LTX 137 lack of transfer..Reasoning/Solution?

[ClutchMaster]

Yea what he said. You can’t possibly expect to have good traction with 96 or even 144 stud pattern with a 200+ horsepower sled, it will just blow the track away. Without studs the only time your likely to hook up with that kind of power is in heavy wet snow.
If your looking for softer springs someone who has access to older snowmobile suspensions should see if they can find a spring that will cross over. Heating and bending the existing springs would help too but not optimal.

 

[ClutchMaster]

Has anyone tried the RTX LE spring?
They are a different part number for the short track.

 

[hibshman25]

There is a trade off with just moving the lower scissor arm forward.....you will loose some of the overall travel in the suspension. Moving just the mount hole in rail front will reduce the distance between bump stop and bottom of torsion spring coils. The suspension range of motion will be consumed sooner and there will be shock stroke not being used. To maintain same amount of suspension travel the lower scissor arm will have to get longer.

I'm still approaching this a different way before I start altering the rails and arm geometry.

 

[cannondale27]

There is a trade off with just moving the lower scissor arm forward.....you will loose some of the overall travel in the suspension. Moving just the mount hole in rail front will reduce the distance between bump stop and bottom of torsion spring coils. The suspension range of motion will be consumed sooner and there will be shock stroke not being used. To maintain same amount of suspension travel the lower scissor arm will have to get longer.

I'm still approaching this a different way before I start altering the rails and arm geometry.

Everything is a compromise for sure.

 

[jonlafon1]

The 137 is not made to transfer much. I made the mistake of trying to get mine to transfer like the 2012 f8 128" and 2015 7000 129"
I understand the desire to make things better. (and love reading about peoples thoughts on how)
..I feel the 137 is better suited to ride flatter and if you fight it and try to make it transfer like a 129 your going to be chasing the ride and set up.. Ask me how i know?? If you want that huge pivot point(A LOT of transfer on and off gas) get the 129. I like to think of the front suspension shock and spring as the pivot(the shock and spring directly under you family jewels)).. And still feel this shock and spring is the MOST important piece of the procross chassis both 129 and 137 for trail riding, good handling, easy steering ride.
Everyone likes to think of transfer being the front skis lifting on take off, BUT do not forget the transfer when you let off the gas into a corner or just let off to slow down. The slight drop of the front end is just as important and has a direct link to the transfer everyone thinks of. The biggest thing that i noticed on a 129 was the ability to drive it hard into a corner and let off the gas right where you wanted to start your turn. the 137 you can not drive into a corner as hard and as far BEFORE letting off. It just feels flatter. I thought of my 129 as more aggressive and faster through tight turns, and liked the harder on off flipper movement. But trail riding 180 miles in a day give me the 137"

 

[ClutchMaster]

The 137 is not made to transfer much. I made the mistake of trying to get mine to transfer like the 2012 f8 128" and 2015 7000 129"
I understand the desire to make things better. (and love reading about peoples thoughts on how)
..I feel the 137 is better suited to ride flatter and if you fight it and try to make it transfer like a 129 your going to be chasing the ride and set up.. Ask me how i know?? If you want that huge pivot point(A LOT of transfer on and off gas) get the 129. I like to think of the front suspension shock and spring as the pivot(the shock and spring directly under you family jewels)).. And still feel this shock and spring is the MOST important piece of the procross chassis both 129 and 137 for trail riding, good handling, easy steering ride.
Everyone likes to think of transfer being the front skis lifting on take off, BUT do not forget the transfer when you let off the gas into a corner or just let off to slow down. The slight drop of the front end is just as important and has a direct link to the transfer everyone thinks of. The biggest thing that i noticed on a 129 was the ability to drive it hard into a corner and let off the gas right where you wanted to start your turn. the 137 you can not drive into a corner as hard and as far BEFORE letting off. It just feels flatter. I thought of my 129 as more aggressive and faster through tight turns, and liked the harder on off flipper movement. But trail riding 180 miles in a day give me the 137"

That’s exactly how I’ve always set up my sleds, procross chassis or not. Once you have the front and rear setup (usually soft) then all I need to adjust for riding conditions is the center spring preload. Short tracks will always handle better on trails that’s why I have a hard time with the growing number of long tracks riding on the trails, blowing all the snow off the corners with their 2” paddles.

But Hey atleast you guys look cool tho!!

137” isn’t too bad but anything longer is a waste on the trail. Heck if they made a 121” I would have bought that! I did a couple 300 mile days last year and my 50 year old girl friend was riding a 2000 SRX with no complaints from her. Toughen up Buttercups.

So a 129” spring won’t work on a 137”?

 

[cannondale27]

That’s exactly how I’ve always set up my sleds, procross chassis or not. Once you have the front and rear setup (usually soft) then all I need to adjust for riding conditions is the center spring preload. Short tracks will always handle better on trails that’s why I have a hard time with the growing number of long tracks riding on the trails, blowing all the snow off the corners with their 2” paddles.

But Hey atleast you guys look cool tho!!

137” isn’t too bad but anything longer is a waste on the trail. Heck if they made a 121” I would have bought that! I did a couple 300 mile days last year and my 50 year old girl friend was riding a 2000 SRX with no complaints from her. Toughen up Buttercups.

So a 129” spring won’t work on a 137”?

They are same.

 

[ClutchMaster]

They are same.

The springs?
Part numbers are different tho

 

[cannondale27]

The springs?
Part numbers are different tho

Yes springs. Same every time I looked.

 

[SumpBuster]

Lots of talk on lack of transfer on 137 vs 129, so I started looking into this myself. I've got 129 and 137 skids and tunnels side by side and started working through them to compare.


The most notable difference is that rear mount of a 137 skid is farther back on the tunnel, so in turn the rear skid arms are farther back on the rails. This changes the distribution of rider weight and I feel could be the reason for lack of transfer.

For an easy analogy think of a single axle trailer. Think of the weight on the skis as tongue weight. Rider is the load on trailer, and the rear skid mounting point is the axle of trailer. The position of rider weight/load is constant between a 129/137 so if you move the rear mounting point/axle farther back like on the 137 there is less weight available on the axle as more of the rider weight is being distributed across the skis/tongue.

With less weight beings distributed across the rear of a 137 skid, to me it makes perfect sense that a 129 transfers better than a 137 when both are sprung with the same rate torsion spring. With less weight available to counter the spring force, I'm thinking that a 137 should come equipped with a lighter spring rate than a 129.

I've been told that there actually is no lighter spring rate available and for me at 210 lbs I can't even get much sit in with the adjuster blocks on the softest setting. I have a friend that just bought an LTX, and at 140lbs the sled is not going squat at all when he gets on the gas! I think I have a solution which utilizes the stock springs....and hope to test it soon. Just wanted to post my thoughts to see what others think.

I didn't think you looked 210!!!LOL!

 

[SumpBuster]

Yes, mine rode better with another person on back also.

So, it's OK to eat more donuts?
Awesome!

 

[**sj**]

That’s exactly how I’ve always set up my sleds, procross chassis or not. Once you have the front and rear setup (usually soft) then all I need to adjust for riding conditions is the center spring preload. Short tracks will always handle better on trails that’s why I have a hard time with the growing number of long tracks riding on the trails, blowing all the snow off the corners with their 2” paddles.

But Hey atleast you guys look cool tho!!

137” isn’t too bad but anything longer is a waste on the trail. Heck if they made a 121” I would have bought that! I did a couple 300 mile days last year and my 50 year old girl friend was riding a 2000 SRX with no complaints from her. Toughen up Buttercups.

So a 129” spring won’t work on a 137”?

per Kevin at Port yamaha both are 18.5 lb. springs with two different part numbers though....probably one for shorter skid vs longer

 

[viper strike]

More than 1 person thinks this will both squat the suspension, improve ride, and create more transfer. I have a Racewerx adjustable block installed and the reason I’m interested in this thread is it doesn’t seem to be much difference to me. Any of the measures related to the scissor stop blocks does not address the geometry where moving the bottom of the scissor mount does. I might try it.

Yes it does it should allow for more uncoupled action in your suspension.

 

[ClutchMaster]

I wonder if they are identical to the Cats? Cat guys say they have a .375” square spring that’s softer than the .410”

 

[actionjack]

Food for thought. Searching through the parts lists, up to 2015 the 129 AND 137 skids used the same 1704-576 and 577 springs.
From 2016 on, the 129 skids still get the 1704-576 and 577 springs, but the 137 skids get the 2704-026 and 027 springs.
I am assuming the 1704s are the lighter springs.

2015 OEM parts list for AC includes SRVipers. Same thing. 129 and 137 got the same spring, then in 16 the 137 got a different spring - 8JP . . . then 8JX . . .

Probably smarter to just try the spring before drilling holes in the rails