Rpm fade....clutching or ECU?

[tincuprider]

I've seen a number of threads on rpm fade on the Axys and the bug finally got me at about 600 miles. I thought I was due to put the new belt on anyway so I swapped it out and sadly there was no improvement whatsoever. The rest of the day I watched my rpms waffle from a best of around 8200 to a worst climbing one long grade of around 7000. Most of the day it was 400 to 500 less than its run all year.
So my question. I've noticed over the years on my Pros there have been times in high altitude combined with warmer temps and high humidity the sleds just fade out and lose several hundred rpms. Those conditions describe fairly well the conditions I was riding on my Axys on Saturday. Is it possible the ECU just isn't leaning the sled enough and its creating a too rich situation which is making her sick enough to multiply the altitude sickness already present resulting in the fade?? I thought some of you guys that run controllers might have an opinion on this situation. Any thoughts would be great....thanks.

 

[snobyrd]

It does say in the owners manual to use 2 grms lighter in warmer temps,

 

[NoSoup4U]

I've wondered the same thing. It was a warm day 2 weeks ago and I was down 150-200 rpm from what I normally see. Last weekend was colder and the RPM were back up (borderline too high). I did adjust my belt deflection prior to last weeks ride, so I'm not sure if it was temperature or the belt adjustment that made the difference. Maybe a combination of both.

 

[Jaynelson]

Could be worn rollers or a broken spring

 

[steepndeep800]

History from the short tracks last year is all the above are very possible.
Some are more sensitive to the temps than others with the TPS setting being all over the board.
Some where out rollers, not to common but did happen.
Some broke springs.
Many of them wore out belts and performance dropped drastically.

These sleds do seem more temperature sensitive than most sleds in the past.

 

[snobyrd]

When i was out a few weeks back with both our axys, it was above 0 deg c ,both sleds were low on rpms, im thinkin a reflash would correct this issue.

 

[sledneck_03]

On a trip we were in melting temps. Axys sleds as well as my pro were waivering. Just did the skidoo thermo on my pro and it was holding 111 but 8200 then jump down to 7900. Im running mds and i pulled .8g i was going to pull another .8 but sled was still rocking after i stopped looking at the tach.

A friend with a 2.6 axys with a 3" saw tooth noticed the same but he has a head and pipe. A stock axys with us dropped 2g as he wasnt seeing peak either.

 

[snobyrd]

On a trip we were in melting temps. Axys sleds as well as my pro were waivering. Just did the skidoo thermo on my pro and it was holding 111 but 8200 then jump down to 7900. Im running mds and i pulled .8g i was going to pull another .8 but sled was still rocking after i stopped looking at the tach.

A friend with a 2.6 axys with a 3" saw tooth noticed the same but he has a head and pipe. A stock axys with us dropped 2g as he wasnt seeing peak either.

My pro drove me nuts with rpm fade, i tried many clutching configurations and couldnt get it sorted.

 

[green_denali]

rpm fade

read this thread, could be your exhaust valve cable


http://www.snowest.com/forum/showthread.php?t=410297

 

[tincuprider]

Just talked to the dealer and they say they have had some exhaust valves sticking from all the oil.
He also said they sold 240 Axys sleds and have lost only one motor. Said they found the primary clutch was horribly out of balance on that one from the factory.

 

[dboivin]

my tech at the dealer called me today. said hes been on line with polaris discussing my low idle issues i brought up to him. He said polaris had him update his DW and that i need to bring sled in for TPS reset and mapping changes? guess they fixed the buggy DW tps adjustment? will find out the details when i take sled in this week. not sure if its a fresh mapping or my dealer hasn't updated is software recently. He did say polaris was aware of low idle issue, tps out of adjustment issues and that this was some of the fixes in the update.

i also had rich running sled when i was out west. temps were in 20°F range at 9,000-11,000'..and my sled idled low and was terribly rich. It literally would burn my eyes if we idled in one spot for more thant 15 seconds. I never had rpm issues tho but did have a burble on bottom almost the whole time i was there. I pulled 8350 pretty consistently.

 

[snobyrd]

My tps was out, dealer adjusted it for me, i also can complain about rich fuel map, im leaving a puddle of gas everywhere, i sure hope we get a updated ecu flash in 17.

 

[Jayxcr]

I was told that on the Axys mapping that it does not adjust past a certain point for intake temps, which are much warmer than actual outside air temps. So it stops leaning itself down inturn running way rich. I know the Bully Dog tuner fixes this but it's not cheap. I was noticing the same thing, its normal for R's to drop alittle on warm days but mine dropped lots! Next time I rode it was cold and sled ran awesome again.

 

[sledneck_03]

My pro drove me nuts with rpm fade, i tried many clutching configurations and couldnt get it sorted.

My iq did it too. I cleaned my valves ( first time in 1300 miles lol) and got my clutch serviced. Hope it goes away cause im weary buying an axys and dealing with it on a third sled!

 

[MBR44]

I was complaining about the same thing to my dealer, all of a sudden I lost 400rpm and no snap up top. I took it back 3 weeks in a row and they did nothing. So I went and picked it up from the dealer and took it to another. I took apart the connectors and di-electrode grease and taped them and the dealer flashed the ecu and did a powervalve relearn in 2hours. I gained 500rpm back and it runs like it should. The second dealer Marquette Powersports said they have been seeing this problem frequently this year.

 

[skippy]

I took apart the connectors and di-electrode grease and taped them and the dealer flashed the ecu and did a powervalve relearn in 2hours. I gained 500rpm back and it runs like it should. The second dealer Marquette Powersports said they have been seeing this problem frequently this year.

Glad you got it figured out! So did the dealer ever say what the actual problem was that needed to be fixed to gain the rpm back? Why did they have to reflash the ecu? Thanks

 

[MBR44]

Glad you got it figured out! So did the dealer ever say what the actual problem was that needed to be fixed to gain the rpm back? Why did they have to reflash the ecu? Thanks

They didn't say, just that the power valves and tps has been a problem but easy fix. They wanted to keep it longer but this was the first day of our ride and just got a foot of fresh so I took it and ran. Ran good after a week of beating on it.

 

[tincuprider]

Dealer cleaned the exhaust valves and did the relearn and that did the trick.

 

[oldsno]

What tincuprider didn't tell you he wasn't that happy up high until he changed his weights to slp's...make him explain ha

 

[tincuprider]

Well, as I indicated the real issue was solved with the valve cleaning/ relearn. I was still lower at the 8-10000 foot level than I had been running all season so I put in 62 gram mtx weights with a 2 gram steel river in the first hole. This brought the rpm up to 8300 where I wanted it....brought my smile back.
No question though the really sick issues I had last week were gone before I swapped the weights.