I make the following disclaimer on this story: I am not a veteran snowmobile racer or mechanic. This is a story of my limited experience of half a summer of asphalt bracket racing. I’m sure that there are those of you reading this that have far more experience than I do. I welcome your constructive comments. I’m sure the rest of the people reading this story would welcome your input as well. I wrote this story because I talk to a lot of snowmobilers that have heard about this activity but don’t know how to get involved or where to turn for information on getting involved. For those people I hope this story enlightens them as to just how easy it is to get started in this exciting sport. It’s a shame to leave your snowmobile sit in the garage all summer long when you can be racing and learning.

Take the following Test:

If you answered "yes" to two or more of these questions then you could be a candidate for a fast growing new snowmobile activity: asphalt drag racing. This year (1998) the NHRA added a snowmobile class to the bracket-racing program. That means you can now tear down the ¼ mile asphalt drag strip on your sled. No speed limits. Sound like fun? It sounded like fun to me, the combination of two of my favorite activities: snowmobiling and drag racing. Like some of you reading this, I have no previous experience racing a snowmobile, nor do I have an extensive background in performance tuning a snowmobile. This is all new for me. That’s the beauty of the NHRA bracket racing class. In bracket racing it doesn’t matter if you’re a beginner with a stock sled or an expert with a sled modified to the hilt. You can still be competitive. Bracket racing equalizes the playing field.

The snowmobile asphalt racing at an NHRA track is defined in the NHRA rulebook as "ET Snowmobile class". All snowmobiles run in the same class regardless of modifications. How is that possible you ask? Some definitions are in order here for just what is a drag race and what is "ET" bracket racing. The following is from the NHRA web site http://www.nhraonline.com/basics/index.html :

Consider that you’ll run your sled to get to the staging lane, down the racetrack and back to the pit area. Total running time? 5 minutes, if that. So how hot does it get? Through the hottest days of July with temperatures in mid 90s my sled never cracked 210’F. Typically the water gets up to 160-180’F. The most critical time for temperature concerns is after the race. The water stops circulating when you turn off the engine. Then it heat soaks: the water temperature will go up as it soaks up the heat from the engine. When the engine and water temperatures have stabilized at their peak, then it will start to cool down. So you should have a cool down cart. Generally, the cool cart consists of:

• A cooler or other suitable container to hold 5 gallons of water.
• A pump to circulate the water. A 12v bilge pump works nicely.
• 10 ft of ¾" hose, either garden hose or flexible plastic hose from a hardware store. Be sure to use a hose that is suitable for hot water. Some types of hardware store plastic hose will not stand up to 200’ water.
• Quick connect fittings for the hoses on the cool cart and coolant hose on your sled.
• A 12v battery to power the pump.
• A cart or wagon to put it all in so you can move it around the pits easily.

  

 

 

Connecting the cart to your sled is pretty straightforward. The quickest and easiest way to connect is to tap into the coolant line that goes between the coolers under the tunnel (at least on a Ski-Doo).

 

 

I’m not an expert on clutching. In fact part of the motivation behind racing on the asphalt is that it is an excellent arena for learning about how your clutches and everything else works. Any change you make in your clutching shows up in your ET. I can’t tell you if it’s "hard" on your clutching because nobody had defined for me what they mean by that. What you do have to be aware of is that your belt and clutches will be very hot at the end of your run. Some people (myself included) use a leaf blower to cool the clutches and belt after each pass on the track. I don’t see as many people using the leaf blower at the asphalt races as I do the grass. Probably because you have an hour or more between runs on the asphalt. I had a leaf blower so I use it. If you’re running a stock sled, you probably don’t need to worry about it. You should get into the routine of removing your belt after each pass and performing some basic clutch maintenance. You need to scuff the surface of the belt to de-glaze it. Also clean the clutch sheaves with scotchbrite. You are not trying to remove any metal here, just scuff the faces slightly. Do not polish them or the belt will never grip. When you’re done, clean the clutch sheaves and belt with acetone to remove all particulate and oil residue left from your hands.

As far as what clutch components to use, that’s up to you. If you’re racing your stock sled, you can race with your stock setup. Again, remember that in bracket racing, you don’t have to go fast to win you just have to be consistent.

You can make your stock skis into asphalt legal skis or buy aftermarket skis specifically for asphalt. The majority of sleds I’ve seen have purchased asphalt specific skis. My recommendation is to buy aftermarket skis. In the long run it’ll be a lot less hassle. If you make your stock skis into asphalt skis, then you won’t be able to use them on the snow anymore. Also, with the stock ski conversion most racers use stock idler wheels as the wheels in the skis. My observation on this is that the idler wheels do not stand up to much of a side load before the rubber starts coming off. If one of them blows the rubber you could have a handling problem. By my causal observation at the tracks that I’ve raced at, the most popular skis are the ones made by Whal Bros, followed by the USI skis. Both of these skis use a single wheel in front and rear of the spindle. Here you see sleds with 3 different kinds of skis

 

 

Some tracks mix the snowmobiles with the motorcycle in the same class, some don’t. It varies by track. The track I race at has not combined the bikes and sleds so I have not had that experience just yet.

A typical day at the track starts with tech-in. Some tracks do this each time you race. Some don’t. At the track I race at they tech in the sled the first time you come and put a tech inspection approval sticker on the sled.

Due to the nature of bracket racing, you have to have some time trials to make a determination of what kind of ET your machine is going to run for that particular days conditions. This is one of the attractive things about bracket racing for the novice. If you’re trying some new clutch or engine changes and you sled is slower than it normally is (been there, done that!!) it won’t matter for that day’s competition. What will matter is that it is consistent. My philosophy is that once I’m at the track, I don’t try and go faster, I try and maintain a degree of consistency. Between races I’ll make my changes. Sometimes it’s faster and sometimes it’s not. Keeping in mind that "faster" is not the main objective of bracket racing. Anyway, the day starts with time trials. Usually 3 time trials but if there are interruptions you may only get two. Some tracks run the time trials by class others take the runs in whatever order people line up to run. Using the information gained in the time trials from your ET slip you then decide what your dial-in or index time will be. This is the time that is input into the timing light computer when you stage for eliminations.

When eliminations start, they are run off by the first round of each class. That way the winners of each round have time to return to the pits and do what they have to, to prepare for the next round of eliminations. The losers load up and go home. Plan on having about an hour between rounds. This will vary based on the number of competitors. As the day goes on, time between rounds decreases because you have few vehicles left in competition.

Pay attention to the announcer. Your class will usually be called to the staging lanes when the class ahead of yours starts their eliminations.

Each competitor must have a competition number that is legible and visible from the tower. There is no rhyme or reason on choosing a number. The racetrack does not assign them. My sled is #743, so chosen because that is the serial number of the sled. NHRA recommends displaying it in 4" high block numbers in contrasting color to the vehicle.

 

Reusable stickers

Shoe polish

Dial in display (available from Summit Racing Equipment ~$50)

I use a dial in display. It is much neater and more professional in appearance than the shoe polish. If you do use the shoe polish, WD40 and Castrol Super cleaner degreaser seem to work very good at removing it.

Now that I’ve covered the basics, let me share some of my real experiences with you. I made up my mind from the beginning that I would buy a sled just for racing. I usually turn my trail sled over every year for a new one so I didn’t want to race that one. I chose to start racing with a 1997 Ski-Doo Mach1. This choice was based on:

• I work for Bombardier Transportation Group, in their Auburn, NY facility so I’m somewhat brand biased. There was never any question that I would race a Ski-Doo.
• I choose a triple because it gives me the best upgrade path for when I decide that stock isn’t fast enough to suit me anymore. I can have the 700 warmed up or go all the way to a 1000cc engine. If I had a twin chassis, going to a triple would be a harder task. Not impossible, just harder.
• I always thought the F2000 body style looked "cool". How is that for a good reason? The only difference between a drag race and a car show (or sled show in this case) is the speed of the vehicles on display. So I wanted a sled that looked good to.

The sled I bought had some serious miles on it. So the first order of business was to trailer the sled to Chris Heaven, owner of Powerhouse Racing in Belleville Ontario. Chris made a couple of baseline runs on a Land & Sea dyno to see what the stock performance level was. The engine pulled 133hp@ 8400. I left the engine with Chris and took the rest of the sled home with me. Chris was going to give the jugs a little clean up. I wanted to start racing with a fairly solid engine, similar to his trail performance package. The parameters I wanted to stay within here were to retain the stock pipes and carbs, no work on the bottom end of the engine. A fairly conservative setup. I wanted to get on the track and start practicing my skills, not have to worry about tuning a hyper engine. When my skills are up to par (consistent ETs, good reaction times), then I’ll worry about having more power to go faster.

While the engine was being freshened up I decided to strip the sled to clean and inspect everything. Since I didn’t know the previous owner, I didn’t know the history of this machine. There was no telling what the real mileage was on it. Some things on it I did not want to take a chance on coming apart at 100+mph on the asphalt. The pavement is not very forgiving when you land on it.

I disassembled the rear suspension down to the slide rails, cleaned and inspected them. Found some elongated mounting holes and minor cracks in the rails. I had them welded and re-drilled back to spec. At this point I installed some additional idler wheels in areas where the track was unsupported for more than 6-8 inches. I used Kimpex idler wheels.

 

 

The front suspension got a cleaning, inspection and reassembly. Nothing to do there but make limiter straps for the front springs. These will control how much the nose of the sled will lift before lifting the skis. The front of the sled needs to be lowered as well as the back. You can either use shorter springs or tie down the front end with the existing springs. I used old limiter straps cut to a length that would hold the front down. I attached the limiter straps to the upper and lower shock mount bolts.

Under the cowl the only change I made at this time was to remove the oil injection system. I run pre-mixed fuel in my sled.

When I installed the skid frame I went through the chassis alignment procedure outlined in the Ski-Doo racing manual. Tech tip: First thing you should get is the factory racing manual for whatever type of sled you’re going to race. There are volumes of info in those manuals about tuning everything on your sled. I went through the jackshaft/driveshaft alignment procedure. The best thing about doing this alignment is that at worst you have to buy a few shims, at best you can gain fractions of a second here with proper alignment. Poor alignment between driveshaft/jackshaft and slide rails can scrub of a lot of power.

The most important performance tuning tool that I installed was a RacePak Avenger III. With this unit I could monitor all 3 EGTs, water temperature, engine RPM and jackshaft RPM. From those 2 RPM sensors, the Avenger calculates and displays the clutch ratio in real time. This will tell you exactly what your clutches are doing. You can record those events for up to 25 seconds. This is invaluable for tuning because after a pass down the track you can replay this recording and see your EGT, RPM , clutch ratio and mph as it happened during the race. If you’re racing a stock machine and just working on your consistency, you don’t need this. You can check your plugs and piston wash visually, jet a little fat to be on the safe side. You’re not after ultimate speed in bracket racing. No sense risking a lean burn down.

A few weeks later I went back to Belleville to pick up my engine. It was complete except for some reed spacers. Lacking the spacers I decided to skip doing a dyno run. I would do that when the spacers were installed. I was too anxious to get on the track and start racing. It was already late July and half way through the season.

That weekend there was a race a Shannoville Motorsports Park, http://www.reach.net/~smprace/shannon.htm located 15 minutes east of Belleville, Ontario where Powerhouse Racing in located. This would be a shakedown run. Everything on the sled was set to stock configuration except for the rear suspension being chained down to 1" of travel. That provided a baseline setup to work from. The sled weighed in at 601 pounds with 5 gallons of gas and full coolant system. With me on the sled the total weight is 865 lbs. Based on tests of previous 700s built by Powerhouse Racing, it was estimated that my engine should be making about 10hp over stock. Now if I did my part correctly, the sled should run mid 11s.

The first run down the track the sled lifted the skis about 1ft, carried them well past the 60ft light, then started drifting toward the edge of the track. I had to back off the throttle to get the skis down which resulted in a poor ET of 12.4x @ 100 mph.

I quickly learned that I didn’t need to hang way off the back of the seat like I would on grass or ice. An adjustment of the limiter strap to pull the front of the skid up a bit and staying in the center of the seat, leaning forward over the handlebars seemed to cure the ski lift problem. I was able to muster a best run of 12.35 @ 101 mph that day.

Under normal circumstances of bracket racing, that ET would be ok if it was fairly consistent.. To me, I had a personal goal to make the sled run to it’s estimated potential of mid 11s at 110mph. My mission was twofold. (1) Week to week improvement in my ET; (2) continuously improving my starting line techniques and consistency on race day. I wanted to use this sled to have fun racing, I also wanted to use it to educate myself on performance tuning a snowmobile. So now the hunt was on to find out how to get it down to mid 11s. Shaving .8 seconds off of a 12 second machine of any kind is a tall task. I would accomplish that through chassis and clutching. Most importantly I wanted to learn it on my own, calling upon Powerhouse Racing only when I got stumped as to what to do with the sled.

I spent the next few weeks before my next race going through the clutches. With who knows how many thousands of miles on them, they were pretty sloppy. I lucked out because this was right at the time that Ski-Doo issued a recall on the primary clutch for this machine so I got a brand new primary. The new primary does not have machined sheaves where the old one did. I don’t know how much of a difference it will make. During the off season I will have the new ones trued up. Up until now I’ve had the stock clutch setup in there. Chris gave me a list of suggested helix, springs and ramps that I would need to start narrowing my setup down to one more suitable for ¼ mile drag racing. The problem here was that at my size (6’1", 265lbs) I was not your average size drag racer. So Chris’s records of all his setups for other race sleds would not hold the immediate answer. This was a new challenge for him as well.

I have to admit that for my very next race, I made several changes all at once. I used new ramps, primary springs, and helix. The new clutch setup netted me a series of 11.9x runs at 103-104 mph. I was pleased with the ET reductions. I was headed in the right direction.

Over the course of the 8 weeks that followed, I made several clutch setup changes, gear changes, some chassis adjustments and played with various track tension settings. These changes I made one at a time. I even ran without the headlight to try and force cold air into the engine. I’ve since covered the headlight opening but am still looking at ways to put some cool air from outside the cowl into carbs. I was constantly reviewing the clutching data collected by the Avenger, .as well as the EGT data to help me understand what was transpiring. For a novice sled tuner such as myself, the Avenger data would either support or contradict what the seat of my pants told me about each run. Knowing what the real numbers were after each run, helps me train my "seat dyno" on how to interpret what it senses during each run.

Here is another important tip: if you are going to start tinkering with your sled, keep detailed notes on what you do, what parts you use, jets, needles, springs, ramps, weights, air temperature, humidity, etc. Your factory racing manual probably has a blank race log that you can use or make one up on your own. This information will be valuable. Especially when the changes you make cause you to go slower. You will want to know how to get back to where you were. Do not make a bunch of changes at once. If you do, you won’t know what the effect of each change was.

I’ve accumulated quite a substantial number of clutch parts. Chris was able to point me in the right direction. I never went backwards with any of the tips he gave me. Some of the things I experimented with on my own took me a step or two backwards. That’s how you learn. This is where bracket racing is a little more forgiving than the heads up racing. Some of the setups I tried were slower than previous setups. However, on that given day, the sled would run a consistent ET. Therefore I could still be competitive with it.

I’ve gone through my chassis setup. I’ve changed all the oem bearings in the skidframe to NTN low friction bearings. I’ve deburred, balanced and polished all moving parts in the clutch. I’ve machined the hub in the helix so the secondary spring doesn’t bind on it. I’ve done the same with the retainer cup on the primary spring. You would be surprised all the little pieces and parts that can bind up in your clutching.

I finally got my reed spacers installed and made another dyno run. The engine pulled 144 hp at 8400. A solid 11 hp increase of stock. We also tried a couple of aftermarket mufflers. I was being urged to put a set of pipes on the engine to wake it up. Pipes were not budgeted for so that was out of the question for this year. We did find one after market muffler that allowed the engine to pull right up to 8750 rpm where it registered 156hp. I bought the muffler on the spot. It was a used one so the price was right. There is no name on it so I can’t tell you what kind it is.

During the course of the weeks that I raced this season from July through October, I was able to continuously reduce my ET from 12.4 down to my best time (Oct 4th) of 11.60 @ 110mph. Mission accomplished, mid 11s at 110 mph. I’m sure it will go faster with more tweaking. Then engine is certainly up to the task. Somewhere in the high mileage chassis I’m scrubbing off the power. Maybe my 6’1" body is blocking too much wind? Who knows. Just for a test recently I let another person (Terry Holt, snowmobile class champion at ESTA Safety Park) take a run on my sled. Terry weighs in 100 pounds less than I do. At the end of elimination rounds he took my sled for a time trail run. He ran .35 seconds quicker than I did. Just goes to show what a 100lb reduction is worth. Something you have to straighten out for yourself is when one side of your brain tells you that it’s bracket racing, you don’t’ need to spend the time or money to go faster. The other side of your brain just keeps shouting: FASTER, FASTER, FASTER!!! If you’re not careful, thinking of ways shave another .001 second of your ET will take over your every waking moment. There are two things that make a bracket racing winner: A consistently good reaction time, and a sled that will run on it’s dial in. You don’t have to have a big dollar modified engine to win in bracket racing. In fact that is probably the last place to spend your money. Spend it on clutching and chassis That is what will get you consistent. Then when (not if) you’re bitten by the bug to go faster you’ll be prepared to tune the sled for more power. At some point in time, you will get bitten by the bug to go faster. Don’t say I didn’t warn you.

For now, I’ll settle for 11.60s @ 100. The leaves are changing color and snow is not to far away. Time to put the asphalt sled away and start prepping the winter sled.

This process has been a fantastic learning tool for me. I entered this project at a novice level of snowmobile wrenching. This summer has been a condensed course in clutch tuning, engine tuning, racing techniques, and all around sled mechanics. I don’t think you can race on grass or snow and make such small changes and see the results of the change. On grass/snow/ice there is a much broader range of track conditions that play havoc with your setup and your ability to repeat your ET. Asphalt, while not exactly the same each week, is much more consistent than any other track surface. The ¼ mile doesn’t lie when you make a change, you know if you went the right way or the wrong way.

I have just touched the tip of the iceberg of asphalt racing technology. It would take me a life time of time trials to learn what the stars of the NSSR know about the sport. That’s why bracket racing is such a good way to get started. Big budgets do not guarantee a win light. You can be competitive at whatever level of budget you want. My prime objectives were and still remain:

Have fun
Don’t’ get hurt
Learn about my snowmobile

So far I’ve been having a ball, I haven’t broken anything or had an accident and I’ve learned a heck of a lot. I almost hate to see summer come to an end.

Shopping list to get you started on the Asphalt: These are the minimum items that I recommend to anyone wanting to get into the asphalt racing.

Asphalt track. (Need to have) Currently Camoplast is the only approved track mfg. They have 2 models, hard (60 durometer) and soft (40 durometer) rubber. List price for the tracks are about $450. These tracks have no windows. They are solid rubber tracks, just like a big slick. These tracks are directional. They have arrows molded into the side of the track showing the direction of rotation. Please install the track in the proper direction otherwise it may de-laminate during use.

Wheels on your skis. (Need to have) If you’re handy with tools and can do simple fabrication you can make mounts and install idler wheels on your skis. If you have the budget you can purchase skis from any number of after market manufacturers. I use a pair of skis made by Whal Bros. Racing. List price $325. USI, Hot To Go Racing and other make asphalt specific skis, all are $350 and up.

Additional idler wheels: (need to have) installed in your skid to support the track. You must remove your hyfax. Costs all depend on your type of sled and how many wheels you want to add. The more you can add between the rails the better. Figure on $300- $500 for suspension parts.

If you run a modified engine you will need a clutch guard that covers the clutches.

 

 

The one I have was made from .125" aluminum. You’ll have to fabricate one. The only place that I’ve seen any pre-made are in the D&D catalog for certain Arctic Cat models. Figure $50-$75 if you have to pay someone to make one.

 

Cool cart: (need to have) to cool your engine after each pass down the track. This is commonly accomplished by using a large cooler, a bilge pump, a motorcycle battery, ¾" garden hose, and some garden hose quick connects. Figure on $100 - $150 worth of parts to make this up. Note that you can only run water in your cooling system. Use of Antifreeze is prohibited.

RacePak Avenager III (nice to have) data collection system with engine RPM, jackshaft RPM, EGT bullet probes, Water temperature sensor, remote record/display button. Budget $800-$900 depending on what options you get with this. http://www.exhaustgas.com/

A dyno run (nice to have) on your engine to find the peak hp RPM. This will be valuable when it comes time to tune your clutches. Estimated cost: $100-$300 depends on where you go and how extensive your testing is.

Snell 90 helmet, leather jacket, leather gloves, leather boots. (these are all required by NHRA) Note: if your sled runs faster than 120 mph or quicker than 9.90 seconds, you’ll need a full leather suit like the motorcycle drag racers wear. Estimated costs: $500.

NHRA Membership: $50. I consider this a must have. Membership provides you with additional medical coverage in the event you are injured at an NHRA sanctioned track. You do not have to join NHRA to bracket race.

Tools! You’ll need clutch tools, plus all standard tools to work on your sled. Estimate up to $300 for specialized tools, including a clean out stand to support the rear of the sled.

Repeating costs on race day. Track admission and race entry fee: $30-$40, depends on where you race. Food, drink, $$ depends on how hungry you are.

Consumables; gas, oil, Scotchbrite pads, acetone, rags, spark plugs. You’ll need an inventory of these items at every race.

Creature comforts: a couple of lawn chairs for those long waits between rounds. A portable awning to keep your brain from boiling in the open sun all day long. If you race at a track that has night races and the track does not provide lighting in the pit area you’ll have to have a generator and some portable lighting. $$ based on your local pricing.

Web sites: http://sl.rconcepts.com/ You’ll want to visit this site. It is a web site about bracket racing, maintained by a bracket racer. There is even a practice tree you can hit on all you want at http://www.rconcepts.com/beard/sl/holeshot/index.htm as well as complete guide to the ins and outs of bracket racing at http://sl.rconcepts.com/guide/ET.html.

With these items you can hit the track and start drag racing your sled. Have fun and I hope to see you at the track next year!

I’d like to take this space to thank the people that made this project possible for me:

 

I’d like to give a special thanks to my wife Cyndi for putting up with me during all this. You can just imagine how happy she was when I told here I was going to build a snowmobile for asphalt drag racing and I’d be gone to the race track every Sunday, May through October. I think her exact words were "you mean now you’ll be playing with your snowmobile every weekend all year ‘round?" I gave her a true Tim Taylor answer?. "well, no, not exactly. There usually isn’t any snow in April or November, and besides, it rains a lot in Syracuse, I’m sure some of the races will be rained out". She’s a very understanding woman. Especially since it wasn’t just Sundays. For the first few months of this project I was either in the garage at night, every night, or I was travelling back and forth between Belleville Ontario and home on the weekends.

Chris Heaven, Powerhouse Racing, Belleville Ontario. http://www3.sympatico.ca/teampowerhouse Chris is a dedicated snowmobile performance nut. He snowmobile performance is his life 365 days a year. His business is small, but growing. You get very individual, personalized attention no matter if you just want a clutch setup or a complete trail performance package. Chris has taught me a lot in a short period of time about my sled.

Mike Ingles of Ingles Performance Ski-Doo in Phoenix, NY. http://www.inglesperformance.com Mike has the largest inventory of Ski-Doo parts in New York State. I know, I’ve gotten all my parts through his shop. I think he knows the part number of every part on every Doo ever made. Ski-Doo and Sea-Doo products are their only business. If you're looking for a new or used Ski-Doo or just parts and accessories he’s got it. I’ve bought all my sleds from him and continue to relay on his expertise.

Kim Cole, owner of Ace Precision Tool, Auburn, NY. Ace is a machine shop that has fabricated a number of custom components for my clutches, engine and chassis. Thanks Kim! She completed many Friday afternoon "must have" jobs for me.

Bruce McKee, owner of NDM Precision Welding, Cicero, NY. He has fabricated a number tools and accessories for me as well as shelving and components for my trailer.

Finally to the folks in the fabrication department at Bombardier Transportation in Auburn, NY where I work: thanks for all those little "government" jobs you did for me. Special thanks to Joe Bennett for your contribution.