hello, i have a air cooled 1984 250r and we had it running absolutly fine, and the other day we were riding it and it stalled, so i figured we just fouled the plug, i put a new plug in it, didnt start, so we bought it back to the garage and it has spark, it has fuel, and it has compression, but it will not run, i wont even fire on starting fluid, it has spark though, so maybe its grounding out somewhere? not enough spark? i need help please, its been 2 days now ive spent trying to figure out something that is probably so simple, i checked the gas, its fine, im stumped, i took the cdi box off, cleaned all the connections, and grounds, still no difference, help?? thanks kyle

 

i think i may have narrowed it down to 2 things, maybe 3, not enough spark, timing is off, low compression, it still feels like it has alot of compression, but i didnt put a gauge on it, can someone tell me what the compression should be? and what are the possibilities of weak spark? cdi box? stator? and if the timing was off, it should still run with less power correct? any help would be appreciated, thanks kyle

 

i'm not all that up to date on yer model..but..i can almost bet your timming has jumped out....take off your c.d.i cover..then pull out your ignition.yu'll need to unbolt the center contact..once you have that removed, you should be looking at your timming gear,one of the bolts has a---> 0 on top of it..thats your top dead center..their is a mark on the top of the c.d.i cover..they should be aligned,now..unscrew the cap thats on the left side ..just right of your pull starter..once you unscrew that..look inside..and while you pull on the rope..look for a T & F..you will notice a arrow inside that cap..pointing to the center of your enigine..aligine the T..and the arrow..then you have top dead center..once you get all that back in place..rebolt your cam head back on...as i said..it sounds like you jumped timming..but..if this doesn't solve your prob..last but not least..check your battery..yeah..i know..sounds stupid..but..it's always the simplest things we over look...good luck !

 

That sounds like the same thing that happened to me. If you didn't check the compression I'd say that you need new piston + ring. It should only take about 10 min. to pull off the head and check.

 

ha, what do i know, it was just a sheared flywheel key