View Full Version : yz80
gday all i got a problem with my 84 yz80 she hasent run for a good couple of years now i bought it of a bloke not goin when i try 2 start it will only run for about 30 seconds and its only just tickin over iv tryed fresh fuel new plug and cleaning out the carbie but nothin works it semes to be geting fuel and has good spark but when i take the spark plug out it has alot of black oil on it im runing the fuel mix at 30:1 when u try to open the throtle it just dies could it be that because it hasent run for so long the bore is just gumed up with alot of oil and just needs to be cleaned out ? it has good compresion any help would be apriciated because my legs geting real sore kickin it and im get real fustrated thanxs mick
04-17-2007, 11:11 AM
Well Mick it could be a number of issues causing the problem. An old 80 like that I'd suspect rings though you say compression is okay you really need to use a guage and get the actual figure and check that against the specs. It don't take much of a loss to do in such a small bore. Make sure your plug is the correct heat range and the plug wire might be bad. Be certain the oil you're using is the right type. It could be your float is out of adjustment or your fuel line is partially clogged or kinked (fuel starvation) Lot's of other possibilities, you might want to consult a Yamaha mechanic and cover his palms with a bit of silver as a last resort. Most MX riders using YZ80's know all the symptoms.
04-17-2007, 03:21 PM
Random things to check:
Spark plug gap?
Carbon buildup on the cylinder head?
All I have right now, it's been a while since I've had a Yammer Hammer two stroke.
04-18-2007, 05:05 PM
I had a similar problem and Mine is a 2000. You should run it more like 32:1 to get more fire, and defenetly check the Gap in the spark.
12-12-2007, 07:21 PM
after all these months of kicking... how's it going mate?
what was the problem?
still aint got her going lost intrest workin on me klx now
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