2017 RMK 8300rmp down to 7700rmp with elevation. Why?

Ktmsx350f · Apr 12, 2018

Big10inch said:
Well my Axys blew the motor well before 1400 miles. It also needed a primary clutch rebuild, motor mounts and a power valve cable. You share your experience, I will share mine...

I think the motor is toast by 1400 miles. If you look around, I am not alone with an Axys motor failure.

Very few have issues with that low of miles. I have 3 all with more miles then yours zero issues 2 have turbos. 3 more in our group same no signs of issues at all. All rode hard and put away wet. Any engine can fail and all 2 strokes will have some failures but the Axys is a very reliable engine. I wrench on a lot of sleds close to 100-150 a year on the side and have year to see a Axys fail. Our local dealer sold a **** load and this town is full of Axys and they have not done a failed axys engine yet

Big10inch · Apr 13, 2018

Ktmsx350f said:
Very few have issues with that low of miles. I have 3 all with more miles then yours zero issues 2 have turbos. 3 more in our group same no signs of issues at all. All rode hard and put away wet. Any engine can fail and all 2 strokes will have some failures but the Axys is a very reliable engine. I wrench on a lot of sleds close to 100-150 a year on the side and have year to see a Axys fail. Our local dealer sold a **** load and this town is full of Axys and they have not done a failed axys engine yet

and yet there are almost dozen blown up poo motors listed just in this thread. Enjoy your head in the sand time...

revrider07 · Apr 13, 2018

Imo a lot boils down to warranty got it ride it like I stole it maintenance who cares I got warranty. I know in deep snow I could grenade any two stroke motor made today in less than five hundred miles. But I don't like to break down in the backcountry if I can avoid it. Kind of like my Miller 250 welder has a duty cycle that's not continuous.

aksledjunkie · Apr 13, 2018

Soooooo, back to the matter at hand, have you had any luck with your sled and pulling RPM or checking any of the above mentioned OP?

Teth-Air · Apr 14, 2018

Let us not forget about mapping. Last season my Axys lost 200 rpm from one day to the next when the weather changed drastically. There is likely more to it that Poo changed the T-stat and head on the 18 to run these motors cooler. They said it was for consistency. We have also experienced first hand that the TPS can seem to magically change it's setting in one ride. The base voltage and idle voltage must be tested regularly if there are any performance issues. While you are checking the TPS, pull the airbox most of the way out so you can see in to the throttle bodies. Make sure the butterfly valves are set equally. Mine where not and think the linkage wore or the adjustment screw came loose. On high kilometreage sleds also check the exhaust valve bushings. They wear bad and can stick the valves. Finally if your sled has dropped below 120 psi compression, say 110ish, you will be down in power a bit.

eyefish123 · Apr 15, 2018

I am starting to question the mapping also. You don't see much about the 2018s with the RPM issue. I have tried clutching, Seafoam, new EGT sensor, motor mounts, adjust TPS, etc. Some have fixed problem for a ride or two and then right back to 7,900 to 8,000 RPM. I am not losing enough RPM to really hurt anything but I paid for 8,300 RPM and I would like to get it out of my motor. My riding partner has a 2018 and pulls 8,300 RPM all day long in any snow conditions. Starting to get tired of this.

Teth-Air · Apr 15, 2018

eyefish123 said:
I am starting to question the mapping also. You don't see much about the 2018s with the RPM issue. I have tried clutching, Seafoam, new EGT sensor, motor mounts, adjust TPS, etc. Some have fixed problem for a ride or two and then right back to 7,900 to 8,000 RPM. I am not losing enough RPM to really hurt anything but I paid for 8,300 RPM and I would like to get it out of my motor. My riding partner has a 2018 and pulls 8,300 RPM all day long in any snow conditions. Starting to get tired of this.

Some of the 16's we ride with do hit 8200 - 8300 rpm all day long. Start by checking compression first as if it is down any it will be noticed firstly by rpm loss. Sure you can run lighter weights but you will then lose track speed. Also don't forget if you are comparing a quick-drive sled to a chain-drive sled there is a big difference in gearing and that alone can result in rpm differences because they are clutched the same and tall gearing can load the motor more.

snosumitcsr · Apr 15, 2018

Try a new belt for sure, belts glaze and look fine, but are toast. Had this problem before, I changed weights and no change. New belt bam fixed

Sage Crusher · Apr 15, 2018

Teth-Air said:
. Finally if your sled has dropped below 120 psi compression, say 110ish, you will be down in power a bit.

But also keep in mind elevations- as an example 8,000' peeps will show less compression than the flatlanders....

Reddragon800 · Apr 16, 2018

I took my 2016 axys motor apart on the weekend to see how everything looks. I have just under 1600 miles and it looked very good. Crank was rock solid. No piston wear, and the cylinders were perfect. I gave it a hone and threw in a Wossner fix kit. The added compassion and case volume should be good for 2-3 hp. the Wossner pistons were 100 grams lighter than stock. The axys piston also has 2 different ring sizes, where the Wossners were both larger and spaced further apart.

Teth-Air · Apr 16, 2018

Reddragon800 said:
I took my 2016 axys motor apart on the weekend to see how everything looks. I have just under 1600 miles and it looked very good. Crank was rock solid. No piston wear, and the cylinders were perfect. I gave it a hone and threw in a Wossner fix kit. The added compassion and case volume should be good for 2-3 hp. the Wossner pistons were 100 grams lighter than stock. The axys piston also has 2 different ring sizes, where the Wossners were both larger and spaced further apart.

I know i'm pretty compassionate too but could never muster up that extra 2-3 hp. The Doo guys usually find it after drinking their Doolade though.

polaris dude · Apr 16, 2018

Big10inch said:
and yet there are almost dozen blown up poo motors listed just in this thread. Enjoy your head in the sand time...

When it is 2-3 people who have each blown 4 engines each doesn't it make you wonder how everyone else is doing fine?

But I'm sure for you personally it is because you ride so much harder than anyone else right Mr. big10incher?

Big10inch · Apr 17, 2018

polaris dude said:
When it is 2-3 people who have each blown 4 engines each doesn't it make you wonder how everyone else is doing fine?

But I'm sure for you personally it is because you ride so much harder than anyone else right Mr. big10incher?

I never said that. The problem is, as a normal rider, I couldn't get more than one season out of my last three Polaris sleds without major issues. I am sure it is because I am a massive stud like you say... OR, it could be because Polaris quality and support sucks...

If you take your blinders off and start looking, the truth is out there, even in this heavily biased section of the forum.

Can you explain to me why the Cat and Doo forums do not have threads about almost new motors consistently losing rpm? It is happening to almost everyone riding an Axys...

Here is the list of things this poor guy needs to consider on his almost new sled, common Axys issues...

primary clutch, eats rollers like a baby on candy
motor mounts, looser than the whore in your kitchen
power valve cable, snaps like a twig in the wind
TPS, where to even begin.... adjust it, replace it, curse it
electrical relays, probably sourced from a 70's Jaguar
compression, this motor is a barely improved version of what came in the Dragon, good for almost 500 miles....

I am probably forgetting a few but, a laundry list of major rideability issues follows only ONE of the manufacturers today. Defend them all you want but, it only makes you look foolish.

Truth is, it isn't my big 10 inch at all. I simply can not afford to have a new spare so I don't miss ride time while my sled is in the shop. I love the chassis, that is why I tried so hard to stick with Poo but, truth is, the durability just isn't there and, I can't afford that, money wise or time wise. Good for you if you can. I have plenty of fun on another brand, more, because I don't have to worry about it exploding anymore...

TRS · Apr 17, 2018

Big10inch said:
I never said that. The problem is, as a normal rider, I couldn't get more than one season out of my last three Polaris sleds without major issues. I am sure it is because I am a massive stud like you say... OR, it could be because Polaris quality and support sucks...

If you take your blinders off and start looking, the truth is out there, even in this heavily biased section of the forum.

Can you explain to me why the Cat and Doo forums do not have threads about almost new motors consistently losing rpm? It is happening to almost everyone riding an Axys...

Here is the list of things this poor guy needs to consider on his almost new sled, common Axys issues...

primary clutch, eats rollers like a baby on candy
motor mounts, looser than the whore in your kitchen
power valve cable, snaps like a twig in the wind
TPS, where to even begin.... adjust it, replace it, curse it
electrical relays, probably sourced from a 70's Jaguar
compression, this motor is a barely improved version of what came in the Dragon, good for almost 500 miles....

I am probably forgetting a few but, a laundry list of major rideability issues follows only ONE of the manufacturers today. Defend them all you want but, it only makes you look foolish.

Truth is, it isn't my big 10 inch at all. I simply can not afford to have a new spare so I don't miss ride time while my sled is in the shop. I love the chassis, that is why I tried so hard to stick with Poo but, truth is, the durability just isn't there and, I can't afford that, money wise or time wise. Good for you if you can. I have plenty of fun on another brand, more, because I don't have to worry about it exploding anymore...

The truth is written here in black and white.
I’ve always said if you ride a Polaris you better have two.

Reg2view · Apr 17, 2018

Poo knows they still have a motor issue, that's what the 850 is really all about. 800ho was just an OEM fix kit.

Each of the OEM's do move even slower now with the big investments they make in chassis and motor tooling, R&D, branding, and the thin margins that get driven by weather. Makes the ORV biz look like a lemonade stand. First year sleds are almost always problematic (you can say never buy a first year cat, but all the OEMs have struggled with totally new chassis+motor Y1 big bores the past 10 years). And the fixes are taking longer and longer. It's why we'll see fewer/no new chassis/motor combos, alla the 2017 850 Summit, ever again. Totally new motors will use an existing chassis, and vice-versa, whenever possible for at least the next five years, and maybe longer. Doesn't mean you shouldn't have a backup sled...

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2017 RMK 8300rmp down to 7700rmp with elevation. Why?

Ktmsx350f

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Big10inch

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revrider07

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aksledjunkie

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Teth-Air

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eyefish123

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Teth-Air

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snosumitcsr

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Sage Crusher

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Reddragon800

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Teth-Air

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polaris dude

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Big10inch

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TRS

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