< G.L.A.S.S. - Great Lakes Antique Snowmobile Series

Modified Class Single Cylinder Ice Enduro Rules 2016


1.1 Must be 18 years old to race mod enduro
1.2 Max 5 Drivers per team (no jumping sleds must ride on team you signed up with)
1.3 Any stock OEM fuel tank is approved
1.4 Starting order will be randomly generated by the scoring program or drawn from a bucket of clothespins by one member of each team unless otherwise noted.


2.1 Built 1980 or earlier (1981 model year built in 1980 not allowed)
2.2 Must have un-altered leaf spring front end 3" ski spreader OK
2.3 No wideing of front ski spindle frames
2.4 You may tilt post but it must remain in stock position at bulkhead
2.5 May alter handlebars and seat for driver comfort
2.6 Any OEM rear suspension allowed. MAX Travel is 6" measured from swingarm to suspension stops
with sled off the ground.
2.7 Must have suspension stops


3.1 400cc or less single cylinder naturally aspirated engine. No limit on overbore, go till she blows!
3.2 Tuned pipe is allowed on All motors
3.3 All exhuast must exit under snowmobile. No side exit of any kind allowed.
3.4 Must have working silencer, will be checked
3.5 Any carb allowed
3.6 Engines must be 1975 or older model OEM snowmobile engine
3.7 No Stroker Cranks
3.8 Must have working original fan cooling system bolted to flywheel
3.9 Ignition-CDI or points


4.1 Metal or Plastic Skis
4.2 5/8" maximum runner height
4.3 6" steering carbide max, 1 runner only must be in center of ski
4.4 Carbide no sharper than 60 degree


4.1 Any stock primary clutch 1980 or older also 94c, Power bloc, 102c and P85 clutch allowed stock
4.2 Any secondary clutch allowed no roller clutches of any kind


5.1 Molded rubber only, any size any year
5.2 No cleats, studs must not protrude past the lowest part of the paddle by more than 3/8"


Race director has final say on all protests, you have 15 minutes to protest a team after the race. You must state your protest to the race director and produce $100 cash. If the protested team was determined legal they will receive the $100, if they were illegal they will be disqualified and you will be refunded your $100

Registration fees

$250.00 to enter.