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I recently worked on an old '79 Suzuki Rm125 after sitting for maybe 3-5 years. I'm pretty sure I washed the carb good. The stator was filled with water... :eek: but i cleaned it out and sanded the connections with fine sand paper.
I got it running, but it will only run on choke... The second you take the choke off, it dies even when it's hot. It also hesitates off the choke when you pull the gas in even the littlest bit. Also, I put in a new spark plug in it (it was listed in the manual), but the spark plug does not give out a fat spark, but it does spark a little. Any help would be great.
 

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Bran, after it dies, pull the plug and see if it's wet. If so, I'd say it's the spark. When the engine revs, it creates more compression. Bad spark plugs or condensor won't fire properly in high compression.
 

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I don't remember if that bike has points or not. I don't remember if my 78 RM250 had them or not. I'm thinking it had a CDI. Try cleaning every connection and where the coil attatches to the frame before buying any parts.

The needing choke on to run means it's running lean. Make sure you have the jets clean (take them out and clean the hole through them and the little holes along the side people often miss with real small wire) and make sure the intake boot has no cracks in it or the gaskets are leaking. You can do that with carb cleaner while the engine is running. Spray cleaner around the intake boot area, if there's a leak the engine RPM will change. Worst case senario is a bad crank seal.

I've had a float bowl vent get plugged up and it needed the choke on to run.

They are a good old vintage motocrosser. Keep it going and fix that baby up!
 
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