After a long day of riding dunes, you’re ready to head back to camp for some R and R. But you’re itching for just one more dune, and there’s a good one straight ahead. You give your machine full throttle to clear the massive dune and come down hard on the other side. Everything seems OK, but then you throw it in reverse to head back towards camp.
That was the sound of your transmission cracking, and now there’s oil soaking into the sand. You don’t know what broke, but you know it’s not good.
You pushed your RZR too far. Or maybe you haven’t yet but you’re worried this could happen to you on your next ride. That’s why today we’re looking at one key RZR transmission upgrade that can save you tons of money and your weekend dune trip.
One of the most important parts of your transmission is the pinion shaft and snorkel gear. The pinion shaft uses a snorkel gear (also called a spiral bevel gear) to turn the front output shaft. This turns your prop shaft, which delivers power to your front differential for four-wheel drive.
The problem is that the gear meshing between the pinion and snorkel gears is one of the biggest weak spots in your transmission, and we often see transmission failures in this spot. But what causes those failures and why? Let’s take a close look at this costly break and see what exactly you can do to upgrade your RZR Transmission.
First, let’s take a look at the spiral bevel gear itself. “Spiral bevel gear” sounds like a complex industry term on its face, but it’s quite simple when you break it down. “Spiral” means that the gear teeth are in a spiral pattern instead of being straight. “Bevel” means that it’s slanted instead of straight. The result is a gear in the shape of a cone with teeth spiraling around its center.
Polaris uses spiral bevel gears because they are very strong… when you’re driving forward. When your RZR is moving forward, the shape of the gears pulls them closer together and gives them better meshing for smoother, stronger gear mating and less heat buildup. The problems start when you throw the machine in reverse.
The spiral bevel gears on your RZR are more likely to break when the machine is in reverse. That’s because they tend to pull apart when they run in reverse. There are a complex set of forces involved to make them pull apart that we won’t get into, but when they pull apart even a little bit, the meshing can be bad enough to do damage.
That’s because bad meshing puts extra leverage and stress on the gear teeth. You want the whole tooth of one gear to push on the whole tooth of the other gear. If you have meshing where the tip of one tooth is pushing on the tip of another tooth, it’s going to break.
The transmission case and the pinion bearing retainer ring are designed to stop those gears from pulling apart. But the case and the retainer can flex when hot and allow the gears to come apart for a split second. Unfortunately, that’s all it takes for you to chip a tooth and lose both gears, your case, and the rest of your trip.
Apart from never driving in reverse again, what can you do to make sure the spiral bevel gears on your pinion shaft and front output shaft don’t explode? It’s easy—you just need a few RZR transmission upgrades. Upgrading your gears, your case, and your snorkel bearing retainer ring are surefire ways to make sure your transmission can handle the kind of riding you like to do.
SuperATV has an upgraded RZR transmission case built with more material around your spiral bevel gears to keep them from pulling apart. The transmission case has extra ribbing throughout that makes it stronger and acts as a heat sink to keep it cooler. It’s a straightforward and effective way to reduce failures.
To really make your transmission bulletproof, you’ll want SuperATV’s heavy-duty pinion shaft and snorkel gear kit which includes a heavy-duty pinion bearing retainer ring.
We have gone to great lengths to make sure our snorkel gear kit is a perfect fit, runs smoothly, and is made stronger. There are three things we do to ensure that it’s the best upgrade it can be:
First, we use 9310 steel—which is a high-strength gear alloy—to make our gears. It’s the same gear material used in NASCAR vehicles. There’s nothing better out there, and it’s a major upgrade from OEM.
Next, we ensure excellent meshing between the snorkel and pinion gears. We do this by lapping them as part of our manufacturing process. “Lapping” is when you run the gears together so that the pair is broken in straight from the factory. You don’t get lapped gears from OEM or other aftermarket manufacturers.
After all that, we stick them on our testing machine and see how well they mesh. This process involves slathering the gears in yellow grease, then running them together until a mesh pattern appears. Basically, the more grease gets cleaned off the tooth, the better the mesh. We tested out several configurations during R&D and you can clearly see the difference between a good mesh and a bad mesh.
Investing in your transmission is just that: an investment. Upgrading your Polaris RZR transmission parts now will save you time and money down the road. But when it comes to getting something better, make sure you actually know what makes it good before risking your ride on it. At SuperATV, we don’t guess and we’ve got an unbeatable snorkel gear and pinion shaft kit to prove it.