RM125 starting problems

[Erickmxlvr91]

I have a 1980 RM125, which has new rings in it. I have started it up a few times over the past few days, and it has ran perfect. Then, i go to start it up today, and, it fired a couple of times, and after that it will not fire at all. It has spark(maybe not enough?), and has a wet plug when i pull it. I cannot figure out why it is not igniting if there is spark, could it be an insufficent gap or fouled plug? Or could it be something with the ignition or carberator or compression? Also does anyone know that spark plug gap these are supposed to have?
Any suggestions would help.
Thanks

 

[j32]

what does it run like when running?
might need a new needle and seat for the floats,and /or carb cleaned
check the floats to see if there working propperly,some older floats can get leaks and fill up with fuel,check the reeds make sure there not warped,or broken
purchase a clymer manuel for it you will be happy there only like 25-30.00 and well worth it,check local book store ,and bike shop
hope this helps

 

[Erickmxlvr91]

thats just the thing, it ran perfectly fine the last few times ive started it, and then i go to start it yesterday, and it fires maybe 5 times, and will not fire again at all no matter how hard i kick or if the choke is on or off. I tried priming with gas under plug (even though the plug is wet), but i cannot figure out why it would not be running if it has spark, and gas is getting into the combustion chamber.

 

[mxmatthew]

you say the plug is wet, could it be fouling plugs?

 

[Erickmxlvr91]

yes, thats what i thought so i got a new plug today, and that did not seem to help, so i took apart the whole carb and cleaned it and it still did not want to fire, and then i got on it and i found a way to ease the throttle open while kicking and thats the only way it seems to start sometimes. It never reqired the special throttle modultion before. And, when i ride it around and brake hard, it seems to die on me and require that special throttle modulation while starting, but other times, it will just start up like a normal 2 stroke.... really weird but i cannot figure out why it is so picky.... does anyone know the spark plug gap these things are supposed to have?
thanks

 

[Rootuser]

Pilot Jet

Check the Pilot Jet.... sounds like something got stuck in it. Are you running an inline fuel filter? Take the carb completely apart and clean it out entirely. If everything was running fine, and then went to hell all at once and so completely, it's usually something drastic, like a clogged jet, clogged air-filter, fouled plug, etc. The fact you say you can mess with throttle positioning and get it to work makes it pretty obvious that is has to do with fuel delivery. One more thing, make sure the needle in the carb-slide didnt slip or get stuck in some strange position.

At least this is where I'd start.


-- Root

 

[Erickmxlvr91]

yea ill try it thx for all the help guys...