My new XP 550 shakes,rattles and viberates terrible when it is first started..It now has 510 miles and nothing has changed.It also makes a strange noise when it is shutting down (turned off) Sounds like it is coming from the clutch...Other than that is is one awesome machine..Just moved up from 2007 Sportsman 500 EFI Deluxe.

 

My 550 has a slight vibration but to me seems appropriate for a single cylinder in the 550cc range. I wonder if your plug didn't foul at some point and may be less than perfect. It's an easy check.

 

Mine run just as smooth as my 2 500 rubicons. Have ever had a single before? If your used to a twin the single will seem like it has more vibration. Since I can't see or hear it run first hand, the only advice is go to a different dealer and start a new Xp up and compare. Also, mention your concern to your dealer so if something is wrong they will fix it under warranty even after the warranty is up.

 

Could the noise you hear be the idle speed control stepper motor resetting? I haven't heard of anyone with a 550 reporting a noise after shut down. And I think that the ISC is the same on the 500. I know the 850 uses a slightly different system call an Idle Air Control Valve and it is normal for the IAC to make a noise when it resets after shut down.. Kind of sounds like a small motor and gears turning(which is basically what it is lol)

 

I started a 550 at my dealer... had more vibration than my 500... even when fairly warm.

It would probably annoy me.

 

I have owned 4 500 Sportsman's and they were very smooth compared to the 550 at idle..The spark plug is fine..We were just playing with the 550 and everyone was amazed at the rattle and noise at start up...

 

The 550 rattles and viberates at idle worse than any machine I have ever been on. That is just how it is. As soon as You give it gas it smooths right out. I love my machine but the idle takes getting used to. As for the noise after shut off highoctane has the correct answer.

 

And there's no excuse for it. The engineers at Polaris must have been on coffee brake during that test. LOL They could have done better... and probably will.

Anyhow, I've talked to a couple of guys locally that have walked away from a 550 for just that reason. One of them was right at the dealership. I know I would pass on one for just that reason. I'm sure it's a great quad otherwise, but that kind of stuff drives me crazy.

 

I don't know .... different strokes for different folks. I have an 850 that is smooth as can be and the 550 with a slight vibration at idle which IMO makes no difference. I bought the quads to drive and slight vibration at start up has nothing to do with how that quad goes down the trail. IMO this vibration thing is splitting hairs. A much better discussion would be how the machine climbs or how the suspension works or how good the four wheel drive works or how comfortable and balanced it is, ect. Sorry but IMO vibration at startup is a non issue other than the original comment to determine if there was a problem with Delux500's quad or vibration at startup was normal.

 

also the 550 has a higher idle that could be the reason. mine does the same thing.