Snowmobile Drags Racer Info

             
      Casterland
             

All Riders must wear an TekVest and all Sleds must have a tether!! ISR RULES.

IT IMPORTANT THAT YOU PRE-REGISTER PRIOR TO EACH RACE EVENT. Riders may Pre-Register until Sunday night, February 14. Registration will close at 10 AM sharp, so be early, don't show up at 9:45 am and expect to get registered for the race if you have not Pre-registered!!! WE WILL NO LONGER ACCEPT LATE ENTRY. THERE WILL BE NO RACE REGISTRATION AFTER 10:00 AM ON MONDAY MORNING, THE DAY OF THE RACE.

Registration will take place at the Ag Grounds, in the red building.

UCMA is ISR Affiliated and we run ISR rules, including all track specifications.

The Track is located on Hwy 236, i miles south of Stonewall, MB.

UCMA is asking all Drag racers to email us so that we can begin to complie a list of racer email addresses. This will greatly assist us in keeping racers informed!!

 

 

SETTING UP YOUR GRASS DRAG SLED

The following items are recommended for you to bring with you to the races.


1) Spare Belt, the most improtant preferably one that is broken in
2) A variety of jet sizes
3) Clutching tools and parts
40 A rake to remove the loose dirt at the start.
5) A wide variety of tools

 

Jetting the Carb


Due to the milder temperatures you will have to install smaller jets in the carburator. Manufactures have a jetting chart for altitiude and temperature. Do not rely on these charts to be 100% accurate. Always make a few test runs and check the plug color. The plug should be a light brown and the center electrode should have a fine white ring around it.

The Suspension

Having the correct weight transfer is one of the most important parts of a great grass setup. A sled with the correct set up will allow the sled to transfer it’s weight quickly at take off lifting skis 1-2 inches off the ground, holding up for the entire run. When skis are on the ground it creates “drag” slowing the sled.
A crew member and the driver can check weight transfer in a stationary position. The drivers seated on the sled and the crew member lifting on the front bumper. The front of the sled should be easy to lift until the skis are slightly off the ground. A test run should be done to varify.
Weight transfer is set by lowering the front of sled and the back of the rear suspension. The goal is to get the sled as low as possible. Most sleds today have a lot of adjustment on the front shock. You can also install softer springs or short shocks. The best way to lower the front is by using shock spacers. in order to do this the shock will have to be disassembled. The use of straps to the down the front end is cheap but greatly affects suspension.
To lower the rear suspension use the limiter straps and shorten the rear shock. When set correctly the sled should pivot on the center shock and spring. Make certain that the spring is stiff to prevent compression. Do a test run to ensure that ski's are held off the ground.

 

Traction Control


There are picked classes and non-picked. The majority of grass drag racers pick thier sled. The type of studs vary due to the track conditions. Chisel Studs work well due to the big face of the stud, grabbing more dirt for traction. This type of stud will also requier more power to pull it out of the ground.
Remember that studs add weight so only use enough studs to eliminate slipage at take off. ISR rules state that the lenght of stud cannot be more than half an inch longer than tallest lug.

Track Resistance.


Use a number of idler wheels to reduce the resistance. Metals or plastic idler wheels create less resistance than rubber as do thinner idler wheels.
Removing the grease from the bearings on the idler wheels is an inexpensive tip. Remove the seal and use a lubricationg spray to clean out the grease. Re-install seal. Remember to re-grease the idler wheels prior to trail riding. Aligning your track perfectly is very important and keeps your run straight.

 

Bearing


A perfectly tuned and dialed in drive assembly is key to great results and perfomances. There is only one way to accomplis this, testing, trial and error.
The goal is 90mph for 600cc, 95mph for 800cc at the end of 500 foot run. The sled manufactures have the gear ratio information for this. The top gear will need to be reduced, a shorter chain will also be needed

 

Clutching


This can be the most difficult to accomplish. The first step is usually a good clutch kit. The goal is to raise the engagemnet rpm several hundred rpm higher. A stiffer primary spring can accomplish this.

But. due to the increased ground traction there will be more belt slip. Use an emery cloth to lightly scour them between seach run on both the clutches and belt, careful they will be hot. Remove all dirt with clean water, re-install belt and adjust the deflection. Check clutch alignment.