Making chips, machining the primary & secondary myself

[Kerrdog569]

"If you do the 8DN belt mod you will more than likely have no adjustment left for belt deflection" I have not had this happen on our two Vipers, curious who has had this happen on a healthy 8DN belt?

Me with a brand new 8DN belt and now I have all kinds of adjustment after having Ulmer machine my secondary,certainly not saying everyone will have an issue but I did,I would try it first and see though if your just changing to the 8DN belt you might be fine

 

[Studroes144]

The belt/clutch stuff is a toss up of which way to go on this. There's a few aftermarket viper belts on the market that will work awesome! However if you have the power to really shift out the clutches the stock length belt is more than likely going to bind up the clutches. The 8dn belt is long enough that if you are able to use it you'll have to adjust your secondary just so so that the secondary spring will travel more allowing for less chance of the spring to bind up, however there's a good chance you'll have little to no adjustment meaning you may need to have the clutches machined for it to work. Again this likely won't be an issue on a stock sled going either route. If you're not running your sled in the 105+mph range I doubt as tho you'll really experience the coil binding.

 

[Kerrdog569]

Talked to a guy today who could only get 90mph out of his viper and that seems to be more of the norm with the stock set up,that's why I got it done before I even rode it,don't really ride much at 90+mph but it's nice knowing I can

 

[Studroes144]

Yupp don't blame you a bit there. Mine was a 100mph box stock machine with no clutching done whatsoever, but it sounds as tho that's pretty rare..still seems very strange to me that there's so much variation on sleds that are all setup the same in clutching. There's many more factors other than clutching that affect speed like conditions, suspension, track tension, the sled itself, it's hard to point blame on one specific problem. I do know however that it seems as tho ulmer has done a ton of clutch setting up so that's obviously the best place to start

 

[Kerrdog569]

Couldn't agree more,IMO I think track tension has a lot to do with it,after i studded mine I set the track per specs and I thought it was way too tight so I backed it off a bunch and no ratcheting what so ever,I've always adjusted by feel personally,I know it's not always the best way but I've done a whole lot of trail and all of my race sleds this way and some times ya need to adjust a little more often but once it stretches it's not that big of a deal,loose is fast just not too loose

 

[Studroes144]

Be neat to see how tight some dealers are tightening the tracks during setup, on other yamahas they needed to be real tight. Real tight on the viper=real slow speeds, I tried it. Mine has prolly 1-1 1/2 inches of sag with no pressure

 

[Kerrdog569]

Yeah I would say mine is about the same as yours now and mine had very little sag when I got it from the dealer if any lol

 

[Studroes144]

That causes a lot of drag, certainly a contributing factor to slow speeds

 

[Kerrdog569]

Like riding with the brake on

 

[cannondale27]

The binding secondary spring will cause inconsistancy even stock. Yamaha should not be running that spring. I believe it so close that any number of factors including just snow a inch deeper is enough to bind it up. You all would be surprised at how many people have never held it wide open for miles and never have gotten close to the binding. If you are the guy who does this when given the chance there is options and not all of them require machining.

 

[NOS-PRO]

See I knew you were all over it.

You're the greatest! That goes for all you guys who try to help out others.

I really don't understand those who say " I have the best solution, but I'm not going to tell anyone". We all get better when we help each other out. Isn't that the point of the forum?

Before I get flamed, I'm not talking about vendors. They have products to sell and that's how they make a living.

From my own point of view I will probably end up sending my clutches off next summer to get worked on, but last year I bought a new sled, this year I just put another couple thousand dollars of mods on and I have only so much to spend with 2 kids still in college. So unlike some I have to slow down the process.

So many good points! Well said sxr

 

[NOS-PRO]

Agree with Cannondale - pink spring will bind, white spring will bind also. Last winter i saw 3 springs broken from the coil bind, 1 from a stocker and 2 from a turbo sled.

The pink spring is a good spring, but it needs the clearance to work correctly.

 

[Fast]

In my opinion the only machining needed is if you have a Turbo or big engine mods. Stock clutches with no machining are capable of 105 mph speedo. Not consistently but if they do it once it proves there is no need to machine for anything. The capability is there already just need to have the right tune clutch and power wise to get there. Now if you need to go faster than that maybe machining is needed. Hard to believe though since 98 srx with no machining did 120 mph on radar more than once. Have seen Apex's do that also. Ulmer made a post with the theoretical speeds which seems to be very accurate. You need to ask yourself if you bought a Viper for top end. I surely did not. I would buy a Apex for that. But 100-110mph is enough for sure.[/QUOTE

 

[Fast]

I was looking at the secondary spring in my 19 srx and it looks like its worn on the inside of the coils closer to the center(coil bind), anyone else seeing this?might have to put it on the lathe to eliminate this,question is when taking out .070" do we need to shim more to get the belt height back or does maching change that?

 

[NOS-PRO]

I was looking at the secondary spring in my 19 srx and it looks like its worn on the inside of the coils closer to the center(coil bind), anyone else seeing this?might have to put it on the lathe to eliminate this,question is when taking out .070" do we need to shim more to get the belt height back or does maching change that?

Yes, this is a huge problem for the Yamaha secondary running the Pink, White or Yellow springs for Yamaha.

Thunder Products Clutching have 2 secondary springs that don't coil bind. That is one option.

If you machine your secondary for coil bind, it will not have effect on your belt deflection. That is controlled by the rear of the secondary clutch on the all the Yamaha models except for the Sidewinder and new 2 stroke Yamaha that has Team clutches on it. The Sidewinder belt deflection is controlled at the front of the secondary now.