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Axys rpm fade ?

GoBigParts

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I think we must also consider that this might be an electrical noise issue. Electrical noises will wreak havoc on TPS and VSS signals. Early Cummins diesels and some Powerstroke's have been inflicted with impossible to solve runnability engine/trans control issues only to find out that the electrical system was louder than a Ted Nugent concert. I installed a noise filter on a problematic TPS sensitive Pro 2 years ago. Same fix I came up with on those trucks.

I want to know more about this fix. I have a Pro that goes through regular TPS adjustments.
 

TRS

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I believe your story 100%. And the diagnosis on this is probably going to be very difficult for the affected sleds like yours and I can understand exactly how you feel. I was one of those idiots that snowchecked a 2005 Skidoo RT 1000 back in April 2004. 2 years of runnability issues, pulling my hair out, etc. and the complaint's sound identical.

The "change in engine tone" with lower RPM is the big one in my mind. I'd hope the people that have actually had a loss of RPM on 2005-2015 Polaris CFI's realize they never heard the "change of engine tone" with a worn belt.

This is exactly "one" of the issues we were having in 04-05 and 05-06. I was a little skeptical when I saw the electric exhaust valves on the new 800HO. The Skidoo RT's had notorious issues with theirs in the beginning and this "change of tone" from the motor being reported and accompanied with the loss of RPM's would require adjustment of the valves. Tempermental. I was adjusting valves on a weekly or monthly basis.

Could this be an exhaust valve and/or control issue? Absolutely! DTR has seen it.

The next thing that caused this issue: Exhaust system....mostly silencers that created weird pressure issues which then would cause the exhaust valves to go wacko. You could take a perfectly good running 1000 and put twin pipes on it and have the exact same complaint that these guys are having.

Could this be an exhaust system/pressure/or temp issue? Absolutely!

Tony mentioned a possibility of the electrical system.....Ding Ding Ding....Polaris has been very weak with their electrical systems. Anybody that does driveability work in automotive/transmission and chases wires and sensors for a living absolutely laughs at the Polaris electrical system. We all know how weak the Pro is for available power. Now Polaris has added an electric oil pump ECU Controlled and electric controlled exhaust valves again ECU controlled. This is not the simple on/off exhaust solenoid of the Pro.

So the big question is....What did Polaris do different in the Supplying Power to all of the extra electrical stuff on the 800HO? On this type of system, any type of runnability problem could present itself if there is not enough power/voltage/noise, etc. to run all of the added electrical components. Something the RT 1000 was plagued with as well...intermittent loss of RPM's with everything sound. Major rework of the ground system solved by some guy back east fixed what was causing low voltages, etc.!!!!

I think we must also consider that this might be an electrical noise issue. Electrical noises will wreak havoc on TPS and VSS signals. Early Cummins diesels and some Powerstroke's have been inflicted with impossible to solve runnability engine/trans control issues only to find out that the electrical system was louder than a Ted Nugent concert. I installed a noise filter on a problematic TPS sensitive Pro 2 years ago. Same fix I came up with on those trucks.


Polaris might get lucky and find out this is a mapping issue causing a hot pipe to go cold or remap the opening/staging of the exhaust valves. if so then a simple reflash would take care of it. I also think we should take it easy on the guys that did shell out $14K this year and are having problems.


I was really hoping Polaris (who already builds the best handling and riding machine) would bring us a 21st century electrical system in these sleds. Take a good look at an ETEC and compare. I am convinced if they did, alot of the weird complaints would vanish.

Dave,
Good write up. I believe you are correct. Filters are rumored fix.
The stator and flywheel on the 2015 HO have not been upgraded. They have been the CFI2 production parts since model year 2013.
 
J
Feb 25, 2015
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brand loyal.complain and buy another one.:)

Given my track record with Polaris I feel taking my chances on another Polaris sled "Or Two" should not concern you. Yes. I am brand loyal and surely feel plenty right to vent my displeasure with this last sled. If they could fix it, I would have shut up long ago. Never had problems like this with any of my prior Polaris sleds. If you owned the sled I just traded in you would retract your comments. THX Anyways for your opinion just the same
 
S

snowmobiler

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i was liking the new poo until the fade crap popped up..i like riding to much to buy another problem sled.been there and sat home one winter.LOL.thanks for heads up.:)
 
S

snopromod

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I've always wondered why they don't run their signal wires in shielded jacket? Seems like alot of noise and vibration under hood that could easily disturb signaling before it reaches the ecu.
I wonder if these issues continue if someone should wrap their harnesses in tinfoil then ground one end somewhere to bleed vibration and noise off, if that would help as a simple test.?
 
S

snowmobiler

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the good news is ...the mystery fade is a valid excuse for getting spanked by a non turbo yamaha's next winter...:).
 
A
Dec 27, 2009
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well im from the frt st john bc area i am the only one in all of bc to snow ck the 2015 axys 800 switchback with the new motor , from day one it would foul plugs u would ride for a few hrs shut down over night and next day its not starting 1 plugged fouled after 3 sets i decided a hoter plug so whent to irridume xtreme ngk 8 that fixed the fouling problem for about 1 mounth then one mornin startedup on 2 was running while put snow suit on and then start running on 1 cylinder so at that point i knew it was igntion problem took i to dealer and they checked the capacitators 4 of the 5 where no good so they put 5 new ones in an 2 mounths later just got sledback on april 12 /2015 ofcoarse polaris has no parts at factory. the sled was having rpm issues only once did it ever see 8400 like they are to be some times u would have full throtle and acted like it was out of fuel uback throtle off to 3/4 then i would take off again . will see what next year brings if its still messing around may be put msd ignition in it as far as the sled goes very good chassi , suspenion and ride
 

Thunder101

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Feb 7, 2008
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Interesting for sure. I read Jims 4 or maybe 5 dyno test/write ups and he knows something is up.
Not sure why some guys just like to tell others they dont know $4it.
Once this engine makes it to the hill we will see for sure!

I was pretty hot on this new engine but,,, seems Poo is still sorting their ,,,,, crossed wires out. :face-icon-small-win
 
P

Pro116

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If you want to learn more about this and the guy that is dynoing at dynotech and figuring things out go on www.polarisstarpower.com under the axys section.The majority of dealers didn't have the alignment bar last year or adjust the tps correctly.One othe risssue is oblonged mufler hole where the pipe meets and exhaust leaking.
 
R

Ratchit

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I have a 15 Switchback Axys 800 H.O...

Doesn't seem to be clutching. Run Cool. Downshift is great. Like a light switch from good to bad. Half the day your smiling.. Ripping 8400 rpm then your behind the rest of the gang kicking the bitch wondering where 1000rpm just went. Jeckyl-n-Hyde all the way. Take it to the dealership all you want. Polaris only allows so much testing and they aren't reaching very far. It's funny listening to people make short of the issue and put faith in Polaris that they have it under control. They surely haven't been able to help us 2015 Axys HO buyers. The whole season has passed us by and we still have F*cked up sleds. ALL OF US!

Go to: hardcoresledder.com and read the RPM threads on the Axys Switchback/Rush forum. Don't listen to this Troll. Read a little and pass judgement later. It is an amazing motor when on its game. Unfortunately for me it has been 80% Jeckyl and 20% Hyde. ((HYDE SUCKS!!))
I've read all the bs posts on hard core blower. All speculation and hearsay.
Now, maybe you should ask someone that has dyno'd 2 of these at dtr and seen others dyno'd.
I've tested these and have posted extensively in psp about this.
it's not fade, the internet chatter on hardcore blower guys called it that.
it's rpm drop/ rpm loss.
 

GoBigParts

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Given my track record with Polaris I feel taking my chances on another Polaris sled "Or Two" should not concern you. Yes. I am brand loyal and surely feel plenty right to vent my displeasure with this last sled. If they could fix it, I would have shut up long ago. Never had problems like this with any of my prior Polaris sleds. If you owned the sled I just traded in you would retract your comments. THX Anyways for your opinion just the same

To me it is not the brand it is the chassis. Yes Polaris has it right now and it s that good to put up with a few minor other issues not related to chassis.
 
J
Feb 25, 2015
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I've read all the bs posts on hard core blower. All speculation and hearsay.
Now, maybe you should ask someone that has dyno'd 2 of these at dtr and seen others dyno'd.
I've tested these and have posted extensively in psp about this.
it's not fade, the internet chatter on hardcore blower guys called it that.
it's rpm drop/ rpm loss.

I really don't care what you want to call it... Fade, Drop, Loss or Hardcore Blower BS. Really don't care what you want to name the problem. Problem is that the dealer couldn't fix it and Polaris had no answers for it!! 2300 miles of riding this past season and still no fix. I suppose I should have brought it to a dyno guy and spend a few bucks out of my own wallet to find the answer. Thanks for all the great info. Your almost the best.:second:
 
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