Now You Can Adjust Belt Clearance on a TRA Primary!
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This is one of those that make you wonder, “Where has this product been hiding for all these years?” The distance between the sheaves of your primary (drive) clutch and the drive belt is very critical for proper CVT transmission performance. The primary (drive) clutch is actually serving multiple functions in that it engages and disengages the drive system, (the true “clutch” function), but it is also acting as ½ of the transmission to vary the shift ratio. The side gap, or belt-to-sheave clearance, is critical to having the entire drive system start out in the proper shift ratio. When a drive belt is brand new and the side clearance is set properly, everything is happy. But as the drive belt wears and narrows, this gap increases and thus the “clutch” has to travel further to grab the belt, and when this happens the system is starting out in a higher gear than it should be. This is especially critical in high-load situations, like deep or w et snow, or when you want the best acceleration.
The new TRA Belt Adjuster Kit from Thunder Products allows you to get your belt to sheave clearance down to .010” to .015” like it should be. Most sleds are not even close to this – in factTRA, snowmobile, clutch, clutching, clutches, snowmobiles,, a side clearance of .080” to .090” is not uncommon. Ask any racer if this clearance is important. All will quickly agree that it is very important for a number of reasons. First of all, it will give you a smooth positive hole shot! This is because the sheaves grab the belt right away and helps to eliminate the belt slippage (that deposits rubber on your sheaves) as well as the heat caused by the slippage. Eliminating heat improves traction on the clutch sheaves and extends belt life.
Speaking of drive belts, every drive belt has a plus or minus factor in size. They are not all the same, especially in width, but also in length. This is pretty much from variances in manufacturing (trying to make them good enough for as little $$ as possible).
The TRA Belt Adjuster allows you to make necessary adjustments to the side clearance without pulling the clutch off. Now that’s nice! Mountain riders will especially appreciate the TRA Belt Adjuster for its ability to deliver a smooth predictable engagement rather than having it “bang in”, causing you to trench out. The smooth engagement will let you get on top of the snow and go!
The TRA Belt Adjuster also gives you a greater top speed potential without changing any gears. Really? Yep. With the correct side clearance, the belt can be pushed higher up in the sheaves, which of course is a higher gear for more top speed.