2013 Pro R 800 low rpm, low top speed

[portpolaris]

I was hoping someone could point me in the right direction as to what is causing poor performance from my rush 800. It currently has 2000miles on it and I have been noticing that it won’t hold the rpms like it used to and top speed is weak.

If you hammer on it from a rolling start the rpms shoot up to 8150 - 8200, but as your speed goes up, the rpms drop to 7950. Top speed from the sled is in the high 90's. This is using 91 non eth fuel, and on the non eth setting. If I switch to the eth setting it gets worse - 7500rpm. Power valves and clutches have been recently cleaned by dealer, and I’m told that my TPS setting has been re-calibrated. I had 125/126 psi compression at the start of the season, but will recheck soon.

I'm kind of lost on what to check next, would a poor performing fuel filter be the cause? If the TPS setting had to be adjusted once, could it be acting up again? Broken clutch spring?

Kind of disappointing when my buddies 600 rush get 103mph....

 

[TRS]

I was hoping someone could point me in the right direction as to what is causing poor performance from my rush 800. It currently has 2000miles on it and I have been noticing that it won’t hold the rpms like it used to and top speed is weak.

If you hammer on it from a rolling start the rpms shoot up to 8150 - 8200, but as your speed goes up, the rpms drop to 7950. Top speed from the sled is in the high 90's. This is using 91 non eth fuel, and on the non eth setting. If I switch to the eth setting it gets worse - 7500rpm. Power valves and clutches have been recently cleaned by dealer, and I’m told that my TPS setting has been re-calibrated. I had 125/126 psi compression at the start of the season, but will recheck soon.

I'm kind of lost on what to check next, would a poor performing fuel filter be the cause? If the TPS setting had to be adjusted once, could it be acting up again? Broken clutch spring?

Kind of disappointing when my buddies 600 rush get 103mph....

Find a dealer that can perform a proper leak down test.

 

[portpolaris]

Can a motor fail a leak down test but still give a good compression test?

 

[geo]

Absolutely. But other things wear out too.

At 2000 miles something a simple as a belt or clutch spring replacements can cure rpm problems.
Did it ever pull over 100mph?

 

[akgiauque]

My 12 Pro had the same issue. Third time the dealer warrantied the clutch, problem solved. Said it had an unusual wear from binding that the tech cleaning it the first time missed.

 

[portpolaris]

Was it the primary or secondary clutch? My belt has been changed recently. The sled has hit 100 mph, but only when held to the bar for a really really long time on perfect conditions tucked in. Bottom end it still rocks.

 

[sledneck_03]

My 2008 700 was doing the same... Exhaust doughnuts lead was completely gone.

Friend 2011 is idling 1600 and only reving 7900 with 1600 miles.

Told him to check tps, think hes going to do a fix kit this summer too.

 

[portpolaris]

TPS sensor has been gone over and it's 100%. Took clutches apart, and every thing looked good. Re-did compression test 125/126. Only thing left I can think of is fuel filter, and it's been ordered. Just waiting on shipping.

Anyone else have any ideas?

Having a bad Exhaust doughnut can effect top end speed and rpm?

 

[spark2]

I would put a new primary clutch spring in and check belt or new one.

 

[roni87]

This sounds like my sled exactly.
Hits 8200 on trail then slowly down to 78-7900...
Cleaned valves, tried different primary springs, tried older secondary clutch, new plugs.

2012 assault rmk, 1500mi. Drop in kit top speed 91. elevation 1200ft. Non ethanol setting, ethanol plug makes it worse. 10-68 weights.

Since the ethanol plug makes it more doggy, I'm wondering if it's running too rich to start with? Had one time at night after a 10 second pull on the trail it was flaming out the exhaust for about another 10 seconds???

 

[portpolaris]

Have you changed your fuel filter? I have one ordered, but they are out of stock. Let me know if you find a solution.

Iv checked both primary and secondary over, no issues there.

 

[twwillard]

Have you changed your fuel filter? I have one ordered, but they are out of stock. Let me know if you find a solution.

Iv checked both primary and secondary over, no issues there.

u need new pistons have the dealer pull the head off u will see real bad piston wear we changed about 8 sleds piston wore out polaris problem

 

[portpolaris]

How do I convince my dealer to pull the head when they do a compression test and it meets specs?

 

[roni87]

I believe a lot of my problem was a sparkplug cap. I found the mag side plug real wet compared to the pto, so I checked inside the cap and the mag cap was real dirty/dusty inside. Probably arcing pretty bad. It ran much better after switching this wknd but still rpm sliding down to 7900 sometimes.

Fuel filter is on my todo list.

 

[portpolaris]

Talked to dealer, ECM was shorting out and back feeding TPS. Hopefully this is the cure....

 

[geo]

More info??

Common? Internal? Lot of little wires going in there lol.

 

[roni87]

Pic

Picture would be good of the area that was affected. Or like geo said, what wire had the short?

I just tried a bunch of different weights, primary springs, different gearing on mine tonite...not really any better.

 

[portpolaris]

ECU and fuel filter replaced. Problem not solved. Frustrated and dissapointed.

If you cant beat them, join them. Etec here I come.

 

[ak]

Install new secondary spring, and primary spring, new belt and set the deflection proper.

What temps are you running on your gauge.

Clean power valves?

 

[portpolaris]

tryed new springs. cleaned valves twice. new belt, proper deflecton. 93mph top speed.