Youth Classes

Any manufacturer asking to have a bike homologated for the following year must submit an actual bike and specs to MMSX/Dirt Rider offices no later than December 31st.

It is the promoter's sole discretion to cancel, combine classes or re direct riders in other classes!

NOTE: All Youth Entries must have a parent with them at the Arena’s Rider Check In. They will need to sign appropriate release forms at that time. You MUST bring a copy of the Youth’s Birth Certificate to the Check In!!!

MM10Y – 10" Rear Wheel YOUTH Class
No current AMA Pro racers allowed. You must be a minimum of 13 years of age and under 18 years of age as of race date. You must run a 10” Rear Wheel. All bikes must use Air-cooled, 4-stroke engines with Open Cradle Frames, 12” front wheels (maximum) are allowed. Manual Clutches are allowed. Unlimited Engine Modifications are allowed. Maximum Wheel Base is 45 inches. Practice & qualifying - time TBD

MM12Y- 12" Rear Wheel YOUTH Class
No current AMA Pro racers allowed. You must be a minimum of 13 years of age and under 18 years of age as of race date. You must run a 12” Rear Wheel. All bikes must use Air-cooled, 4-stroke engines with Open Cradle Frames, 14” front wheels (maximum) are allowed. Manual Clutches are allowed. Unlimited Engine Modifications are allowed. Maximum Wheel Base is 49 inches. Practice & qualifying - time TBD

MM12Y Stock/Mod- 12" Rear Wheel YOUTH Class
You must be a minimum of 9 years of age and under 13 years of age as of race date. This Class is for KLX/DRZ110, CRF70, TT-R110/90, Pitster XJR 90 SS and BRAAP 88cc Motorcycles Only.

The following items must remain "Bone Stock": Engine cases, Engine head and cylinder (No AFTERMARKET heads allowed) (No cylinder spacers allowed), carburetor (re-jetting is OK. Choke must remain on carb), carburetor manifold, engine appearance (do not paint or coat cases), frame, swingarm, forks, wheels hubs (wheel size must remain stock), brakes, fuel tank.

Bikes can be modified by changing or adding the following parts: Upper tripleclamps, handlebars, grips, brake cable, throttle cable, kill-switch, throttle assembly, sprockets, graphics, tires, piston, rings, exhaust system, clutch springs and plates (clutch must remain fully automatic), dual action clutch allowed, however clutch lever must be removed, CDI box, air filter, fork springs, rear shock, chain, sprockets, footpegs/mounts, skid plates, rims and spokes, shifter and brake lever, seat covers and foam, plastic (i.e.: fenders, shrouds, number plates can be replaced in color only- must have white backgrounds).

Practice & qualifying - time TBD

Thumper Talk

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    Sat, 04 Feb 2012 07:12:23 +0000

    ooking to swap my front forks, complete front and rear wheels, and speedometer device for the same parts off of a drz400SM. Thanks!

    KX100 supermini

    Sat, 04 Feb 2012 06:52:04 +0000

    ey everyone!!! just wondering if someone can give me help on jetting my kx112 motor built by eric gorr. I will be using a pwk 28 mm carb. running a ...

  • Escaping the snow! Early tomorrow morning (2/4/12)

    Sat, 04 Feb 2012 06:38:59 +0000

    uffice it to say, my friends are spontaneous. We're loading up EARLY in the a.m. to beat the ski traffic and go ride around Grand Junction! I've nev ...

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