The stator area was pretty clean, I cleaned the drum and the pickup real good with no improvement. I checked the exhaust and the reed cage and all is clean. I'm at a loss, What should the compression be? Maybe I need a rebuild. That would seem like the problem since the engine don't have any power.

 

Kinda hard to get a compression hose between the frame tubes,but I always used a easy way of telling,just place your thumb over the plug hole and see if it can pop you thumb off when cranking Silly I know,but you can tell real quick! If you barely feel pressure,then you probably need a new top end. Off top of my head since I can't remember what the manual suggests, I would think at least between 95 and 120? If you do decide you can find new complete cylinders and piston kits sometimes cheaper than having a shop bore it out,plus parts. PLUS do you have a good exhaust flow? Have had to remove exhausts before to chip out carbon deposits around the exhaust port that would block flow,plus have even tried to clean out mufflers with solvent and blow em out with an air gun and even have resorted to,with owners permission to use a long punch and drive through the tail pipe into the muffler to open it up so they would run better!Some would just get clogged with oily carbon build up! OPT

 

you are asking great questions that i don't have the answers for.it is not an accident that i guessed that it was a 2001 w/electric choke.i always swore that when i saw someone with same issues that i would try to prevent them from going through what i did.please,for $60-70,get the conversion kit.

 

I understand where you are coming from jeepcrazy. I'm going to check compression today, if it's low I'll do the top end if it's better than 90psi then I will get the choke kit. BTW where is the best place to get a top end kit with jug? and where to get the choke kit? Thanks.

 

Granted the choke kits will help,but if it won't start with a new carb by blocking off the air box inlet tube then I think he might have other problems! The choke kits were not cure all's for the little 90 engines as I still had to block off air tubes on these even with the kits if they sat for awhile or temperature was very cold! That's why a lot of people when I showed them how to start them (from the tech bulletin we received from Polaris) didn't order the kits! When the 2 strokes were discontinued and the 50 and 90 four strokes came out,starting problems disappeared along with stator problems,clogged exhausts,low compression because of the 2 stroke faster top end wear, etc. OPT

 

OPT is spot on as usual with his latest post.when it is cold outside,i still use the "air restrict w/hand"method.when it is warm,i just use manual choke only.e bay item#230686655742.polaris #2874547.please post back when you get it figured out.someone on another forum was as adamant as i am when i was having my issues.wish i would have listened to him much earlier($$$$$$)would have cost much less even though i was at the point of just "throwing parts"at it.good luck!

 

Well, As I stated ,with the new carb it starts and idles just fine without any assistance and will idle great all day. Problem is the engine don't have any power with the tires on the ground. but when on stands it will run like a champ all the way to full throttle with everything working fine (clutches and everything). But I can hold the tire with one hand and try to throttle up the engine just bogs and I can keep the tire from turning. I just did a compression test with an automotive tester and it barely registers (about 10psi) and with my thumb on the hole I can barely feel it.

 

Think you found your problem! You might check on the complete aftermarket cylinder/piston kits or if you have a good shop,usually first oversize will clean em up on the piston,but best to have it measured. Complete brand new cylinder and piston kits with all gaskets are 99 bucks on E-bay.. OPT

 

This may sound funny but how can I tell for sure what model of polaris I have? All it says is Polaris on it. I took everything apart and cleaned it. I just put everything back together and it does run better but still WAY underpowered. It'll go about 20mph or so with me (200lbs) on it.. The vin is RFLNA0921XA000390

 

Engines were the same on the Sportsman 90 and Predator from 2001 until they were replaced by the four stroke 90 and 50. The 2001 models were originally orange,at least all the ones we sold ! Looks like you have an aftermarket Maier plastic??, the Polaris sticker looks aftermarket or it's my old eyes too??Yellow was offered,but don't remember any with ridges on the fenders,plus the dual lights?? They had dual lights on the later Predators,but the body style was different! It's been only 10 years or so,can't remember all the body styles! Plus should have a little metal front bumper brace on the atv with the serial # etched on it,if I remember correctly?. Plus either Eton Or Aeon built basically the same atv and supplied the atvs for Polaris. OPT