RM125 Trouble Starting

Hi all, I am new here and am having a bit of a problem. 


I have a 1994 RM125 that I have owned for about a month and a half. When I purchased the bike it would always start on the first or second kick but wouldn't idle. I have replaced the spark plug and had my roommate who is a marine/ small engine mechanic tune the carb so it would idle. Now it is a pain to kick over, but once it is running it runs like a top. I have about 145 lbs of compression and the carb is as clean as could be. 


What should I look at or do to make my bike easy to start again? 



I get the feeling your "marine/ small engine mechanic" had no idea what he was doing ,

How would you go about fixing it then? 

Get it running, then properly adjust the air screw per the pinned post at the top of the forum.

You have to start with the lowest possible idle (slide positon) before adjusting the air screw.

You also have to learn the best starting procedure for your bike.

If you have not changed the rings and piston since you bought it , do it.  

Since I don't want to start another thread I will bump this one. 


In the last 2 days I have worked on the bike and cleaned the carb, which was actually really clean, and made sure nothing in there was clogged. I got the bike all put back together now and it is getting gas and spark but not firing. 


Does anybody have some suggestions on where to set the carb screws to try and get it to start so I can go from there. 


I'm open to suggestions as well. Thanks. 

Did you put in a brand new pilot jet?


You pretty much have to.

Reeds good?

Do a leak down test?

Compression test?

I didn't put any new parts in the bike. The reeds look good, no rips or tears, and a compression test tells me I am at 175 psi. Also when I poured a little bit of gas into the top of the cylinder the bike would fire.

Edited by hedsRM125

Sorry, Double Post. 

Edited by hedsRM125

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