Big HP Needs Big Traction We Called Woody's

Our Viper Grows Bigger Fangs!

Nov. 01, 2005 By Matthew Baynard
Control is a priority number one if your building the ultimate race winner or trail burner. All the horsepower in the world wont help you if you can't control the snomwobile in the twisties. All the horsepower in the world, wont impress your friends if you can't put that hard earned horsepower to the ground either. Traction translates to control, acceleration and deceleration.

That being said, you know that our Vipers will be sporting some serious horsepower under the hood thanks to Bender Racing. The plain old Yokohama track from Yamaha was not going to help the triple piped, trail ported, clutched and jetted machine that Bender build for us put power to the ground. To handle our chest pounding horsepower gains, we turned to Doug Dale and Larry Tiede of International Engineering (Woody's that is) for a traction fix.

Following Woody?s general recommendations on stud quantities based on snowmobile horsepower and riding style we decided on stud length and quantity. Remember that the ski carbides will need to be changed based on the number of studs you install. I decided to go with 192 studs and the 8? carbide runners for the skis since we will be riding Vipers that make more than 160 hp. If we opt for a 835 big bore from Bender, we're looking at 178 hp!

After length and quantity considerations, I selected the 5/16? Gold Digger 60? Traction Master and the new silver 5/16" Mega-Bite in a 1.075" length. The blue Viper will have blue powder coated aluminum square backers and the red Viper will sport the new orange powder coated aluminum square backers. The orange backers are just plain cool and Woody's should have offered them years ago. The powder coating is more durable than traditional painting and will hold up longer under wear. The thicker 5/16? stud shaft adds additional security and durability and coupled with the square aluminum support plates, you should have season after season of dependable traction. You may also want to consider the new 1 3/8" round aluminum backers. The larger diameter has increased the tip over ratings to a range of 18 to 22 pounds of deflection. This is outstanding considering the 1 1/4" square backers are in the 19 to 22 pounds of deflection range. The round backers aren't available in colors yet, so if you want pretty colors you have to stick to the square ones.

I followed the Woody?s formula of adding the stud length (A) plus washer thickens (B) then subtracting the track lug height (C) to calculate penetration. The formula is A + B - C = Penetration. See the stud figure below.

The rule of thumb is to have at least 1/4? penetration but no more than 3/8? penetration for trail riding. If you?re racing, you can do whatever suites your fancy, but even the most aggressive trail riders wouldn?t need more than the 3/8? penetration. For my .92? lug height track the formula was 1.075? + .230? = 1.305? - .92? = .385? penetration. With slight variations in the track thickness you are right on the .38? penetration limit. The 1.075? stud is the limit for trail riders on the .92? lug height track.

Once the studs and lengths have been selected, the fun part starts. Their are a few tools that I would recommend to have on-hand for the installation. Everything can be ordered from Woody's except the torque wrench. I relied on the Craftsman Tool Shop for that.

  1. Woody's 5/16" track drill bit - no other device will do the job, forget about burning holes. (Burning was necessary when tracks had extensive usage of kevlar and not the nylon cords of today. The kevlar would splinter and pull apart if the holes where not burned. Drilling a track does little to reduce the strenght of a modern track however. The heat generated by the spinning drill burns the nylon to keep it from fraying. None of the track manufacturers recommend burning stud holes today.)
  2. The new Woody's indexing tool to align the backers. This has to be the best invention from Woody's yet. It has to be, everyone has already copied the design from Woody's
  3. Woody's track marking pen
  4. Woody's stud template (performance or trail)
  5. A inch pound torque wrench

Before you jump into marking and drilling mode, you need to give your stud pattern a bit of thought. Stud pattern more than any other variable will impact your studs performance the most. Carbide tips do nothing if they are all digging into the same spot. The secret is scratch lines. The idea is to have as many studs as possible all digging into fresh ice or hard pack so they can provide the most traction. Consequently, the more scratch lines, the more traction you'll obtain from your studs. For this reason, we used Woody's performance patterns that have 24 scratch lines over the 12 of the trail templates. If you want to get creative, Woody's can help you get more, but for the trail rider, even the aggressive types, 24 is just perfect. The performance template above gives you an idea of the patterns for 96, 144, and 192 studs. We used the 192 pattern and you can see the placement of the studs provides the optimum number of individual scratch lines.


On the Viper, you can drill the 3/16" rivets out to remove the snow flap to have just enough space the drill and install the studs. To have more room, you can lower the skid frame with the rear lifted. We lifted the rear, but we didn't have to lower the skid frame.
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Using the Woody's performance template, we started laying out the pattern with the white track marking pen. This is the only way to do this. Never place the template and just start drilling. I stud several sleds a year and I always make a mistake laying out the pattern because I'm talking to someone or trying to work to fast.

Trace the entire pattern onto the track. The pattern layout is a two step process. Mark a series of holes then move and mark another series. I put red marks next to the first set of holes and black marks next to the second set. That way I could mark all the reds, move the template and mark all the blacks. It saves time and help reduce the chance of marking an incorrect patter. Once the pattern is laid out, check it carefully. Once you start drilling you can't fill a hole that is drilled incorrectly. With all the white dots, you can do a quick reference to the pattern drawings to see if you've laid out the pattern correctly.

With the pattern checked, you need to check one more very important item. On the Viper, Yamaha installs tunnel protectors at the factory for the bulkhead and tunnel, the tunnel protectors run directly over the track clips. You can't stud under a tunnel protector under any circumstances. Anyone who has, make a BIG mistake. The studs will destroy the protectors very quickly and your tunnel and heat exchangers are next on the menu. This has been an issue on sleds like the 1999 MXZ where the tunnel protectors where just inside the clips and many dealers actually installed studs that hit the protectors. Make sure your studs will not be hitting the tunnel protectors.

Our nicely marked stud pattern is ready to be drilled. After we've checked the pattern, twice.
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Now it's time to drill. Be careful not to drill into the rear axle wheels or any part of the suspension when you start. Remember where your other hand is too, I heard of a guy who made a nice round hole in his hand. One more safety tip, don't forget that the drill bit will be very hot and if you touch it, you'll stick to it.

Aaah, the smell of burning rubber in the morning! After the holes are all drilled, the final and best part is ready to be started. The stud installation. Installation takes longer with the track on the snowmobile, but I don't recommend removing the track to install studs.

The smell of burning rubber fills the garage! The smell of traction in the making filled the air!
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The best way to get this done quickly is to find a methodical approach to doing the installation. I would take it a row at a time. I pushed all the studs in the row through and then installed the backers and lock nuts one at a time. I then tightened all the studs at the same time. Using an adjustable torque cordless DeWalt drill and socket, I was able to tighten all the lock nuts to about 85 in/lbs. Then using the torque wrench, I brought it up to a perfect 100 in/lbs of torque. 100 in/lbs is about the maximum torque for the studs, anything more and you will just strip the aluminum nuts.

With the studs installed and tightened, I used the Woodys' indexing tool to make sure all the backers where aligned. The tool, already copied by others who didn't have the foresight to think of it, replaced the use of channel locks to straighten backer plates. The plates all need to be aligned square to the track to function properly. I've seen installation where they all looked like diamonds on the track. A sure way to destroy the track and studs. The indexing tools helps align them easily and is worth the few dollars extra. It also preserves the powder coated finish on the backers that the channel lock would chew up.

The jobs done, it's time to wait for the snow and riding with the extra control and safety that studs provide. Studded tracks are still controversial, and its still puzzling to me. The riders who enjoy the perfect conditions in Canada don't see the need for them, but I couldn't imagine riding without them in New York or Michigan where a light drizzle can turn a trail to ice. I've been caught too many times on ice covered trails, not to have a studded snowmobile. Local official think they destroy everything they cross, but conscientious riders know to cross roads with care. For me, its a safety issue and the added performance is a great bi-product.

Woody's Testing Track or More Accurately a "Torture Area"

When you buy a traction product from Woody's you automatically assume quality workmanship and durability, but do you know why? We've captured some pictures of the Woody's testing team in action and it help to understand what really goes into the production of a quality stud that will last you thousands of miles on the trail. Before you're ever given the change to buy the studs, its been send to the 'test area' where it most likely didn't survive.

Our project snowmobiles go several thousand of miles with minimal damage to our Woody's studs, but the studs that came off the Artic Kat test sleds looked worse than any stud I have ever seen in my life --- after just a few hundred miles.

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Wide open into a gravel corner with stones up to 3" in diameter pound the skid frame relentlessly.
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A high speed sweeper that cooks the hyfax and destroys the suspension and skid frame with flying rocks.
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A water crossing with an asphalt base is all the relief the track, hyfax, and idler wheels are given.
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When Doug Dale from International Engineering and I discussed the test program for Woody's studs I was amazed about the extensive testing that is done. I shouldn't have been surprised about the testing however, when you consider that an extensive test program has to accompany a product that has well over 75% of the stud market today.


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Holeshots down a 330' stretch of asphalt sometimes result in an flurry of asphalt chunks, studs, idler wheels and suspension parts flying out the back end.
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A picture of the radiator used to keep the Artic Kat test sleds engine in one piece. It wont save the rest of it, but at least the engine survives, sorta.
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Let's look at some of the numbers that are part of the test program, the results of that test program on the product and the results on the test snowmobiles.

  • A 1056' test track that has stone, asphalt, railroad ties and water crossings
  • An annual re-paving to repair what countless holeshots do to asphalt
  • Replacing a hyfax after only 100 miles of testing
  • Frequent stops to replace track clips that are literally ripped from the track
  • Replacing skis several times during a testing cycle
  • Replacing scattered shocks and sometimes complete skid frames every 500 miles or so
  • 5 test laps equals one 1 mile or the equivalent of 50 miles on the trail (Woody's is modest and claims a 25:1 ratio, but I think 50:1 is conservative)
  • Crushing every test mule after the tests since they are no longer usable snowmobiles by anyones standard

Any product is a virtue of its pre-production testing cycles, whether its a new Yamaha Viper that has tens of thousands of development miles on it, a thoroughly tested software product, or a push through stud. Imagine a snowmobile that is so abused, the bulkhead is cracked or the front suspension mounts are riddled with stress fractures, that is what Woody's does to make a stud that is arguably the best on the market. We're biased, and I'll freely admit it, we've only run Woody's stud for a reason, we don't want them to fail.

The next time you pick up a bag of studs at your dealer, you'll look at them a bit differently. It's more than just a chunk of steel with a carbide tip. It's a highly engineered and tested traction device.


6054 N. State Rt. 30
Hope, Michigan 48628
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