Why not use Yamaha's suggested clutch set-ups

[triplel]

I've been reading through all the clutching info on this forum and have not seen anyone say they've tried what Yamaha suggests.
Are their recomended set-ups to general????

I'm riding a stock 2009 Nytro MTX.

I've been reading through the 2009 FX10MTRY, and the 2010 FX10M53SZ / 62SZ tuning specs in the service manuals.
Their recomendations for 2010 have been updated from 2009 for the 153 track length. For a stock sled, for 6-8500' elevation, for 153" track, the 2010 spec is:
-8FS00 weight with 2.4 gram steel rivet in outer hole
-G-W-G primary spring
-16.5mm rollers
-White secondary spring with 60 degree pre-load
-39 degree cam
-20-40 gearing
They are saying 3400 rpm engagement & 8750 rpm shift.

The only change for the 2010 set-up is the white 2ndary spring(2009 it was pink) and the 60 degree pre-load(2009 was 70).

Has anyone tried the 2010 set-up? What do you think about it? I plan on giving it a try next week-end.

 

[mtdream]

too many variables to answer based upon what you posted...

what kind of riding?
what elevation?
what is your weight?
What mods to the sled?
etc. etc.

clutching is everything for getting it all to the track...

 

[triplel]

Re: too many variables to answer based upon what you posted.

Mountain riding, about a foot of fresh powder, 6-8500' elevation, I weigh 200 lbs, sled is stock.

 

[mtdream]

what mileage on sled?
What are you seeing for RPM's?
What dont you like about what it is doing?
What do you want it to do more of? (harder hitting on bottom, top end...

these are just base lines, not meant to be exhaustive...

Clutching at the end of the day is more about preference than science...

I prefer softer engagement so i dont spin the track, and trench...I also prefer a harder pull in the mid-top range...which means I go after a different profile weight than some others...

I also want more pressure (harder pull) on bottom after engagement, so I choose a smaller roller set up...

and, I prefer to have lighter weights and clutches for efficiency sake...some prefer heavier weights, and higher springs etc.

 

[usafracer]

I went out this last weekend and rode with the Yamaha setup in my sled and it sucked. I am 220 LBS 3 feet of powder 700 miles on sled and the most I could get it to spin was 8300 RPM. 4-6,000 feet.

 

[Rx1M5]

Yamaha builds one tough clutch but they don't have a clue how it works. Their setups are virtually useless.
Rx1M5

 

[dfinn]

I went out this last weekend and rode with the Yamaha setup in my sled and it sucked. I am 220 LBS 3 feet of powder 700 miles on sled and the most I could get it to spin was 8300 RPM. 4-6,000 feet.

I weigh the same, have the same amount of miles on my sled and ride in the same condition except most of my riding is done between 8-10k feet. The max I could hold was right around 8300 as well but on a lot of long pulls it was closer to 8000. What's the fix?

 

[philsummers21]

My fix was a stiffer secondary spring(gave RPMS and better backshift) and lost 2.5grams off the tip of my weights.

 

[mtdream]

OK, for those new to Yamaha and other brands....Here is the secret decoder ring....for the best performance gain per brand...


Yamaha- Weight savings and clutching....
Arctic Cat- Pipes and Y-Pipes....
Polaris- Spare Pistons, and well, aluminum recycler...

 

[DamonJones]

My fix was a stiffer secondary spring(gave RPMS and better backshift) and lost 2.5grams off the tip of my weights.

What spring did you use and did you keep the stock weights and just grind them down?

 

[Summitseeker]

My fix was a stiffer secondary spring(gave RPMS and better backshift) and lost 2.5grams off the tip of my weights.

What spring did you use and did you keep the stock weights and just grind them down?

What worked for me was a Green Actic Cat 0748-025 Spring and mounted in positions 1 and 0. I also bought a Shockwave helix so you can change it on the fly for different snow conditions.
However my sled is not stock as it has the MCX270 kit so my setup may not work the same on your sled.