My RM250 Making a Supercharger sound!

[joeym4130]

Goodday everyone,
I was riding today and after the session, I was sitting in neutral and at low RPMs while sitting there i hear this weird sound. Its a weird sound like a supercharger would sound on a car at low RPMs. Or like someone is blowing a gym teachers whistle at a low volume. lol. I looked it over quick when I was out and nothing was loose or rubbing against anything, but I couldnt pinpoint the origin of the sound either. It just sounds like its coming from the area of the motor. Might need a stethescope.

If I rev it up the sound either goes away, or I can't hear it. Rode it WOT on teh way home and it didnt have any problem.

Didnt know if I shold just start ripping the bike apart or if something sounds familiar to someone here.

 

[mg89]

I have that sound on my rm125 too, like a whistling sound.

 

[joeym4130]

I have that sound on my rm125 too, like a whistling sound.

Has yours always done it? I never had this before, then after todays session, was when I first heard it. I just didnt know what to make of it, since I can't seem to pinpoint the source.

 

[kx125412]

you're probably just hearing the piston moving in the cylinder.

 

[phranticness]

vaccum leak? loose carb clamp, can you change the tone by wiggling the carb?

does the noise only go away with RPM?

can you change the tone with the clutch?

 

[joeym4130]

I'm going to give the bike a quick check tomorrow. I'll check the things mentioned with an extra careful eye, and report back. Just wasnt sure if the whistiling noise was a tell-tale sign of anything severe.

Tone doesnt change when engaging clutch or antyhing like that. And once I'm moving the noise is either gone or I just can't hear it over the pipe.

 

[BSWIFT]

Check the water pump impeller. This will cause a sound like you discribe.

 

[joeym4130]

Check the water pump impeller. This will cause a sound like you discribe.

Hrmm. Took out the stethescope and it seems like its originating at the water pump. Taking it apart later this week .....