Yes and no. The Associated, Losi, Kyosho, Proline, X-5 and Peak/Orion teams have agreed to run spec tires, but you can run whatever you like (according to race host RC Madness).
Click here for the official announcement at the RC Zone.
From the Team Losi site: “In 2005 ROAR announced that it would discontinue the spec tire rule for the Electric Offroad Nationals. In an effort to control costs and insure a level playing field, Team Associated, Team Losi, Kyosho, Proline, X-5 and Peak/Orion have agreed to compete at this event hosted by RC Madness in Enfield, CT with a spec tire and insert. Also, following in the footsteps of the recent IFMAR ruling, tire additives will not be used by the teams at this event.”
“The driving force behind this unprecedented decision is the cost associated with attending an event of this magnitude. Now the average racer can show up to the event with one type of tire and be assured they will compete against the best without a disadvantage in tire tread, compound or insert.”
The mutually agreed upon tires will use the packaged inserts and are:
2wd Front: Open
Rear: Proline 8184-02 (M3 Holeshots)
4wd Front: Losi 7282R (Red Blockheads)
Rear: Losi 7369R (Red X-2000)
Truck Front: Losi 7505R (Red Directionals)
Rear: Proline 8192-01 (M3 Holeshots)