After seeing a few mentions of spindle swaps, and lack of good replacement Nytro spindles, I decided to try Polaris Axys RMK spindles on my sled. Hopefully this helps others.
I chose to cut and reshape the bottom of the RMK part, and retain the use of my Yamaha ski rubber. Otherwise I only had to press a sleeve into the steering mount to reduce from 10mm to 8mm.
To keep the arm geometry right, I added a steel spacer on top, and a couple washers to shim the lower ball joint. Pretty simple, just keeping things from binding. If anyone wants details on bolt lengths I can update this.
What most are probably asking at this point is why, or what benefit is there. I can tell you these parts are beefy, especially around the lower ball joint where the Nytro spindles have a weaker design. They’re also a bit taller, but place the ski pivot behind the Nytro spindle in relation to the steering pivot. This “trail” in the geometry could steady the steering. Couple that with a longer steering mount, and the steering effort decreased. Plus the ski stance is widened, just a little.
Hopefully this helps others to improve their sleds.
Stubbs
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Can you take a pic from the front of the sled? Really interested in how the steering tie rod angle compares to the lower a-arm angle with those Polaro spindles. Would be nice to see them bolted up to the stock arms as well for comparison.
I don’t have a pic from the front handy, but this might help. Note that the steering mount of the Nytro spindle lines up closely with the bottom of the RMK spindle. The tie rod is kept in nearly the exact same location.
Perrdog
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I have a set of JRE spindles that were on my 11 nytro? if anyone is interested...
We have a classified section for selling.
Stubbs
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Agreed, geometry looks pretty good from that pic.
FarbeyondDriven
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You still have these?
Perrdog
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yep, pm
Time for an update. The taller Axys RMK spindles really work well. I’m really happy with how stable my Fx Nytro has become, and the steering effort is improved as well. Just wish the rear suspension could keep up with the front on rough trails.
CarWashGuy
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Hi Kurt
Going for it on my 12 Nytro. I bought 15 Indy XC SP spindles and matching skis. Figured the ski geometry would work out with matching skis.
Sticking with original a-arms. Curious if you can share spacer sizing for the upper ball joint and lower and any tips on tie Rod connections.
Really appreciate anything you can share.
Sean
Sean,
I hate to Break this to you, but the 2015 Indy SP uses the older suspension design with shorter spindles and different geometry for the steering mount. You may encounter excessive bump steer. I looked at them briefly when I researched my swap, and decided against them. The newer Axys chassis spindles were a better match. They come in two lengths, as well.
CarWashGuy
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Length is debatable. I know some like the shorter Axys ProS spindles, to keep the ski pressure a little light, reducing darting but maybe not as hard carving. I prefer the taller Axys Pro RMK mountain sled spindles, which raise the front a little, and give more ski pressure and sharp handling with my Skinz Concept a-arms (42” stance, +5” forward). I have 12mm spacers above the spindle, to maintain arm geometry.
On a side note, the front works much better than the rear. So much, that I swapped a skidoo rMotion skid into my Nytro. Going to the Soo-500 Saturday, and test riding Sunday.
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CarWashGuy
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Thanks again Kurt
Found these for a good price so I’ll have both options. Gonna try the short ones just to get back on the trail. Once I dial in the front, I’ll worry about the rear (Hey-O).
Agree Doo’s R-Motion is gonna be awesome. My buddy has a Polaris rush with their version and it’s an awesome rear skid.
A lot of people want to know about what we’re doing. I’m considering publishing the “recipe” with part numbers and specs to help other Yamaha fans. Sounds like you’ve cracked the code.
Have a great run on the Soo, wishin I was in Michigan. Let us know how it goes!!!
Found these for a good price so I’ll have both options. Gonna try the short ones just to get back on the trail. Once I dial in the front, I’ll worry about the rear (Hey-O).
Agree Doo’s R-Motion is gonna be awesome. My buddy has a Polaris rush with their version and it’s an awesome rear skid.
A lot of people want to know about what we’re doing. I’m considering publishing the “recipe” with part numbers and specs to help other Yamaha fans. Sounds like you’ve cracked the code.
Have a great run on the Soo, wishin I was in Michigan. Let us know how it goes!!!
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