Racer X Tested: 2013 KTM 250 SX-F Big Bore

October 3, 2013 9:40am | by:

The Cylinder Works kits have been great for the 250s, however when a new engine comes out the time to get a new model made can take a while. So, for this model we went to Millennium Tech for a bore and re-plate. The stock OEM KTM 250 cylinder has plenty of meat to make it bigger (safely)—so we went over 3mm.

Millennium Tech Strip, bore and re-plate to 81mm   www.mt-llc.com 920-893-5595

Vertex Pistons Big bore 81mm Piston kit www.vertexpistons.com 515-270-2302

Cometic Gasket Top End engine gasket kit   www.cometic.com 800-752-9850

FMF Racing RCT 4.1 Muffler and Ti Megabomb header www.rockymountainatvmc.com 800-336-5437

CV4 Silicone Coolant hoses and High pressure radiator cap  www.rockymountainatvmc.com 800-336-5437

Renthal Rear sprocketR1 Works Chain, Fat Bar’s  www.rockymountainatvmc.com 800-336-5437

VP Racing Fuels U 4.4 – mixed half and half with 91 pump www.vpracingfuels.com 210-635-7744

Uni Filter Two-Stage Air Filter  www.rockymountainatvmc.com 800-336-5437

Dunlop Tire MX51 front 80/100-21 MX 31 rear 110/80-19 www.rockymountainatvmc.com 800-336-5437

DeCal Works Semi-Custom Graphics kit with #’s www.decalmx.com 815-784-4000