4 Stroke Big-Bore and Stroker Engine Kits for Motorcycles

This page includes details of our kits for Honda and Yamaha

HONDA

CRF 450F KITS

CRF 478CC - CRF 450R to 478CC BIG BORE KIT 02-04 (Bore 99mm)
£345 Xtreme piston top end gasket kit

CRF 500CC - CRF 450R to 500CC BIG BORE KIT 02-04 (Bore 101mm)
Kit includes complete Apticote 2000 ceramic cylinder, piston kit and top end gasket set.

Stage two: £595 Xtreme piston top end gasket kit

YAMAHA

YZ 250F KITS

280CC - YZ 250F BIG BORE KIT 2001 - 2004 (Bore 81mm) 13:1 compression
Stage two: £345 with Xtreme piston coatings and gasket kit.

262CC - YZ 250F BIG BORE KIT 2001 - 2004 (Bore 79mm)
£329 with Xtreme piston and top end gasket kit.

YZ 426 KIT

444CC - YZ 426 BIG BORE KIT 2000 - 2004 (Bore 97mm)
£345 with Xtreme piston and top end gasket set.

470CC - YZ 450F BIG BORE KIT 2003 - 2004 (Bore 97mm)
Stage two: £345 with Xtreme piston and gasket set

490CC - YZ 450F BIG BORE KIT 2003 - 2004 (Bore 99mm)
£345 with Xtreme piston and top end gasket kit.