glad you sorted it mate. i personally wouldnt use individual filters as you will lose all midrange and they are a pig to set up. but as matt says the k&n filter will give more without sacrificing to much low down.