Big Bore Thumpers online catalog... Wiseco, CP, JE HONDA KTM KAWASAKI SUZUKI POLARIS YAMAHA Stainless, titanium HONDA YAMAHA SUZUKI KAWASAKI Web Cams ATV CAMSHAFTS M/C CAMSHAFTS Dyna components IGNITIONS COILS CP Exchange kits PISTONS/CYLINDERS Cutch components CLUTCH HUBS BASKETS PRESSURE PLATES M/C and ATV HONDA YAMAHA SUZUKI KAWASAKI Cam Chain Tensioners Adjustable Cam Sprockets Heavy-duty cam chain Engine Building Tools

CRF250 and CRF450 Ultimate head solution. Stainless valve conversion w/ titanium retainers, heavy-duty springs... Starting at $139.95 Click Manual Cam Chain Tensioners CRF250, CRF450, DRZ, KLX KFX, and more... Click DRZ400 Big bore piston kit and finished blocks for exchange Athena Big Bore Cylinder Kits - New castings, with piston, pin, clips, gaskets... CRF450, CRF250 & TRX450 Quad cylinder head kits CRF450, CRF250, CRF150R manual cam chain tensioners DRZ400 heavy duty cylinder stud and nut kit CRF450 adjustable cam sprockets. DRZ400 big bore piston kit and finished blocks in stock for exchange Big Bore Thumpers offers complete block and piston kits for selected motors. All gaskets included. No case machining necessary. TRX450R, CRF450R, KLX400 and LT-450 Quadracer. "Gold Stripe" Valve Spring Kit. Heavy-duty springs, titanium retainers, spring bases Ack Attack team sets new motorcycle land speed record. Fast Times - Desert Racing Series blog by Team APE rider Megan Oblonsky Team APE - our racer's support program.   How to install an APE manual cam chain tensioner. Machining Services - Boring, honing, deglazing. Valve jobs, etc... Become a Big Bore Thumpers Dealer Become a Big Bore Thumpers sponsored racer: Team APE International shipping Free Big Bore Thumpers decals Contact information NEW CRF450 CYLINDER HEADS Stainless valve conversion. Heavy-duty springs, titanium retainers. Completely assembled, ready to bolt on. In stock - ready for shipping. ATHENA COMPLETE CYLINDER BIG BORE KITS New castings with larger water jackets and thicker cylinder walls. Bored to finish size. With piston, rings gaskets, pin and clips. Ready to bolt on. Special introductory prices - limited time. For sales questions email us sales@bigborethumpers.com To place an order contact the APE order desk at (661) 256-7309