I see countless posts on the running issues of the 2015 axys,Dropping rpm, over on the hcs forums. Seems like there's a lot of frustrated people. I want to sno check but this worries me a lot. And the fact that they aren't having demo rides worries me even more that this thing isn't figured quite out. Any one else have this concern?
Axys rpm fade ?
- Thread starter dexter
- Start date
This topic was addressed on a post a couple weeks ago. Just search "fade" and you'll find that. Some good information. It is a concern. You like to assume that they'll address it, but having fought similar issues with Cats over the years, it can be a headache and the dealers may not be in a position to help.
C
Carls Cycle
Basic Member
RPM Fade
You cannot compare the two sleds, as they are setup completely differently. The problem is most likely a clutching issue from what I understand of it, and the clutches and belt are completely different from the 2015 to 2016. And not a lot of them had the issue, so until it happens to pop up, I wouldn't let that worry you. These sleds will be a vast improvement over the Pro, which is amazing to think of since the Pro is an amazing sled in it's own right!
You cannot compare the two sleds, as they are setup completely differently. The problem is most likely a clutching issue from what I understand of it, and the clutches and belt are completely different from the 2015 to 2016. And not a lot of them had the issue, so until it happens to pop up, I wouldn't let that worry you. These sleds will be a vast improvement over the Pro, which is amazing to think of since the Pro is an amazing sled in it's own right!
G
greasemonkey3406
Well-known member
There seem to be two different issues:
1. Low rpm all the time due to clutching or other issues.
2. RPM fade where the sled will rev to over 8100 rpm and then drop down to around 7700-7900 rpm and sometimes as low as 7400 rpm. They say sometimes it takes a few miles to happen and it is almost like someone is flipping a switch when it happens. The tone of the engine even changes. This issue is not a clutching issue because people have swapped clutches, springs, weights, belts, checked deflection and alignment and it didn't solve anything. Some are saying it is caused by air pockets in the cooling system, tps settings, exhaust valves not opening all the way or maybe the ecm is running in some sort of protection mode that no one knows about.
1. Low rpm all the time due to clutching or other issues.
2. RPM fade where the sled will rev to over 8100 rpm and then drop down to around 7700-7900 rpm and sometimes as low as 7400 rpm. They say sometimes it takes a few miles to happen and it is almost like someone is flipping a switch when it happens. The tone of the engine even changes. This issue is not a clutching issue because people have swapped clutches, springs, weights, belts, checked deflection and alignment and it didn't solve anything. Some are saying it is caused by air pockets in the cooling system, tps settings, exhaust valves not opening all the way or maybe the ecm is running in some sort of protection mode that no one knows about.
More conjecture that this is a motor mount material issue causing the fade, hosing up clutching. Mounts are wearing rapidly, material going soft. Evidence is mounting, so to speak. It wouldn't be the first time with this issue for Poo in recent years...
I am a little more than concerned about this because I have had new model sleds before that did this kind of thing and the issues were never resolved. From what I'm reading this isn't sounding like a clutching issue to me. Hopefully polaris has this figured out by next year because I want one, but I'm worried they won't.
Well mine is already ordered. Is it a problem in the 15 sleds? Yes, but not all. If it is clutching, it may be a complete non issue in the RMKS as they are setup completely different. If it is a reflash, I have confidence that polaris will have it figured out before my four year warranty runs out.
Bottom line, I wouldn't fret it. If you are worried, the solution is simple: don't buy one.
Bottom line, I wouldn't fret it. If you are worried, the solution is simple: don't buy one.
S
swrev
Well-known member
Any chance Polaris can/pipe combo is to tight? Stock is usually best for back pressure, but if it is little to tight for the trail sled, could be perfect for the mountain.
On an older Doo of mine, I had a can that was too tight and it created a incredible bottom response but fade would get worse the more you ran it. Chased clutching to no end, switched can and ran good. It did not show up like some of the cans where you install them and rpm is off right away and going back to stock was a big improvement. Thus why I kept after clutching.
Haven't followed any Axys turbo builds but if the pipe is to tight, they should be picking up tuning issues w/ excess heat and have piston crown issues.
On an older Doo of mine, I had a can that was too tight and it created a incredible bottom response but fade would get worse the more you ran it. Chased clutching to no end, switched can and ran good. It did not show up like some of the cans where you install them and rpm is off right away and going back to stock was a big improvement. Thus why I kept after clutching.
Haven't followed any Axys turbo builds but if the pipe is to tight, they should be picking up tuning issues w/ excess heat and have piston crown issues.
J
jmaxdox
Active member
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!!))
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!!))
J
jhillam
Active member
Subscribe to DynoTech and read articles or call the author. It is definitely not a clutch issue. I've talked to guys back east on the phone and they are seeing different compression from one sled to the other. DynoTech Jim confirms that the exhaust port opening is not consistent from one machine to the other. Horespower numbers in controlled tests are all over the board from one test to the other. It seems the few culprits are:
1) hard-surfaced rings not seating consistently with differing break-in procedures--some guys are pulling jugs to hone;
2) throttle position sensor voltage not being set properly on every machine;
3) exhaust valve operation not being consistent and some of the sleds going into a mode closing down exhaust ports at WOT--this appears to be primary culprit to rpm fade.
4) differing reed tensions on 3rd party V-Force reeds
This is an exciting new engine with lots of promise to make us all smile, but it is not a 160 HP engine. There was one test accomplishing this with cold air and a factory supplied ecu box with programming differing from anything tested off the trail. Look for 150 HP and the fastest 150 HP we've felt at that.
1) hard-surfaced rings not seating consistently with differing break-in procedures--some guys are pulling jugs to hone;
2) throttle position sensor voltage not being set properly on every machine;
3) exhaust valve operation not being consistent and some of the sleds going into a mode closing down exhaust ports at WOT--this appears to be primary culprit to rpm fade.
4) differing reed tensions on 3rd party V-Force reeds
This is an exciting new engine with lots of promise to make us all smile, but it is not a 160 HP engine. There was one test accomplishing this with cold air and a factory supplied ecu box with programming differing from anything tested off the trail. Look for 150 HP and the fastest 150 HP we've felt at that.
I heard today it's a fluctuating voltage problem causing the ECU to shut down. Sounded like they are going to add capacitors to smooth volatage drops/spikes.
Maybe they need to improve/upgrade the charging system. The added electronically activated engine controls may be compromising the power to the ECU.
Maybe they need to improve/upgrade the charging system. The added electronically activated engine controls may be compromising the power to the ECU.
From what I have read it sounds like something is causing the exhaust valves to not always open all the way, not sure if its the actuator or the ECU. They took a sled with fade and tied the valves wide open and the fade disappeared. Polaris knows about it and I think they will have the glitch figured out for next season.
Just a thought; are the electric start sleds not seeing this phenomenon? The battery as I see it should cushion the demand on the stator at the peak draw times right? (I'm not electronically savvy so I may well be making assumptions that do not hold up in actuality, sled may not be wired to borrow from the battery during those times) just a random thought as I perused the thread. Are the battery equipped sleds seeing the same thing or is it just the battery less, manual start models?
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Sleds
I would guess they are getting it figured out, may top riders are riding the axys rmks like crazy the passed few weeks so I would guess the bugs will be all fixed.
we sold a few short tracks last year with no issues so far so I don't think its a widespread issue
I would guess they are getting it figured out, may top riders are riding the axys rmks like crazy the passed few weeks so I would guess the bugs will be all fixed.
we sold a few short tracks last year with no issues so far so I don't think its a widespread issue
M
minus40
Well-known member
Thanks for that. I own a 15 800HO switchback. First ride blew a capacitor on the lighting, handwarmer circuit. After I had one afternoon with rpm loss from regular 8350 to 7600. Next day back to normal. After that fighting inconsistent rpm. Will lose 100- 150 rpm after first hour give or take.
Sleds a blast to ride, engine performance...not so much
