Endurance Challenge races have three classes for motorcycles:
Formula 125 + Scooter
Formula Middleweight
Open Mini
Please see the Endurance Rules for exact class requirements.
Some examples of specific motorcycles for the above-listed classes:
Formula 125 + Scooter: Honda XR100, Yamaha YSR50, Honda XR50, Honda Grom, Kawasaki Z125 Pro, Kymco K-Pipe 125, SSR Razkull 125, Yamaha YSR80, Benelli TNT 135, Aprilia RS50 (stock), Yamaha TTR-125, Honda NSR50, Honda NSF100, Piranha SSR 125, Ohvale 110, Aprilia RS50 (modified), Kayo MR125, Honda CBR125, Kawasaki Z125, Vespa smallframe, Vespa largeframe, Lambretta series 1-4, Honda Elite, Yamaha BWS.
Formula Middleweight: Any year YCF F150/155 SM or Kayo MR150, Kawasaki KX65, KTM 65 SX, Honda CRF150F, Chinese YX-engined pitbikes with a 150cc-170cc 2-valve motor (SSR, Pirhana, etc), Ohvale 160, Kawasaki KLX-140, Vespa 100cc 2T scooter, Aprilia RS50 with an overbore
Open: Honda CRF150R, CR/YZ 85 up to 105cc (no powervalve), KTM SX/RM85/post-2019 YZ85 with up to 100cc overbore (powervalve), Kawasaki KX100, Ohvale 190, Pitbikes with Daytona 190 4V motors, 2-valve YX/GPX motors up to 230cc, Honda CRF230, Kawasaki KLX230