RM125 concern

My dirt bike seems to have a problem going through the RPMs. So here is what will happen. I'm going good and it hits the powerband for a little then it just starts to not have as much power as I think it should. It only happens at high RPMs and it does it in all gears.anyone have any ideas.

It Mau have something to do with your power valve. Is it sputtery or runs like crap?

No it's not the valve. I had just done that. I know the valve is ok so I have no clue what else could do this.

Do you know what your main jet size is? Sounds to me like your running way too rich (too much fuel to air) Try leaning it out and maybe raising the needle clip position

175 main 55 pilot for a 125 2 stroke

If I remember right, on my old 125 (that was jetted perfectly) I went back and forth from a 180 main jet and a 178 along with my needle in the 3rd clip from the bottom.

So could it be to much air in the carb? Cause I just checked and the screw was loose.

Which "screw" are you talking about?

On the 1998 rm125 carb the choke and idle screw are in one screw and it was that screw.

Ok. Well I would buy a 180 and 178 main jet, try them out and see if it helps. Your carb could be dirty too.

Ok so I should do a carb clean and new jets. Is there anything I can put in the gas that will clean the carb on a 2 stroke?

No there is not. Try new jets first, and if that doesn't fix it then clean the carb. It's a bitch to get the carb in and out

Ok. Thank you

Ok so a little more research. The FMF website said 168 main 50 pilot. And. could it be caused by the clutch?

i'm from MA as well and my 125 didn't run good with the 175 main jet. i put in a 170 and moved the needle to the 3rd clip, and its a night and day difference.

i'm from MA as well and my 125 didn't run good with the 175 main jet. i put in a 170 and moved the needle to the 3rd clip, and its a night and day difference.

Do exactly what he said

Ok thank you for the help. Really appreciate it.

No problem dude! Tell me how it turns out!

Will do

are you sure your powervalve govenor is working right? i had about the same problem where it woul say load up and it was mypowervalvegear being stuck.

or it's your coil failing under load like mine did.

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