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HEY GUYS, so i have taken my head gasket off put a new one on the engine has been put back in and once turning it over it started backfiring out the exhaust and inlet i got it running but it started on 2 cylinders which being 3 and 4 but 1 and 2 were not firing have any of u got any ideas bcos most people i have asked say it is the timing but i would put my life on that it isnt, if u guys have got any ideas plz let me no a.s.a.p cheers.

did you put the firing order back in the correct order and put the connections back to the coils properly (if you removed the connections into the coils from the wiring loom).

I would think its worth a check to remove the rocker cover and the timing cover and turn it over by hand (remove the spark plugs) and make sure the timing is absolutely spot on. Its a pain in the butt to see the inlet cam timing mark, but you should be able to do it when the timing marks are pointing towards each other too...

i can only think if its not the timing it has something to do with the firing order, but if oyu have put the HT leads back properly in the correct order and its firing on 1 and 2 they use different coils anyway....

I would go for leads as well been there mate

Looked stupid at the time as well changed them over fired up fine

Good luck

Sloweracing going HRC

so do the timing marks piont towards eachother in the middle or away from eachother on inlet and exhaust, bcos i have got my timing marks pionting away from eachother closer to the head. and do you bend the valves on these bikes if the timing is out!

timing marks face away from each other, in the way you have them, the inlet mark is on/points to the inlet side and the exhaust mark points/is on exhaust side, so long as you timed it up this way off the crank at TDC.

Depends how many teeth out you are to if you bend valves or not. Always turn the engine over by hand once you have refitted the cams with the spark plugs out (makes it alot easier to turn the engine over) and also how i know the timing marks point towards each other when the tdc marker has gone round the other way on the crank.

Check the HT lead connection like slowerracing says as well, as the leads can come away from the cap.

right ok, i have already pulled them out b4 when taking the plugs out so i have glued them back in so defin int those i have checked everything the only thing left is timing so i will have to drop the engine again to time it up wont i cos am gona take the chain off and start again or can u pivot the engine on the back bolt so the engine swings down.

cant you use a mirror to the see the inlet cam sprocket face?

i never dropped my engine to replace cam chain or head gasket but cant remember how i did it tho

cant you use a mirror to the see the inlet cam sprocket face?

You can use a mirror but the cam sprockets have timing marks on both faces so visibility shouldnt be too much of an issue.

Jackson wrote:

cant you use a mirror to the see the inlet cam sprocket face?

You can use a mirror but the cam sprockets have timing marks on both faces so visibility shouldnt be too much of an issue.

why are people dropping the engine to do this job then? Im slightly confused

Its easier to work on from what i understand, plus you i dont think you can take the head off without dropping the engine because the frame gets in the way.

i did , i did. gimme a gold star

you can get the head off with the engine still in the frame, ive done 2 gaskets this way, but it is a little restrictive when putting it back together as youve gotta get the chain guides in which is fiddly with the frame.

It would be a lot easier with the engine off the frame, but it just depends if you've got the extra time time drop it then put it back in. I guess its just preference in the end