97 RM250 wont start

[cbfatm]

Well my 97 RM250 won't start, I bought it not running, it has good compression (145 pound) has good spark, is getting fuel, carby has been cleaned out, reeds have been checked, fresh fuel put in, new plug, everything seems ok but it just doesn't even try to want to start. Tried push starting, nothing. Each time I kick it about 5 times pull the plug and it would be wet, clean it up and check spark, put it back in and nothing. Not even a backfire. I've tried nothing and I'm all out of ideas.....

Thanks for your help

 

[psustang89]

You could try disconnecting the kill switch to eliminate that variable. It should just unplug along the main frame rail under the tank.

 

[Kevin003]

It almost sounds like your CDI box is out. Another thing disconnect your kill switch just to make sure its not stuck on.

How does your plug look when you pull it out? Is it dripping black? white? brownish? Maybe your bike is fouling out the plug before it even fires. If this is true you need to go down a few sizes on your main jet.

 

[kimoajaj]

I assume that you have , but the first thing you do is to get a new sparkplug. Even if there is a spark when you have the plug out, it might not be there when it`s put in the head.

if your engine sucks false air from somewhere, it can be a bitch to start and if it`s bad it wount run at all.

Check the seal behind your flywheel, for all you know it could have jumped out and is just spinning on your crank. The same goes for the right side seal (on the clutch side), however it`s a little bit tougher to check, especially if the engine isn`t running at all.

If the right side seal is busted then your it will suck in gear oil from the transmission and run like a bitch and foul plugs/smoke alot. But since it isn`t running at all, it`s hard to tell.

When I don`t get engines to start, and there is compression, I often poor a tiny amount of gas directly into the cylinder through the spark plug hole, then I put the plug back in as fast as I can, and then I crank it. If you do, I`m sure it will fire some how, as long as your spark plug makes a spark.

Try a new sparkplug, if there`s no difference then you will have to use the evaluation method, checking everything step by step. Check the air/oil seals on the crank, check inlet rubber for cracks etc. , check reeds, even if your bike is jetted wrong, it will start, but check the carb for clogged jets/water, then check the ignition system, the best thing is probably to remove the electrical components from your bike and have a dealer measure them?.

Good luck:)

 

[sick 96 250]

your floats are most likely out of adjustment if the plug is getting wet without it even starting. They should be set at about 16mm. With the carb upside down and the floats seated they should basically be parrallel to the float bowl ( straight across). And for what its worth you should be getting around 220psi with that year RM on compression so I would also say your top end could be worn out and your getting blow-by with the fuel and its not allowing it to start.

 

[cbfatm]

220psi???? Geeez never heard of that before I thought the max was something like 180

The kill switch is working because the bike is sparking. I tried putting fuel down the barrel, made no difference. It already has heaps of compression, I took off the footpeg to save busting my foot on it everytime since I had to kick it so hard.

Besides, I have had bikes with close to no compression and they still started.

 

[sick 96 250]

isnt the footpeg what stops the kicker from slamming into you clutch case? Every 250 I have owned with a good top end has been well over the 200psi mark. My 99 RM250 now is on its second season with a top end and i'm at 216psi. Check your float levels then, if the plugs wet but your not getting it to fire up something wet fouling it, its getting to wet for the spark to be created.

 

[cbfatm]

I think the floats are straight. Anything else, it doesn't even cough

 

[j32]

starting fluid in the spark plug hole-- a little,not a hole can
i had to do that with my 500 before ,then see how it runs!!

 

[jj canuck]

i had a hard time starting my 94 i bought a new cdi and had spark but my timing was way off, mabey try advancing your stator plate? it worked for me!!

 

[kx125412]

Im pretty sure the top ends just worn right out. Spend the hundred bucks on a new piston kit and the compression should rise right back up to around the 200 psi mark. Although the compression is low it should start, but not easily. First things first, replace the top end and then go from there.

 

[jason33]

check the pilot jet again clean it
- he has good spark guys
push starting it would have worked even if the seal was bad