Midwest Vintage Racing
F440 CLASS RULES
GENERAL REQUIREMENTS
All sleds must comply with the GENERAL SECTION SLED/EQUIPMENT REQUIREMENTS & REGULATIONS.
Safety
- Riders must be 16 years of age and older to compete.
- Riders must wear DOT approved closed face helmets.
- Riders must wear tech vest / chest protector.
- Riders must wear shin guards.
- A working and safe tether must be mounted to the chassis (not on the bars) and cannot be attached around the arm/wrist.
- Snow flap MUST be touching the ice with rider on the sled.
- Any unsafe sled will not be allowed to race.
1.1997 and older 440cc fan cooled engines only
2. The sled must have original OEM engine, frame, cowl, tunnel, suspension, and variable speed converters supplied by the manufacturer for that model.
3. Only hydraulic welded body, non-revalvable, non-repairable shocks will be used in the front suspension and chassis. If a legal chassis and engine stock production sled originally came with a gas charged, re-valvable shock, the shocks must be replaced with a hydraulic, welded body shock. Shock may not be altered in any way.
ENGINE
1. No component of the engine may be altered, changed, or enlarged from the engine manufacturer’s original Stock specifications, nor may any additional components be added to the engine.
2. Blueprinting will not be allowed. This is also to include polishing, port matching, deburring, glass or sand blasting surfaces or material removal for the purposes of engine balancing or other reasons.
3. Must retain stock stroke.
4. OEM or OEM style replacement pistons are allowed for replacement. Pistons may be up to .020 (.5mm) overbore. Pistons must be OEM or SPI replacements only. No Wiseco pistons allowed.
5. Aftermarket engine gaskets may be used, but original factory spec thickness is required. No changes in engine dimensions can be made by gasket adjustments.
6. Only original type gasket materials are allowed for engine assembly.
7. No engine update or performance kits/options allowed.
8. Oil injection pumps may be removed.
9. Only OEM carburetors are allowed. Must be OEM for the year, make and model.
WINDSHIELD
- Windshields may be removed or shortened, if used, must be mounted in the OEM mounting location.
SEAT/FUEL TANK
- Seat/fuel tank must remain OEM for the model. Seat may be recovered. Seat must maintain the original profile as produced. No alterations to the stock seat except for mounting fasteners and location allowed.
BRAKES
- Brakes may be changed or altered but must remain in the stock location.
FRONT SUSPENSION SPRINGS
1. Any snowmobile suspension spring allowed.
2. Limiter strap allowed but must maintain two inches of travel.
3. Front suspension shocks must be welded body hydraulic shocks.
TORSION BARS / SWAY BARS
1. Must be OEM for the model.
2. OEM diameter and linkage must be maintained.
3. IF IT DID NOT COME WITH IT YOU MAY NOT ADD ONE
TRACK SUSPENSION
1. The complete suspension must be used as furnished and filed by the manufacturer. There will be no suspension options permitted. Travel may be limited with straps or chains but must maintain two inches of usable travel.
2. No gas shocks allowed. Must use hydraulic welded body shocks.
3. Front rail/skid frame shock may be defeated but must be in place.
SUSPENSION WHEELS
1. OEM for the model suspension wheels, marginal snow wheels may be added or removed.
2. OEM for the model rear idler wheels may be added. Aftermarket replacements allowed. OEM style bearings only. No exotic metal or ceramic bearings allowed.
SLIDE LUBRICATORS
- Slide rail lubrication systems allowed. includes lube system or scratchers
TRACK
1. No “R” rated tracks allowed.
2. Any OEM track of original dimensions may be used. Dimensions are defined as track length, width, and drive specified dimension. Example wide X121” Long with 2.52 Drive Pitch. No pitch changes allowed. Track height must be no greater than 1” (one inch) lug height.
** 3. Re-clipping/repair is allowed.
- No hooker studs.
- Studs must not protrude more than 3/8” above the track lug height. THIS WILL BE CHECKED
FRAME and BODY
1. Must have stock hood and belly pan.
2. Headlight may be removed but the hole must be covered if removed. Headlight retention is encouraged as it is a stock-based class.
3. Frame must not be altered, or bracing added. No drilling of holes in chassis with the only exception being if the factory installed reinforcement plates have additional adjustment holes. This is allowed to drill the holes to make adjustments.
4. No chassis or suspension component reinforcement allowed.
CLUTCH
- Primary and secondary clutch must match 1997 or older model year snowmobiles. If OEM does not exist, a new aftermarket replacement is allowed of original dimensions.
5. Numbers must be atleast 6in in height
SKIS
1. Any ski conforming to ISR safety and design rules will be legal to use, in any orientation. Special attention must be paid to ski loop and ski loop attachment.
2. Maximum of 8-inch carbides.
EXHAUST
- Must retain OEM exhaust system. No altering allowed. This includes removal of sound deadening material.
HANDLEBAR
- Handlebars may be replaced, including extensions, to fit the driver. The handlebar column must remain in its original position and centered to the chassis.
CLASS SPECIFIC RULES
1. No use of titanium or carbon fiber components. 2. No use of F500 suspension components in either the front or rear suspensions.
3. No use of F-500 specialized suspension components in either front or rear suspensions. No Hooper/Wahl or other aftermarket F-500 legal kits allowed.
4. Offset of any chassis is limited ½ “ (.500 inch) center to center.
INTENT AND SPIRIT OF THE CLASS. This class is designed to be an affordable, fun, class of competition. It can be a starting point for a young driver or a level of competition for older drivers who no longer wish to compete in hi-level classes. If it is not listed, it does not mean you can alter it. If you desire a class with more liberal rules, or the ability to be creative in construction, please seek another class.