It is my view that having the proper track for your snow conditions is the smartest and most economical method of improving the performance of your sled. Your track transfers your horsepower to the snow. Efficient interaction between the snow and your track is vital.
First of all I'd like to address a couple of myths about tracks. You need a big motor to move a bigger heavier track, wrong. A track is a big conveyor belt. The engine has to overcome the drag of the clutches, bearings in the chain case and bogey wheels. Bending the track around the drivers and idlers also creates drag. If you go from a 155" track to a 174", the distance from the drivers to the rear idlers is increased about 9 inches. System drag doesn't increase, just because there is more distance between the drivers and rear idlers. Granted, accelerating a heavier track from zero to 50 MPH will take a longer time as compared to a lighter one. If it takes 10 seconds to accelerate a 60 pound 155" track to 50 MPH, it will take about 20% longer to accelerate a 72 pound 174" track, an extra 2 seconds. That delay will hardly be noticeable. What will be notable will be the acceleration the bigger track has over the smaller one.
A sled will accelerate as long as the track can push against the snow and the snow stays put. Except in very hard snow conditions there is always some track slippage. For each snow condition there is a point where the snow starts to give and move rearward, forward momentum is lost and the rear end starts to sink. We want to use horsepower to move a sled forward, not push snow backward.
Obviously, it is the track's paddles that push against the snow, the more square inches of paddles, the better. My personal sled has a 174X16X3" track on it. There are 21 rows of paddles on the ground, not counting the track leaving the drivers to the rails. I have 528 sq. inches of paddles to move my sled. Using the same logic, a 163X16X2.25" track has 358 sq. inches. A 155X15X2.25 has fewer than 300.
I have been told that it takes twice as much horsepower to climb a 30 degree slope at 40 MPH as it does on the flat. We all have machines with enough horse power to go at least 40 up a 30 degree slope. The problem is that there are times that the track can't transfer this power to the snow. Once the snow starts to give, you are going to slow down. When you slow down the track starts to dig a trench. If you are trenching, you're rear suspension sinks. You are now climbing a steeper hill. That steeper hill requires more horse power and the trenching increases until either you turn out or are stuck. In every situation, my 174 track has about half the paddle loading of the 155 and I will have to turn out later, if at all.
Tightening the track stops the ratcheting, but a tight track doesn't roll as easily as a loose track. You can check this out on your own sled at home. Put it on a stand and take off the belt so that you can rotate the track. Use a fisherman’s scale to pull the track and see how much force it takes to make it move. Now loosen the track so that you can get your finger between the inside drive lugs of the track and the hyfax. Measure this force. You should notice quite a reduction. Our tests indicate that a sled with 162” track, an eight-inch big wheel kit, and a set of anti-ratchet drivers (combo drivers) pulls at 19-20 pounds. Any resistance above this force is like having your brake partly on all the time. You are likely using three to five horsepower just to overcome that extra drag at forty to fifty miles per hour. It’s only logical that lower resistance in the drive system translates into greater available horsepower and speed. Anti-ratchet drivers help to lower that resistance, delivering increased performance without affecting the reliability of your engine.
A third item you should consider is chain case gearing. Mountain sleds as they come from the factory are geared too high for mountain riding. Perhaps yours is too. There is a simple test to see how efficient your gearing is. Mark the inside sheave of your primary clutch with a Marks-a-lot and go riding. After your of trip, look at the mark. If the mark hasn’t been wiped off, you can gear down and not affect the top speed of your sled as you ride it. We have talked with people who were afraid to gear down, because they felt it might affect their top speed. This is a valid concern,
but if you aren’t wiping all the marks off the clutch, then either you don’t have the horsepower to go as fast as you are geared or the top speed of your sled doesn’t fit your riding style. Lower gears increase drive belt life because the normal operating range is moved out further from the center on the primary clutch. More of the belt is in contact with the clutch and is less prone to slip and reduces belt temperature. You will also gain more throttle control at the lower speeds. Your engagement will be smoother and you will be able to get started in really soft snow without digging a hole.
Our drivers are tough. Check this video out. Sand, dirt, high temps and high speeds. These drivers perform well.