144" to 151" Extensions or Set-back?

[SnoXer18]

This post is inspired by me just finishing shoveling my MTX out of the yard. Front skis riding nicely on the snow, track dug 3' down to hardpack. Something has to change.

I've had my MTX a few years and never been completely satisfied with deep snow performance. I feel that the MTX is better in deep snow than my REV 440 121" x 1.75" but not by much. The MTX front stays on top of the snow good by the rear is a trenching machine and trying to take off in deep snow often results in massive piles of snow being evacuated out the back and not much forward motion.

That being said. The stock track feels soft, is it just folding over when trying to take off? Is the Maverick junk? I have had a brand new camoplast challenger 151" x 14" x 2.3" sitting in the garage that I purchases about the same time as the sled with plans to replace the track once the stock failed.

#1 is the challenger going to be that much better than the maverick?

#2 which method of making it fit will offer the best all around performance? I still ride trail but mainly use the MTX to boondock through the woods and fields.

I believe that the set-back would offer better performance strictly based on deep snow use, but I question it retaining trail manners. ie. heavy steering and the fact the skid is 3.5" back I'd be putting that much more stress on the center shock. Conversely, I think the extensions would maintain similar trail manners and handling characteristics, but I question weather I'd be giving up a lot of deep snow performance or not.

Basically, is it going to make much difference whether I set-back or extend or is the real game changers going to be the track?

 

[justforfun]

The track is the real difference. I did a 3" setback and 1" drop with rear brackets, amazing difference, rode for a season,and then moved back to stock mounts and put extensions on. I have a season on that and am in no hurry to change back. The setback is a bit less tippy, but I think it turns tighter in the stock holes. Either way, you won't be sorry you put on the 151 for deep snow. If you can build your own rear brackets, do a setback. If not, then buy the extensions and go that route.

 

[Snowmixer]

One additional advantage of the setback over the extensions is that the setback will decrease the angle of attack (where the track first meets the snow) which will help the sled 'get up on the snow' better, as the track is slightly more able to push the machine forward, vs. pushing snow down and digging a trench. If you search back several pages in this Phazer Mountain section, you will find MANY threads going over the advantages/disadvantages of setback vs. extensions, longer tracks, how far to set the skid back, rear bracket templates, etc. It's all there already, just takes a bit of clicking.

 

[canoehead]

What are your limiter straps set at?

 

[SnoXer18]

Set 3rd hole for off trail, 4th for on trail. 3rd hole on trail I feel there is too much steering effort and the front shock bottoms more due to reduced travel.

 

[canoehead]

Have you tried the last hole. Can't remember how many there are. If let it out you will reduce steering effort and also improve the approach angle.

 

[SnoXer18]

I believe running the strap full loose would worsen the approach angle and shortening would improve it.

 

[canoehead]

Look at it this way. When you pull it up it causes you to trench, because the rear of the track is trying to climb up and push your nose down.

 

[SnoXer18]

I rather have the WHOLE track trying to climb onto the top of the snow than just the front foot. Approach angle can be equated to having a bigger tire. Bigger tires have a shallower approach angle and roll down the road easier.

Pulling it up puts the of contact further back along the skid thereby effectively reducing the approach angle. Letting it out and allowing the front to drop out even farther when weight transfers makes it trench worse. Think of it this way, trenching is essentially the track contacting the snow while it is still moving downward and not parallel to the rails. Loose strap, more downward travel. Tight strap, less downward travel.

I also soften my front preload to lower ride height and decrease approach angle a little. Also run the rear stiff so it keeps some weight on the nose.

People have been putting drop brackets on rear suspension mounts forever, this reduces trenching but increases ski pressure. Ski, pressure is not a bad thing, when my front floats and the rear sinks, I think I would want more ski pressure.