Just finished Installing clutch rivets, still overreving

[russellrox]

Just finished taking my nytro mtx for a rip to check out if the weights that I installed fixed my overreving problem. It's still overreving and lightly hitting the limiter when held wide open, The sled has 2000 km 's on it, I tried my spare belt but no change. My weights had no rivets in them at all just 3 blank holes, I installed the rivets closest to the bolts that hold the weights in place. Anyone have any other ideas, frustrated with this thing.

 

[08nytromtx]

What is your elevation?

 

[russellrox]

like 2300ft,

 

[08nytromtx]

I'm just under that and here is my setup. I have the same problem you do and here is what I found. 22/40 gearing, blue:brown:blue primary spring, and 17.2 gram rivets on the inside and 13.3 in the outer 2 holes. Should fix your problem. Did you take the primary off to add your rivets?

 

[russellrox]

no just the outer cover, I don't want to regear the sled, hopefully I don't have too, I just want it to stop hitting the limiter.

 

[08nytromtx]

Unfortunately you might have to. Our sleds come set up for 10,000 ft from the factory. I have just the gearing changed currently and it helped somewhat but still at wot from a stop, I hit the rev limiter so now I'm gonna do the clutching. Is it fairly easy to change the weights and springs with just the cover off?

 

[mike306]

I am haing the same issue with my Nytro MTX im at 1500 ft, i can only get 110km/h out of mine with it hitting the rev limiter. i bought the sled from a guy in the mountains and am now looking for a setup that will work for me. Anybody have any info?

 

[russellrox]

I will be taking it to the yamaha dealer to get them to get it dialed in, it's super easy to change the weights without taking the clutch off, just hold cover when removing those 10 mm bolts on the outside, then use a 2.5 mm allen wrench and loosen the set bolts on each side of the weight, then take the bolt that holds the weight off and remove bushing and they fall out, super easy, took 45 mins.

 

[kilometers]

This is kinda self explanatory.

You only Installed rivets in the lower hole. Theirs 2 more holes to fill before you have to mess around with anything else

And If you think about it the weight on the tip should make the biggest difference because it's further out on the arm. Not the hole closest to the screw


Safe yourself the money clutching isn't a one shot deal take it back apart and add another rivet. And repeat test. Most guys do this in the field. Because it usually takes more then one try.

 

[HYFLYR]

You should have blue brown blue spring, 13.3 in the heel and 17.7 gram rivets in the mid and toe with 22/40 gearing at 1-4000ft. White secondary spring at 3-3. You will not over rev with that setup. It will pull much harder with more weight or you can even run a 20/40 just a little more base or heel weight and it will work good too.

 

[russellrox]

You should have blue brown blue spring, 13.3 in the heel and 17.7 gram rivets in the mid and toe with 22/40 gearing at 1-4000ft. White secondary spring at 3-3. You will not over rev with that setup. It will pull much harder with more weight or you can even run a 20/40 just a little more base or heel weight and it will work good too.

I have a green white green spring, that's the stock spring, I will leave the weights that I put in on the heel, plus I got 3 more weights that I am going to add to the tip, I will leave the mid hole without a rivet, will give that a shot and see how it goes.

 

[akvector]

Hyflyer when did the white spring start being used because my 08 does not have a white spring.

I have GWG spring with stock weights and rivets for 1-4 and 20/40 gearing and I under rev

 

[HYFLYR]

The green white green is a good spring too but has more preload and finish rate. It can be used but likes alot of weight like fully loaded, to get a full shift on that spring. I too like the 20/40 gearing for low elevation, although yammi recommends higher gearing for some reason which is dumb, it's a mtn sled not a trail sled. How are your weights loaded and also what is your secondary position set to akvector? They have been usin the white spring in the 162 sleds, works good for most applications.

Russell, try putting some weight in the mid, it will pull more consistent through the rpm range and have more consistent shift points. Also, you won't have any lazy spots or flat spots in the power range plus these motors love weight in the primary!!!

 

[HYFLYR]

The green white green is a good spring too but has more preload and finish rate. It can be used but likes alot of weight like fully loaded, to get a full shift on that spring. I too like the 20/40 gearing for low elevation, although yammi recommends higher gearing for some reason which is dumb, it's a mtn sled not a trail sled.

Russell, try putting some weight in the mid, it will pull more consistent through the rpm range and have more consistent shift points. Also, you won't have any lazy spots or flat spots in the power range plus these motors love weight I. The primary!!!

 

[akvector]

Stock weight set up for the altitude comp i just put the gwg primary spring in as I like it better!! But the secondary has the pink spring pretty sure i am at 6-2 but you know 08s are not marked very well

It does fine most of the time but I have never reached peak rpm even at the ville.