Whining noise when engine breaking (video)

[VentureRS]

Hello,
I recently purchased an -05 Venture RS and it's my first 4-stroke - hence im a bit unfamiliar with the sounds it makes in comparision to my old 2-stroke.
Apart from the rattling variator noise that seems to be normal - it makes a quite loud whining noise whenever im in movement and let go of the throttle.
Going downhill the noise is constant and goes away whenever I give a little throttle.

Having read about complete engine break-down due to faulty chaincases - I would be very grateful if anyone could make out if this is likely coming from anything related to that or not.

/BR

 

[Viper_Dave]

Check your chain case tension. Finger tight and back out 1/4 turn. I've had every 1 of my sleds make this noise at 1 time or another. Usually it cures it. If this doesn't do the trick, you'll likely need to pull the chain case cover and inspect. Could be chain or gears. Could be bearing. How many miles/kilometers on it? I've replaced all bearings at around 10,00 miles as a safety precaution. I'll be traveling throughout the day and will check this thread this afternoon.

 

[sideshowBob]

Check your chain case tension. Finger tight and back out 1/4 turn. I've had every 1 of my sleds make this noise at 1 time or another. Usually it cures it. If this doesn't do the trick, you'll likely need to pull the chain case cover and inspect. Could be chain or gears. Could be bearing. How many miles/kilometers on it? I've replaced all bearings at around 10,00 miles as a safety precaution.

X2...

 

[VentureRS]

Hi again,

Thanks for the feedback - the sled has 11000km on it - so could definetly be some type of wear. I got it through a dealer though so they did inspection/service on it - but guess they just ran the sled stationary.
Unfortunately the sled is at my cabin 5 hrs away, but will check the chain case tension next time im there!

 

[maim]

i agree on chain case tension too tight. i also did the bearings in the chain case at 16000 km as i had a speedo bearing failure and decided to do them while i had it apart.

 

[thor452]

my apex and my buddies all make that noise when you are on a hard de-cell I thought it was normal 30,000 miles between us and all 3 do it when engine breaking.

 

[72Gran]

It normal, my xtx does it all the time sounds identical. I find that when the belts gets worn a bit the noise is reduced because back shift is not as precise, it’s one way I know it’s time to adjust/change the belt.

 

[03RX1-ER-LE]

All three of my old RX1s did it, both my Apexs, and my buddies Attack also does it, normal!
Yes all the chain cases were set to spec, and each season when changing chain case oil there was no debris in old oil drained.