Axys 6850 rpm, won't rev past

[flying frenchman]

My pro never reved in it's life always 7900-8000 no matter what weights were in and slowly got worse 7600-7700. Tried everything. Connecting rod finally went so I think I'm done with it. Maybe.

Sounds like a lot of guys are complaining about the same things on the axys. I was always pissed off cause I never had revs, can't imagine how happy you guys are with your latest and greatest sled.
Seems like you can change everything and still nothing works. I always though it was in the ignition end of it.

 

[TreeThrasher]

Alright so I have a couple updates.

First and foremost, check your exhaust valve cable if you run into anything like this. Mine was broken.

So, not to be deterred we built up a new cable and put it back together. (Which is a trick to pull off, i really recommend getting a new cable from polaris) Still turns 7000 rpm...

So, I jacked it up and ran it so I could watch the actuator. It just opens the valve to the midrange, never opens them all the way. I disconnected the cable for the actuator, pulled the valves wide open and WHAM! 8300

So, it's amazing how perfectly the exhaust valve placement affects rpm. I'm also not sure what the deal is with my actuator not moving the valve to wide open. I am going to take it in and run the re learn procedure on it and see if that straightens it out.

 

[AdrenalineAddict]

I have a 2017 with 1,200 miles that has also turned into a $13,000 dollar trailer weight. Dealer claims everything functions as designed. My sled went from spinning 8,000 r's to 7,400 in one ride. I told the dealer to put the POS up for sale give, I'd give them 10% and I'll go shopping for a good clean 2012. My son runs a 2012 with a 2.6 under it and has outperformed every stock Axy's we've run it against all season. My Axy's sure feels like a power valve problem, but they say everything is working perfectly.

 

[HECKS]

Alright so I have a couple updates.

First and foremost, check your exhaust valve cable if you run into anything like this. Mine was broken.

So, not to be deterred we built up a new cable and put it back together. (Which is a trick to pull off, i really recommend getting a new cable from polaris) Still turns 7000 rpm...

So, I jacked it up and ran it so I could watch the actuator. It just opens the valve to the midrange, never opens them all the way. I disconnected the cable for the actuator, pulled the valves wide open and WHAM! 8300

So, it's amazing how perfectly the exhaust valve placement affects rpm. I'm also not sure what the deal is with my actuator not moving the valve to wide open. I am going to take it in and run the re learn procedure on it and see if that straightens it out.

Did you ended up solving this issue ? As I am having the same problems after installing Jaws pipe and Indy Dan clutch kit.

 

[Murph]

....check your exhaust valve cable if you run into anything like this. Mine was broken.

So, not to be deterred we built up a new cable and put it back together. (Which is a trick to pull off, i really recommend getting a new cable from polaris) Still turns 7000 rpm...

So, I jacked it up and ran it so I could watch the actuator. It just opens the valve to the midrange, never opens them all the way. I disconnected the cable for the actuator, pulled the valves wide open and WHAM! 8300

So, it's amazing how perfectly the exhaust valve placement affects rpm. I'm also not sure what the deal is with my actuator not moving the valve to wide open. I am going to take it in and run the re learn procedure on it and see if that straightens it out.

Broken E-VES cable. Once he put a new cable in and did a re-learn, he should have been fixed.

 

[HECKS]

Thanks.
I've also got engine light on with 173 3 code for the exh. probe temp high voltage - which I will replace. Am I able to clear these codes on my own or does the dealer need to clear them and engine light will disappear ?

 

[Murph]

Thanks.
I've also got engine light on with 173 3 code for the exh. probe temp high voltage - which I will replace. Am I able to clear these codes on my own or does the dealer need to clear them and engine light will disappear ?

Most codes will go out when problem is rectified and sled restarted. Code is stored in ECU and accessed/ cleared by Digital Wrench.

Exhaust probe may have to cycle/ run a few minutes before code clears on dash. There are a couple of MIL errors that need time to reset. On the Pro Ride chassis, I think the EGT sensors was one of them. The EGT sensors like to weld themselves to the threads. Using the box end (closed) of a wrench will get more bite and less likely to round the corners. I always apply anti-seize to the threads on reinstallation.

 

[HECKS]

Most codes will go out when problem is rectified and sled restarted. Code is stored in ECU and accessed/ cleared by Digital Wrench.

Exhaust probe may have to cycle/ run a few minutes before code clears on dash. There are a couple of MIL errors that need time to reset. On the Pro Ride chassis, I think the EGT sensors was one of them. The EGT sensors like to weld themselves to the threads. Using the box end (closed) of a wrench will get more bite and less likely to round the corners. I always apply anti-seize to the threads on reinstallation.

Good to know. I pulled the sensor out 5-6 times yesterday and emery clothed it up every time it was removed, as I was having issues getting out of an area we shouldn't have dropped into with 3ft of fresh snow. Every time I pulled it out it was heavily sooted up.

 

[chuckbernard]

Having the same problem with my 2017 RMK Pro. Removed the belt so it isn't the clutch, just won't rev past 6350 rpm. New exhaust valve cable, new ECU, new fuel injectors, new reeds, new fuel, new EGT sensor. Checked timing with timing light, 18 degrees BTDC with TPS disconnected (as per manual). Timing being correct seems like crank to stator still aligned etc.

Did the original poster ever resolve the issue?

 

[Sheetmetalfab]

Having the same problem with my 2017 RMK Pro. Removed the belt so it isn't the clutch, just won't rev past 6350 rpm. New exhaust valve cable, new ECU, new fuel injectors, new reeds, new fuel, new EGT sensor. Checked timing with timing light, 18 degrees BTDC with TPS disconnected (as per manual). Timing being correct seems like crank to stator still aligned etc.

Did the original poster ever resolve the issue?

You revved the motor without a belt?

I’m glad the clutch didn’t explode this time.

Good luck dodging that bullet next time.

 

[chuckbernard]

Believe me, after 4 weeks of trying literally almost everything and spending over $2000 for parts and labor a blown clutch wouldn't bother me one little bit. Plus, only revving it for a couple of seconds. The sled is a huge paperweight and NOBODY can fix the damn thing. Plus, Was hoping the the original poster would post what fixed his....if it was ever fixed.

 

[Sheetmetalfab]

Believe me, after 4 weeks of trying literally almost everything and spending over $2000 for parts and labor a blown clutch wouldn't bother me one little bit. Plus, only revving it for a couple of seconds. The sled is a huge paperweight and NOBODY can fix the damn thing. Plus, Was hoping the the original poster would post what fixed his....if it was ever fixed.

Compression and or leak-down test?

My buddies 16 lost compression in one cylinder and acted like that.

65-6700 rpm max.

 

[chuckbernard]

Engine shows 110 psi in both cylinders (we are at 6300ft so this seems normal). Leak down test passed as well but I forgot the details but it was done by a local guy.

Also, after going out and looking at the sled again, I realized that I never actually removed the belt like I said above. Was thinking about it so much that I thought that I had done it yesterday. What we did do is put the stock pipe and silencer back on instead of the SLP and it ran exactly the same but I paid more attention to the RPMs. 6650 rpm max. It goes straight up to 6650 and then just hits a wall like the ECU has decided that it will not allow it to go further. Kind of like the original poster mentioned.

Tonight we removed the pipe and inserted a video scope up the y-pipe and examined the exhaust values in each cylinder as we moved the cable to the fully closed, position number 1 (mid) and then position 2 (fully open). Both sides are fully in sync as far as we can see and they move smoothly.

Since there are no mechanical issues compression, leakdown, and ignition timing all checking fine, it just seems like the ECU has put it in limp mode (or similar) but there are no codes indicating any problem so it is not possible to understand why it is doing what it is doing.

Having it hit exactly 6650 rpm it seems more computer controlled (ECU) rather than some random mechanical issue as that would allow overshooting or undershooting that RMP. But, that is just a guess.

Does anyone know how their limp mode behaves? Or, any other things to try?

I also read about the large capacitors but we couldn't locate them at first search. By the way we have good battery for the electric start in the sled and it checks fine.

 

[Sheetmetalfab]

Engine shows 110 psi in both cylinders (we are at 6300ft so this seems normal). Leak down test passed as well but I forgot the details but it was done by a local guy.

Also, after going out and looking at the sled again, I realized that I never actually removed the belt like I said above. Was thinking about it so much that I thought that I had done it yesterday. What we did do is put the stock pipe and silencer back on instead of the SLP and it ran exactly the same but I paid more attention to the RPMs. 6650 rpm max. It goes straight up to 6650 and then just hits a wall like the ECU has decided that it will not allow it to go further. Kind of like the original poster mentioned.

Tonight we removed the pipe and inserted a video scope up the y-pipe and examined the exhaust values in each cylinder as we moved the cable to the fully closed, position number 1 (mid) and then position 2 (fully open). Both sides are fully in sync as far as we can see and they move smoothly.

Since there are no mechanical issues compression, leakdown, and ignition timing all checking fine, it just seems like the ECU has put it in limp mode (or similar) but there are no codes indicating any problem so it is not possible to understand why it is doing what it is doing.

Having it hit exactly 6650 rpm it seems more computer controlled (ECU) rather than some random mechanical issue as that would allow overshooting or undershooting that RMP. But, that is just a guess.

Does anyone know how their limp mode behaves? Or, any other things to try?

I also read about the large capacitors but we couldn't locate them at first search. By the way we have good battery for the electric start in the sled and it checks fine.

Have you swapped the EV relay? (Right above the clutch side shock tower)
(Didn’t see it mentioned in your list)

Maybe the motor mounts are completely blown out?

You are revving it up on a stand? Is there any change on the snow (or grass)?

If you’re primary spring is broken it can hold rpm way low? (Not likely it would hold rpm back on a stand but worth popping the cover to look)

 

[chuckbernard]

Good suggestion. I did finally find the EV relay so at least I know where it is. I'll give that a try but it may take a week to get one delivered. Wish I had a spare sled t swap parts around.

Tried the sled on snow and 6500rpm is it So, no different.

I do have a spare clutch so I'll give that a try as well. But honestly, it just doesn't sound the same, even at idle.

 

[SRXSRULE]

Sure sounds like the exhaust valves are not opening at all.

If I recall, the sled will test cycle the valves all the way open each time you start the sled up. Start the sled with the hood off and see if the actuator is working.

 

[Sheetmetalfab]

Good suggestion. I did finally find the EV relay so at least I know where it is. I'll give that a try but it may take a week to get one delivered. Wish I had a spare sled t swap parts around.

Tried the sled on snow and 6500rpm is it So, no different.


I do have a spare clutch so I'll give that a try as well. But honestly, it just doesn't sound the same, even at idle.

Swap the two relays right next to each other.

One is EV.

One is headlight.

 

[chuckbernard]

Great suggestions with the relays, I dropped the sled off at a new shop and if they can't fix it I'll try this. Eventually I'll have to start swapping out more and more parts until it works.

 

[pindallout]

A buddies 16 was doing this same mid-bog and not pulling the R's. It was throwing different codes related to the exhaust sensors. The dealer replaced everything but the wiring harness... Including stator, coils, ecm, etc.... Lol...... turned out to be two wires rubbed bare causing the computer to throw random codes and do all kinds of "ghost in the machine" types of things. No kidding they replaced everything and then traced every wire in the harness and found the two wires and completely unrelated to the exhaust components. Just food for thought. If you throw every replaceable part at it and it is still doing it, check the wiring harness.

 

[richracer1]

One thing now that the 800HOs are getting miles on them, the EV cable will stretch and cause issues. The actuator will operate correctly, but the valves will not open all the way. I high recommend changing the cable every other year. It's really easy to do and doesn't require a relearn. Last time I bought an EV cable it was around $30. FWIW, when I did the BMP 860 kit in the summer of '16, I had new cases, the original cylinder block and new exhaust valve kit. Just out curiosity, I had the dealer do a relearn and the tech came out and asked if I was having problems as all were with in specifications. Fast forward to the summer of 18, the 860 came out and my spare 800 was put back in along with a turbo. It had the original cases, new crank/rod kit, new cylinder block, original exhaust valves with a new cable and never did a relearn, sled will pull 8300 all day and I've not had any issues with it. One more thing, the EV cable can and will break without you knowing and will not throw any codes but the engine will not rev over 6800-7000 RPM. Only way to check is to disconnect the cable from the actuator and pull gently on the cable.