The Canadian National Superbike Championship Series (CSBK) have confirmed the technical rules package for the Amateur Lightweight Sport Bike category, sponsored in 2021 by veteran racer Toni Sharpless’ new Super Sonic Roadracing School.
The specific, updated rules for the 2021 Ltwt National category are available here: https://www.csbk.ca/images/competitors/2021_lwsb_rules.pdf
The Lightweight Sport Bike class was launched in 2018, a development of the previous Kawasaki Ninja 300 spec and Honda 250 Cup Championships. During the past three National road race seasons, Yamaha, Kawasaki, and Honda production-based Ltwt equipment have earned victory in Amateur Lightweight Sport Bike National Championship action.
Rules developments for 2021 are minor. Technically, the guidelines for the earlier-model Kawasaki 250cc and 300cc Ninja models have been loosened, meaning racers can build (improve) the engines for these machines to keep them competitive in the class. Kawasaki Ninja 250 and 300 models have won National rounds over the past three seasons.
Attracting the most attention is an update of the spec tire choice for the series, with an improvement from official supplier Dunlop. After three seasons with the DOT-approved Q3+ tire, the series will move to pure racing slick tires: the front KR448 110/70R17 and rear KR451 140/70R17 rear. All the classes in the CSBK Series now use Dunlop racing slick rubber, with Dunlop starting their eighth consecutive season with CSBK in 2021.
Tire warmers will now be permitted and recommended for the Super Sonic Roadrace School Amateur Lightweight Sport Bike CSBK National category. As previously, grooved rain tires are also an option for inclement conditions for the Ltwt category.
These new Ltwt tires are produced along with the other Dunlop racer tires for bigger race classes in Buffalo, New York. The equivalent MotoAmerica Lightweight category has been using these Dunlop slicks for the past few years.
“We expect to see an improvement in lap times with the switch to these slicks,” explained Sandy Noce of Pro 6 Cycle, the official distributor for Dunlop motorcycle race tires in Canada and at-track service provider for the Canadian National Superbike Championship.
“We have solid data with these tires on all the current Lightweight machinery from use in MotoAmerica as well as here in Canada at the Regional level, and we know they offer more grip than the previous spec choice in Canada, the Q3+. The slick design provides a quicker transition entering turns, and a larger contact patch when the bike is at full lean. The Lightweight slicks are developed from the larger-sized KR448/KR451 currently used in our Superbike and Sport Bike (middleweight) categories.”
The complete, updated 2021 CSBK rulebook will be available on the csbk web site on Monday, April 26.
(From a CSBK press release, April 22, 2021)