Help brainstorm, KX100 won't run

[ChadInColo]

1997 KX100, my son bought it needing a crank last summer. We got it all put together, he rode it about 20-30 minutes after that, and put it away for the winter. Got it out last weekend, drained the gas, cleaned the carb, fresh gas and spark plug, and it won't run. There is spark, 110 psi compression can smell a little gas on the plug (smells stale though) but not too wet. Wondering if I just need to pull the spark plug and kick it over, clear old gas out of the bottom end, looking for help on what else to check.

 

[Blink-182]

110 psi? thats really really low time for a new topend?, at that kind of compression you have to push start it

 

[2strokerfun]

Well, the top end only has 20-30 minutes and he is measuring psi cold. With a little more time and warmed up, it will likely be higher, if put together right. But he does have to get it running first.

 

[DougRoost]

Is the airfilter clean and airbox unobstructed? The 100psi compression makes me wonder if some small animal didn't get in there and build a nest while in storage.

 

[ChadInColo]

Update

Ok, did some tinkering, pulled electrical connections and cleaned, new spark plug, and now it will start (after some kicking, not first kick) but then acts like it's starving for fuel. I won't run at idle, will run for 15-30 seconds and RPMs will drop until it dies.

I'm thinking maybe check the crank seals (possible I damaged one installing...) I'm going to pull the carb apart again just to make sure none of the jets are plugged (cleaned it once this spring). Any other ideas?

 

[Dylan19302]

when you get it running are you holding the choke up because with my CR 80 you need to hold it for at least 1 minute before it will idle without it. Also is the idle screw set right.

 

[helio lucas]

check the fuel lines and clean up your carb...

 

[VISaki]

speaking of top end rebuild..is it safe to just install new rings if thats all that is required..i mean I have low compression but sleeve is still good and so is piston so what do you think..comes with twin rings around piston so you can say that it really isn't damaged at all.