The noise is "normal". I wouldn't worry about anything failing. I've ridden other brands....just about all machines can make that clatter/rattle sound. Go down a rough, rocky hill and jab the foot brake or rear hand brake repeatedly and things rattle. Due to manufacturing tolerance and clearance needed to assemble components, there is backlash inside the CV joints, the CV joint shaft spline fit into the rear drive, the rear drive gears, the driveshaft splines that connect to rear drive and transmission, the u-joints, 3 sets of gears in the transmission, the jaw clutch used to shift gears, and in the CVT. All of this play creates noise when torque fluctuate from drive to coast. Tighter tolerances on everything would help, but then these things would cost even more

 

Dont worry about the noise ive had mine for a year and a half and 3000 miles its the ebs engine brake it makes noise but its not a 3000 mile throw away 4 wheeler like a yamaha it will go 12,000 miles like my 2002 700

 

Thanks for the info. I will take a look at my transmission drain plug and see if there marks from the chain. I was also thinking about putting Lucus transmission oil in the transmission to see if that quiets it down. Not worried about the warranty since polaris only offered 6 months and it's expired now. As compared to an 09 Polaris Sportsman 850 it does not have the clank sound in the tranny. I test drove one in Utah and was quiet suprised how smooth it was. I drove it faily hard over bumps in high gear and it was quiet. The exhaust sounded the same as my 08 800 SP, and I noted that it only have one exaust muffler instead of two. The seat was narrowed down and of course the engine was turned sideways and the suspension was different. I now think I would like to buy one. Also looking at purchasing a RZR so I can take a passenger.
If anyone has an remedies for the noise problem please let me know. I will follow up with a post after I try Lucus oil. thanks again.

 

pretty much the d. plug is the only way to quiet part of it as for the rest of the noise, its how the bike was built w/ too muck loose tolences. most of us have learned to live w/ the noise and some guys have alot of trouble free miles.

 

I wouldn't mess with the oil. Depending on which type of Lucas product you are talking about, some of their claims are for noise related to clutch disks (plates with friction material) like those in an automatic transmission. The Polaris transmission doesn't not have these. Changing oil brands will not physically change the amount of play between parts. A higher viscosity oil (thicker) could potentially help act like a "cushion" as part come together, but it could potentially hurt too. The transmission uses splash lubrication...the gears and chains fling the oil around to get it to splash/spray to all the necessary parts. If you put a thicker oil in it, it may have a negative affect. Some parts may not get proper lubrication.
Not sure what secondary clutch you have. I've heard the TEAM secondary has less backlash in it and can help with some of the clatter one hears when you're on and off the throttle.

 

Thanks ATVCONNECTION, STENDORI and all that responded. I have been doing some extensive research on why my 2008 Polaris Sportsman has a rattle/clanking sound when I drive down hill in two wheel drive. I read on this forum that the transmission bolt was too long and was being hit by chain inside the transmission. SURE ENOUGH I PULLED OUT MY TRANSMISSION DRAIN PLUG AND IT WAS BEING GRINDED AWAY from the inside. I used my dremel tool and took about 1/8 inch off and rode it today about 30 miles. I barely heard the noise at all. The clutch worked perfectly and now it is a whole new quad.
I also put in new "Polaris transmission fluid" in my transmission. The clutch/transmission worked perfectly. The noise I was hearing was definately the transmission chain rubbing against the transmission drain plug. It's been a great day...thanks again guys...

 

I have owned polaris since 2004 all have the clunk keep riding.....