cant stand the darting!!!!!!,,!

[kennyspec]

Hey just picked up a 08 nytro 121" its bone stock. Got it for the wife. Only problem is that it darts real bad in the trails and just doeesnt feel stable at higher speeds. I'm looking to make the front end a little less "aggressive" for her. I own a 08 mtx 156" and it feels like a completely different machine its very stable in the trails and doesn't dart at all.

I have done the upper ball joint mod, set the toe to 3/4" out and cranked up the center shock to take off some ski pressure. Nothing seems to work.

On my sled I converted it to a 05 fusion steering post with the knuckle in it to make a more vertical post similar to the oft relocate kit but a bit more extreme. What I did notice was that the distance from the center of the steering shaft to where the tie rod would connect is shorter on the fusion shaft compared to the Yamaha shaft. This basically translates into needing to turn the bars more in relation to the amount that the skis turn. I wonder if I was to weld up the hole on the Yamaha shaft where the tie rod would mount and re drill it a bit closer to the center of the shaft if this would reduce the darting? Basically giving you more leverage at the handlebars? Thoughts?

 

[sxrviper]

I ride an 08 nytro rtx and here is my settings that i find are good for stock skis.
Fox Float at 45psi
More preload on center shock (roughly half of the threads)
Front Limiter out all the way
Also i repositoned the rear coupling blocks further back on rail (drilled new holes)

 

[SDXTXrider]

I rode my XTX once and felt it was almost dangerous on the trails because of the darting. I put a set of Simmons Gen 1 skis and now it handles like it's on rails and is a ton of fun!

 

[603NytroXTX]

I rode my XTX once and felt it was almost dangerous on the trails because of the darting. I put a set of Simmons Gen 1 skis and now it handles like it's on rails and is a ton of fun!

SIMMONS!!!!!!!!!!! I have been riding them on Yamaha's for years now and i absolutely love them. Wouldnt go any other direction. I just bought a pair of new gen 3's for my xtx.

 

[yamaha1973]

The new tuner skis from Yamaha seem to do the trick, and there relatively inexpensive.

 

[kviper]

Semi aggressive snow Tracker's, set toe to 0" with a strap across the ski tip's and no shim's under the rubber bumper's. Problem gone!!! And it will still turn when you want it to.
I have them on both of my Phazer's and my 12 Apex and they are the chit.
They are not cheap but they wear very well and they work!

 

[kennyspec]

So new skis should do the trick. It almost seems that at high speeds the steering is too "sensitive" like a tiny change in turning the bars make the skis turn too much and the sled is uncontrollable.

 

[Apex2006]

Anything but the stock skis! I have the 08 and 09 and both went dartless after I went with C&As.....

 

[grizztracks]

Simple fix for darting is to install Studboy deuce bars 4.5" and set toe out to 1/2" total. Shimming the rear of the ski rubbers aproximantly 3/16" will also help but not completely necessary with the deuce bars.

 

[AKrider]

That's just how it is, I don't care what you do with the stock front end you will never eliminate the darting 100%. If I were you I'd save up some money for some aftermarket spindles as I think those will be the most bang for the buck. Still, I'd wait to read some ride reports before spending the $300 on SLP spindles. You could go with some used '09 or later stock spindles that will help calm down the front end. They will require the shorter '09 tie rods but you might get lucky and be able to turn the stock ones in far enough. I'm not 100% sure the longer '08 tie rods will work though. The '09 spindles have different geometry that will reduce the darting but they aren't perfect nor a dramatic improvement so I would not spend the money on brand new stock spindles. You already did the upper ball joint mod so '09 or later spindles will basically give you Yamaha's "improved" FX2 geometry.

Deuce bars will cut down on the darting but then the front end pushes in the corners. I bought them and hated how they felt and handled for aggressive riding. Different skis can actually make the darting worse. I spent a small fortune on different aftermarket skis and tried skis off other sleds that I'd ridden and knew handled well. Different skis don't work period. One company in particular claimed to have the cure for the Nytro early on and heavily promoted their product. I bought their skis and low and behold they didn't cure the darting ether. Eventually I found a skid and suspension set up that worked best for my riding style, needs, weight and snow conditions I discovered my sled was the most predictable and lightest steering with the stock skis that most everyone hates. I then discovered I actually liked the deeper keel Nytro RTX skis with 6" shaper bars the best when it came to high speed running on set up trails. Those skis delivered plenty of bite in the corners, had a light feel at the bars and were less susceptible to darting than any other ski and could still work for aggressive riding. I think this is why it took Yamaha so long to come out with a different ski even though everyone was clamoring for a different skis because on most every other sled, skis make a dramatic improvement in handling. The downside is when used off trail the stock skis are too narrow and knife in so they are worthless. But, in those conditions darting isn't much of an issue so if you ride off trail a lot, take your pick of whatever ski is wider and has a color and shape you like.

It sounds like your repositioned handlebars are making the problem worse because you are putting even more weight onto the front end. The Nytro is too front heavy stock and I know the handle bar swing sucks. The OFT relocator works quite well at getting the swing to feel more natural and the sled feels a lot better though the bumps. The only downside it is it brings you a bit more forward and puts more body weight on the front end. Still, that compromise is worth it for the additional control you gain through the whoops. If you aren't into bashing bumps I think you are better off moving the post back to the stock location.

Play with your sled and do a bunch of searching and reading and you will improve it but that's not really saying a lot. The handling sucks something terrible and the best you will get out of the stock front end is a sled that handles half as good as most any other modern sled that has been produced in the past 5 years. I don't mean to be a downer but it is pretty bad when my daughters 12 year old Indy Lite 340 can be ridden down the same trail with far less drama, more control and no darting compared to the Nytro.

 

[iwillwait4u]

I had my stock skis work with no darting First flip your ski rubber around and then install a quarter inch shim under the ski rubber and fixed cheaper than skis!! I could run 80 mph with one hand! for more details look at chttp://www.bergstromskegs.com/site.htm click on testamonies for the nytro. If you want to get rid of darting 100% with stock skis this will do it!!

 

[00-NUKE]

Hey just picked up a 08 nytro 121" its bone stock. Got it for the wife. Only problem is that it darts real bad in the trails and just doeesnt feel stable at higher speeds. I'm looking to make the front end a little less "aggressive" for her. I own a 08 mtx 156" and it feels like a completely different machine its very stable in the trails and doesn't dart at all.

I have done the upper ball joint mod, set the toe to 3/4" out and cranked up the center shock to take off some ski pressure. Nothing seems to work.

On my sled I converted it to a 05 fusion steering post with the knuckle in it to make a more vertical post similar to the oft relocate kit but a bit more extreme. What I did notice was that the distance from the center of the steering shaft to where the tie rod would connect is shorter on the fusion shaft compared to the Yamaha shaft. This basically translates into needing to turn the bars more in relation to the amount that the skis turn. I wonder if I was to weld up the hole on the Yamaha shaft where the tie rod would mount and re drill it a bit closer to the center of the shaft if this would reduce the darting? Basically giving you more leverage at the handlebars? Thoughts?

AKrider is correct that the 08 Nytro's handeling is bad. IMO: I think it is quite possibly the worst handeling snowmobile EVER straight out of the crate. When I had my 08 the 2 biggest improvements that I found was the OFT relocator and the ball joint mod listed in the Totallyamaha FAQ's.
Little things you can do to help this include:
1. Spinning the rubber ski boot around so the thicker end faces the back
2. Anything other than the stock ski's will help too. (I went as much as buying tripple blade carbides to make the stock skis work and they still sucked.)
3. If the rubber boot is already spun around and it still darts, you can add shimms to the back bottom underside of the rubber ski boot to take pressure off of the toe.

 

[kviper]

I have been down this road a million times!
The only thing I found (and I spent a but load on ski's, bar's and different set ups) that will 100% eliminate dartin/tracking is snow Tracker's on stock ski's!! And they are cheaper than any ski and wear bar set up including the new tuner's.
Dual keel ski's will dart/track as well if you come across another dual keel that rode in front of you and they will also cost you some top end and MPG.
I'am sure there are others in here that have run them on Nytro's that said the same thing.

They completely settle the front end and still corner and don't push like dually's, deuce bar's etc. You won't Believe it's the same sled!

 

[grizztracks]

I agree that the deuce have a slight push in corners but they are more predictable than some other ski carbide setups I've tried. I was able to make the deuce bar setup work fairly well on a 08 RTX. I've since gone to Curves but still run the deuce bars on the wife's Vector and she's happy with them. Being that he's trying to correct darting for his wife's sled which is most likely not pushed to the limits, the deuce bars are a good cheap and easy fix for less aggressive riding. style.

 

[Beenba]

Cobra Head 6" Carbides did it for me with stock ski's. I actually bought the sled with them already installed. Handles great IMO with not too much steering force or push in corners. I am looking at getting the new tuner ski's though, only because my stockers are getting beat up.