Need help

[tanner]

Well i dont to think. I have a 02 RMK 800, it has a port&polish, v-force reeds, twin split second pipes.(no vari-flow). Anyways the engine is suppose to make max hp at about 8400rpm (160hp). When the engine is cold it will pull 8400 all the way to the top of a long climb(the first time), the second climb it will pull 84 untill about 2/3 the way up then it will instantly drop to 7400 plus or minus. Short climbs it works all the time. I have been told that the engine timing retards if the water temp gets over 140F so i removed the water temp sensor there was no change. We rode in valemount so about 6 to 7500ft. I jetted lean to 350 jet running 1380 exhaust temp and fat 400 jet 1250 exhaust temp still no change. The clutch weights are 10-62 i could try 10-60 but i don't think that is the problem. I will take it in for a dyno test soon but if anyone has any idea i would appreciate the help!!. PS i run straight AV gas.

 

[Summitric]

Sounds Like A Clutch Problem, OR CLUTCHING.... Did This Suddenly Start Happening, Or Been Dooin' It A While???

 

[cey800]

Make sure you exhaust openings in the belly pan are well sealed, along with the exhaust joints. How long is your exhaust deflector on the bottom of the belly pan?
Cheers

 

[tanner]

As long as i have had the machine. If it is the clutch i don't understand why the drop happens instantly. I dont know a lot about the clutching system but i thought the drop would be gradual like loosing hp this happens in a half second. the prymary spring is new and i checked the secondary every thing look good. Thanks for the fast responce.

 

[tanner]

The exhaust is out the belly pan about 1 inch. I also tried it with the hood off just in case of exhaust leaks. one good thing about a lite weight hood. thanks for the responce.

 

[BIGFOOT]

Does it sound like the engine is retarding on the pulls when the rpm drops... That should give a guy some direction to checking. A 800 should pull 16-62 wts no problem. How are the exhaust valves & what color springs ?

 

[cey800]

What is your clutching set-up? I run one 800 VE with stock clutching and 60g weights and it pulls hard all day.

 

[Deano670]

How long have you OWNED this sled?? I do know that split second pipes work much better cold, they make instant HP but are not worth a hill of beans for repeated long climbs. My last split second engine made 162hp I ran 66 gram weights in it however it did have a roller secondary which changes things a bit.It could be that once your engine is hot and the power is down that the LIGHT clutching you are running is shifting to soon and the engine cant recoupe, it would appear that way seeing as to how on short pulls or one good long pull it works just fine. Try throwing more weight in the primary!!!

My two cents

 

[tanner]

The exhaust valves are in good condition so they say at the shop. They have been cleaned and checked at the beginning of the season.(also a top to bottom overhaul) I don't know if the engine is retarding it happens to fast, the engine sounds normal just no power at the low rpm. The engine will hold the 7400rpm untill i turn out 5-10 seconds. The prymary spring is a black/green and the secondary is black if i remember right.THANKS

 

[tanner]

DEANO670: I have had the sled since last march. 2 trips to the mountains last year and it had the same problem. I sure wounder about the pipes that is why i tried with the hood off and jetted down to drop exhaust temp. I will try the heaver weights though. If i take to the dyno it would be nice to try it there. What kind of a roller secondary did u run? THANKS for the info!!

 

[SLEDBUNNYRACING]

I'd stay on the clutching. I run a 2001 with sumular mods and different pipes. I had Rory at Motorsports Addiction clean up my clutches last spring and the results were great.
My button ramps on the secondary were quite worn and when replaced it make a huge difference....just my 2 cents worth.

 

[Deano670]

I ran a polaris secondary with a highmark roller kit, nearest i know they dont make those kits anymore, however the Team and Cat roller secondarys do work VERY WELL with what your trying to do. As far as your clutching goes are you using a Yellow sec spring in like about the 2nd or 3rd hole. And my exp with split second pipes and clutching is you need to load the engine up hard and fast and they work awesome

 

[Deano670]

In addition to what SBR just posted if those PUCKS in the sec are worn really bad like to the point at which your on a metal to metal surface your sec WILL NOT shift properly especially when your on and off the throttle, if the sec gets stuck open when you let off then you get back into the throttle its like starting off in 2nd gear. Which may explain why it WONT pull over 7400rpm

 

[tanner]

What is your clutching set-up? I run one 800 VE with stock clutching and 60g weights and it pulls hard all day.

I'm not sure even what the stock setup should be. Black/green prymary and black secondary in a team clutch. Pulling hard all day is better than unreliable horse power. It does out climb a stock 800 dragon and a piped,reeds y-pipe M-8 when it runs right he will pick up a boondocker for it now. 2008 m8 is a great machine thought I like it. PULLS HARD!!!

 

[SLEDBUNNYRACING]

Clutching is so important, especially when you add more HP.

Good Luck.

 

[tanner]

I ran a polaris secondary with a highmark roller kit, nearest i know they dont make those kits anymore, however the Team and Cat roller secondarys do work VERY WELL with what your trying to do. As far as your clutching goes are you using a Yellow sec spring in like about the 2nd or 3rd hole. And my exp with split second pipes and clutching is you need to load the engine up hard and fast and they work awesome

I cant get the dam secondary apart now but there is no holes in the secondary for the spring, the spring is flat on both sides. It suck not knowing about this stuff becauce it hard to explan. The helix in the secondary has only 2 slots and there is 2 about 3/4 rollers. I dont know if this is stock?. mayby this is what a roller kit is? The part# is
58-42-46-ER also rapid reaction 541 08/07/03.00.53 if that makes any sence? Thanks for everyones help

 

[SLEDBUNNYRACING]

Maybe this link will help.
Polaris Info LINK

 

[Deano670]

Do you have any pics???

 

[tanner]

Clutching is so important, especially when you add more HP.

Good Luck.

Sounds like it could be a clutching problem by what everyone is saying. I will take them in and have them checked. I will be playing with the weights next time i'm out.Thanks

 

[tanner]

Do you have any pics???

I will get some pics up as soon as i get it apart.