xr80 wont start

[zeppelin]

okay im trying to fix my little brothers old bike so that we can sell it, it hasnt been ridin in about a year and a half, but it ran when we put it up, in the last couple of weeks we have been tring to get it running and it wont cooperate. it has excelent spark, i cleaned out the carb and it is getting fuel i drained the old gas out and put in fresh stuff. i check for compression and it seems good, i ve done almost everything i know to do and it still wont start any ideas

[AtvMxRider]

Have you put a new plug in it?

[zeppelin]

yes, and i have tried different heat ranges too :(

[zeppelin]

i have also tried push starting it in 3rd gear , and it will only give a backfire everynow and then, wilkin where are you lol

[AtvMxRider]

You sure the carb is completely clean?

[crewworrior]

put a little gas down the spark plug hole and put the plug back in then try it if it tries to start then your carb isnt completely clean

[zeppelin]

Originally posted by AtvMxRider
You sure the carb is completely clean?
Originally posted by crewworrior
put a little gas down the spark plug hole and put the plug back in then try it if it tries to start then your carb isnt completely clean

ive cean the carb acouple of times so yeah its pretty clean and ive shot some starter fluid down the spark plug hole and it didnt help

[zeppelin]

i know some of the geniuses on this site can figure this out, bwamos ?

[AtvMxRider]

Have you checked the kill switch?

[crewworrior]

IF this thing is a 4 stroke one of your valves may be stuck open that will not let it start

[zeppelin]

it is getting spark so it isnt anything electrical ( unless some how it it out of timing maybe :confused: ) yes it is a four stroke but therte is nothing wrong with the valves cause it has compression.

[AtvMxRider]

Originally posted by zeppelin
it is getting spark so it isnt anything electrical ( unless some how it it out of timing maybe :confused: ) yes it is a four stroke but therte is nothing wrong with the valves cause it has compression.

It could have compression but not enough to start it if the valves are worn or stuck

[crewworrior]

the only thing i can think of is, it might be out of time, or the valves need adjusting.it really sounds like the valves because you said it tried to start but just wouldnt. i worked on a 3-wheeler for a man who had that problem and the nut on the valve adjustment screw came loose just enough that it lost alot of power and he couldnt get it started back up. hope this helps

[zeppelin]

i'll check the valves tomorrow, i dnt see haw the could have gotten messed up while the bike was sitting but im willing to try anything at this point

[crewworrior]

it may not be that, but thats the only thing that i could think of because, if you have spark fuel and air that thing should run

[zeppelin]

any othger ideas before i rip the head open ( i really dont feel like opening up another motor right now i have 2 others i still need to finish)

[crewworrior]

i think there should be a cover on top of the head that you take off to adjust the valves. you should be able to see the rocker arms from there to see if theres any play when the valve is shut

[Dave J.]

What year is it? dose it have a cdi? or points. If it has points I would check the points and run a point file through them. Also you might wan't to check the flywheel to make sure that the spring advance is working and not stuck from sitting. That would make it not want to start but will still give you a spark. We have a couple xr 75's and 80's that sit around for a couple of years at a time and thats what we have to do if they don't fire. Good luck hope this helps.

[Rich250RRacer]

Originally posted by Dave J.
What year is it? dose it have a cdi? or points. If it has points I would check the points and run a point file through them. Also you might wan't to check the flywheel to make sure that the spring advance is working and not stuck from sitting. That would make it not want to start but will still give you a spark. We have a couple xr 75's and 80's that sit around for a couple of years at a time and thats what we have to do if they don't fire. Good luck hope this helps.

Finally, somebody asked what year it is. You beat me to it. If it is older than 92 then it should be points.

[zeppelin]

ots either an 01 or an 02, co it has the csi, but you can tell just by looking at it that not much of the motor has changed in a looooong time. i'm going to do what dave J said, and i guess i'll check the valves tooo while im at it and let yalll know how everything goes