please help

[yz80nbeast]

i have an xr70 and a bolt broke in the head while putting on the muffler so i rode it like that for a whlie(with one bolt) till the leaking air started to get annoying so my friend told me he had an extra head laying around so we took mine off and switched the valves and did the timing and the bike started and shut rite off, so we tried kicking it again and noticed it lost the compression, so we did the whole procedure over again and it was back to normal kicked it started and the carb idle was way to high and i shut it off and we tried starting it again and the slide in the carb was stuck i notcied when trying to give it some gas so i changed the slide and fixed that problem, then i tried to start it again and it lost compression, so we are about to do the whole procedure again. can anyone tell me what the problem could be(we have done this to my friends bike when he bent his intake valve what could be the problem here) :bang:

 

[Jasle]

Holy no punctuation batman. lets see if we can get these in order...

>

i have an xr70 and a bolt broke in the >head while putting on the muffler so i rode it like that for a >whlie(with one bolt)

Bad idea...quick way to burn a valve!

>till the leaking air started to get annoying so my friend told >me he had an extra head laying around so we took mine off >and switched the valves and did the timing and the bike >started and shut rite off,

OK did you use a new head gasket? hopefully yes! but with some copper spray at minumum if not...

Proper torque specs?

>so we tried kicking it again and noticed it lost the >compression, so we did the whole procedure over again and >it was back to normal

OK what changed then? how did this fix the problem?

>kicked it started and the carb idle was way to high and i >shut it off and we tried starting it again and the slide in the >carb was stuck i notcied when trying to give it some gas so i >changed the slide and fixed that problem,

cool but useless information for the situation glad you now know to make sure the slide is lined up.

>then i tried to start it again and it lost compression, so we >are about to do the whole procedure again. can anyone tell >me what the problem could be(we have done this to my >friends bike when he bent his intake valve what could be the >problem here) :bang:

I'm betting you are leaking compression at the head gasket if you've resued it twice. break down and get a new one.

Or timing is actually off

Yes a bent valve could cause no compression but you should notice it open when the head is off. if they close then thats not it.

 

[yz80nbeast]

well we put it back together again, and it didnt have much compression but it started by puring some oil down the intake manifold and it started right up and i let it run for about 5mins straight and then we put it all together and it had its normal amount of compression and then i rode it today and the gears shifted smoother and idled rough put eventually smoothend it self out, and felt a little faster. but thanks guys for the advice.