2006 90cc polaris sportsman 2 stroke roungh engaging
 

Today I picked up a used 06 polaris 90cc sportsman for my kids. It looks decent, but needs a good once over and some things could use work.
The thing that stands out the most after watching more videos of them is mine engages kinda rough and abruptly. It doesnt matter if I put it in forward or reverse, I have to give it close to 3/4 Throttle before it will click and engage taking off very abruptly. In the videos mist of them could take off much slower. I have a couple guesses on what to check but thought I could have a better idea if I asked on here first.
Does anybody have any ideas? Belt? Weights? Clutch? Or what to do with them to fix it and be able to take off slowly?
I was thinking of putting on a smaller front gear and larger back gear too to slow it down and give more torque for hills. Anybody done this?

Thanks,
Ryan

Welcome to the forums.
First thing is to maint the clutchs to see if anything is wrong/wore in there.

As LT80 mentioned check the belt for wear and excessive slack. Also jerking engagement if the belt is not the problem can be from worn rollers in the drive clutch and the shoe type clutch in the driven clutch.Items 6 and 28.Dirt Cheap Yamaha, Polaris, Suzuki & Kawasaki OEM Parts & Accessories – Cycle Parts Warehouse

Awesome! Thanks for the replies. Do you know if there's a how to video or pictures for disassembly? I just want to cover my butt if I take bolts out I shouldn't have and it falls apart before I get the cover off.

I looked but couldn't find anything...get a manual and take photos with your phone for install reference...parts fiche can also be helpful...sometimes...

Here's a cheap one for 5 bucks.2006 Polaris Sportsman 90 Service Manual PDF Download

I found a video of a guy taking apart cvt on a moped that was pretty close in looks and really helped.
Unfortunately the cover gasket got wrecked and came off in pieces after I had to pound on the cover like crazy it was stuck on so tight. I'm not sure what the wire thing is for but don't look good. Hope it's not a pain to replace. The belt is pretty glazed and one of the rollers has a tiny flat spot. I'm not sure how critical that is or if I should just polish them up or turn it back round on the lathe at work. There sure was a lot of dirt in there. The guy kept telling me everything was mint like new. Low hours and never touched a thing since he bought new in 06. The way the rest of the machine is grime wise it looks pretty neglected. I think I overpaid at $1175 all he would budge from $1250 because he said it was such good shape and good deal. Too late now hopefully I don't find any other surprises.
Where's a good place to get a cheap belt?
Thanks
Ryan

Wires are to the gear position sensor. Item#28 on the parts break down. Dirt Cheap Yamaha, Polaris, Suzuki & Kawasaki OEM Parts & Accessories – Cycle Parts Warehouse There's a complete rebuild kit on ebay that's reasonable,BUT don't know how good it is compared to the higher $ oem parts.Transmission Rebuild Kit Polaris Sportsman Predator Scrambler 90 ATV Clutch Part | eBay If you wish to stay with oem parts either Cycle Parts Warehouse,Partzilla are probably the cheapest online parts houses. If just want to try a belt.http://www.ebay.com/itm/KEVLAR-DRIVE...ZTvja-&vxp=mtr

Awesome! Ur the man. Thanks, that saved me some time. Hopefully get some stuff ordered today so it's here in time to put back together and running by my son's 8th birthday party next Saturday.

Those damn fender bolts are a pita. Had to drill and cut off most of them. Stupid Phillips bolts with nuts rusted to back. I'm gonna try find some plastic ones to replace them with to make removing easier next time.

Finally got all the plastic off, power washed it good. What a mess. Definitely the dirtiest quad I've ever bought and this is my 3rd one. I drained the gearbox oil after washing it and it was chocolate milk. I highly doubt it was from my washing because I taped off with plastic bags everything that could get water into it. The milk barely looked like oil. It was even lighter and whiter than chocolate milk. Theres no coolant in these or id think it was a bad headgasket. A couple oil changes will be in its future.
Any oil to recommend?