This kit is for 2009-2016 KTM XC-W and EX-C models, with displacements of 400, 450 and 500cc.. as well as the Husaberg FE501 and FS510, plus the Husky FE450 and FE501 up through 2016. There is a “KT5B” kit for the 2017 and newer models. Please see other products for the version that fits bikes that do not come with a factory thermostat.
The KTM, Husaberg and Husky “500s” are popular choices as snow bikes, and even have a factory thermostat with bypass – but still run cold because they have 158°F thermostats that don’t totally close off radiator flow when below rated temperature. They have a large thermostat bleed hole that is fine when used as a dirt bike, but on a snow bike it becomes an issue as you just can’t afford to send that much coolant flow through the radiators. The Thermo-Bob 4 is an aluminum housing with a 176°F (80°C) thermostat inside, has different temperatures available as options, and has a port for a temp sensor with a 1/8 BSPP thread.
The aluminum Thermo-Bob 4 fits in place of the factory plastic thermostat assembly.