motor knok

[kwik man]

My motor has around 10 hrs on it and know I can hear
a knok comeing from the top end on the timeing chain side when
the motor is under a load. I replaced the timeing chain adjuster
didn't help can some one tell me what might be going on with
this motor

[WesDS450X]

my motor is very knocky also, but iv been told thats just normal for rotax

[represent618]

so they sound like CANNONDALE?

my cannondale was loud sounded like it was coming apart when you run it, but it was one awsome piece of equipment.

[Wes450x]

im not 100% sure i do kno my motor knock is louder then my frineds exhuasts at idle lol

[fastford]

Just a thought but are you running 91+ octane? The motor is a 11.8:1 compression and a low number will produce a knock. I know mine is noisy but no where near hearing over another quad.

[WesDS450X]

Yep runnin 93 right meow its like barly louder then there exhuasts at idle, seen another ds450 at the dunes the other day and hes motor was the same way, havent had any problems with the motor or power loss and i was told its perectly normal for the rotax

[kwik man]

I went to the shop they told me to check out the timeing chain and timeing chain guides. Pulled the valve cover off and the left side motor cover off checked both the chain and guides didn't find a problem with them went back to shop they wanted me to check the decompresson valve on the exhaust cam. The dccompresson valve moved freely when I pushed it in and let it go it returned back to it's starting point. The decop valve was ok so I installed a new timeing chain tinchiner put bike back together started up the bike and it didn't knok. I don't know if this fixed the problem or not time will tell.

[WesDS450X]

so i took my bike to teh can am shop today, about the knock, they told me its perectly normal, dont worry about it

[mike_1985]

So whats the deal with the petrol octane ? I run it on supreme 99 ron no problems just a bit faster