Anyone familiar with a revving sound, that isn’t the engine??

[HUS457]

Hey all, bit of an odd question. Seems like after about 150klm into a ride, I can hear a faint sound from the cowl that almost sounds like a sled in the distance revving?

Belt on or off doesn’t make a difference. Can’t tell if it i does it when moving, it’d be too quiet. No lights or codes.

Any ideas?

 

[KnappAttack]

Turbo

 

[HUS457]

Really? What causes it? I was riding with another Sidewinder, he said he hadn’t heard it before either. The only relatable difference I could see between the 2 was the ROV. (His was a 17). I heard the turbo gurgle when I shut the sled off, It’s not that. Almost sounds like a 2 stroke ditch banging in the distance.

 

[Norse]

I've heard this on my car. Turned out I forgot to put the insulation back in place after checking the hydraulic pump (active suspension). Do you have power steering? Could also be fuel pump?

 

[HUS457]

I've heard this on my car. Turned out I forgot to put the insulation back in place after checking the hydraulic pump (active suspension). Do you have power steering? Could also be fuel pump?

Thanks for the reply Norse. Yes it has power steering, which is another thing different than the 17 I was driving with. When I loosened the gas cap it didn’t make a difference. Putting my ear up to the fill hole didn’t sound like it was fuel pump.

Has anyone else with eps sleds heard this noise?

As KnappAttack mentioned, possibly turbo as well. KnappAttack, do you mean like a bearing failing? Or just regular turbo stuff?

Heading out today for what’s probably last ride of the season. I’ll have to take a closer look at it over the off season.

 

[74Nitro]

Really? What causes it? I was riding with another Sidewinder, he said he hadn’t heard it before either. The only relatable difference I could see between the 2 was the ROV. (His was a 17). I heard the turbo gurgle when I shut the sled off, It’s not that. Almost sounds like a 2 stroke ditch banging in the distance.

The 2021's and up had different plumbing that make a goofy sound.

 

[Richard Hodgins]

Its the ROV, my 22 did the same thing, a weird huffing sound.

 

[KnappAttack]

KnappAttack, do you mean like a bearing failing? Or just regular turbo stuff?

Either I guess.

Could it be the clutch rattle at 4-5000 RPM perhaps? Or like others have said, the ROV also makes a pulsing sound at idle, I don't know if it does this while riding however. I always bypass them so don't know that answer.

 

[HUS457]

No, not the clutch. I know that sound. Throttle doesn’t seem to affect it either.

ROV is becoming the biggest suspect.

Sounds like nothing to be concerned about though, excluding ROV lead oil leak.

Thanks for the responses fellas!

 

[Norse]

My '23 ROV only made a popping/puffing sound at idle, just releasing pressure I guess. I could clearly hear it if I put my ear to the intake.

But revving sound? Is it consistent, what rpm, is it at idle, does it sound like a water pump speeding up?

The pump in my car was actually the vacuum pump now that I remember correctly. It sounded like a gas powered RC car revving at a distance.

 

[Teamblue4]

Gas tank vent ?

 

[HUS457]

My '23 ROV only made a popping/puffing sound at idle, just releasing pressure I guess. I could clearly hear it if I put my ear to the intake.

But revving sound? Is it consistent, what rpm, is it at idle, does it sound like a water pump speeding up?

The pump in my car was actually the vacuum pump now that I remember correctly. It sounded like a gas powered RC car revving at a distance.

Yes it’s a revving sound. The tach on the sled doesn’t change, and a little throttle doesn’t change the revving sound. So it’s not engine. It’s the same tempo. Best way to describe it is like there’s a 2stroke off in the distance revving up & down. Approx every second. Revs up for a second, the down for a second. Consistent. My sled tach doesn’t change other then the usual 50rpm that it fluctuates, belt on or off doesn’t effect it, and if I give the sled a little throttle it didn’t effect it.

I just got the sled at the end of February so I’m just getting use to it now. I paid more attention to it yesterday and can add that it does it all the time. Not just after 150k likle I originally posted. It was doing it when I took it off the trailer. Sled performance is not affected either. It still hauls.

 

[HUS457]

Gas tank vent ?

I thought that too. But I took the cap off while it was running & didn’t affect it.

 

[NYTurbo]

Disconnect the ROV hose from the top of oil tank and see if it goes away