TOUR USED PARTS TECH CONTACT

DEALER INQUIRIES INVITED - CLICK HERE

VISIT OUR RACER'S SUPPORT PROGRAM...
SALES QUESTIONS? CONTACT US AT SALES@BIGBORETHUMPERS.COM

WE CARRY THE FULL LINE OF WISECO, JE and CP PISTONS FOR OFFROAD MOTORCYCLES AND ATVs!
COMPARE OUR PRICES PISTON KIT WISECO BIG BORE THUMPERS
YAMAHA 660 RAPTOR 686CC BIG BORE $209.68 $146.90
SUZUKI RMZ250 249CC HI COMP. $212.37 $148.66
HONDA CRF450R 498CC $229.98 $160.92
ABOVE IS JUST A SAMPLE . CLICK ON YOUR MAKE BELOW...
HONDA KTM KAWASAKI SUZUKI POLARIS YAMAHA

Web cams are recognized as the finest and fastest cams money can buy. Webs for most ATVs and offroad bikes are available as "Hardwelds"
A SAMPLING... LIFT / DURATION DESCRIPTION BIG BORE THUMPERS
HONDA TRX 400EX QUAD .385-.370 / 310 PERFORMANCE PROFILE $150.45
KAWASAKI KX250F .378-.340 / 268-260 INCREASE OVERALL POWER $290.20
YAMAHA YZ450F .356-.356 / 277-282 RACE PROFILE $359.55
ABOVE IS JUST A SAMPLE . CLICK ON ATV OR MOTORCYCLE TO BE TAKEN TO YOUR APPLICATION...
ATV CAMSHAFTS MOTORCYCLE CAMSHAFTS
APE is a leading supplier of high performance and racing valves for motorcycles. APE stainless steel valves are precision manufactured from aircraft quality Inconel based stainless steel. This special material offers excellent resistance to heat and distortion.
Honda XR 400R (1996/1999) - TRX 400EX Quad (1999)
PART NO. TYPE HEAD DIA. O.A. LENGTH DESCRIPTION
98131 Exhaust 29mm 101mm Std size / 5.45 stem
98132 Exhaust 30mm 101mm 1mm O.S. / 5.45 stem
98133 Intake 33mm 102.64mm Std size / 5.47 stem
98134 Intake 34mm 102.64mm 1mm O.S. / 5.47 stem
ABOVE IS JUST A SAMPLE . CLICK ON YOUR MAKE BELOW...
HONDA YAMAHA SUZUKI KAWASAKI
The Dyna FS for quads is one of the hottest new DYNA products. Direct Plug in Performance. As used by winning pro racers worldwide. Now available to you! Available with features that will let you customize your quad, and make it the trickest, fastest, baddest one around.

These high tech, top quality coils are designed for maximum performance. They produce spark voltages in excess of 30,000 volts and spark energies second to none. DYNA Coils are made to replace stock coils. Choose from three configurations and five variations of resistance for different applications. DYNA Coils work with point ignitions, aftermarket electronic ignitions and factory electronic ignitions.

Cam degreeing wheels, top dead center tools, valve guide hones, stud removers and more.

Click here to visit the ENGINE BUILDING TOOLS page.

All our cam chain tensioners are manufactured on site from billet aluminum. If we don't list a tensioner for your bike/quad please contact the tech department at:
tech@bigborethumpers.com
and we'll either see if we have a manual tensioner for your application or make one for you.

Scroll down for a list of manual cam chain tensioners for quads and offroad bikes.

MANUAL CAM CHAIN TENSIONER

HUSQVARNA TE610/SM610

FITS '06 - '08

#HTE610 - $51.65

CLICK HERE FOR TENSIONER INFO

CRF450 ADJUSTABLE CAM SPROCKETS.

2002-2006 CRF450R
2005-2007 CRF450X
2006-2008 TRX450R

#ACSCRF450 - $34.95

Megan Oblonsky

BigBoreThumpers.com rider and Team APE member.

CLick here to read her FAST TIMES column.

Photo: Tony Lamping

FREE BIG BORE THUMPERS DECALS
Drop us an email to receive a free Big Bore Thumpers.com decal.
Send an email to: sales@bigborethumpers.com Title the email "Sticker Request" and include the following information:
1. Your name and mailing address.
2. Year, make and model of your offroad bike/ATV.

HEAVY-DUTY CAM CHAINS

Extra heavy duty cam chains are recommended to help eliminate chain breakage which can result in extensive engine damage. Tsubaki is the only true high performance cam chain available. The Tsubaki engineers have worked with top race mechanics world wide to produce the only cam chains that will stand up to the rigorous demands of high performance race machines. These same chains are equally at home in the stock street bike, affording the owner the added protection of a high performance chain at a price less than stock factory replacement chains.

Honda XR250 1995 82RHM2010x102 $96.95
Honda CRF250 R/X '04-06 92RHM2015x104 104.50
Honda CRF450R '02-06 CRF450X '02-06 92RHM2015x112 112.43
Suz. DRZ400 2000 82RHM2010x128 121.21
Yam 250 2001 92RHM2010x114 109.14
YZF400 '98-02 YZ / WR426F '98-02 92RHM2010x120 113.76



MANUAL CAM CHAIN TENSIONERS

APE manual cam chain tensioners are designed to replace the automatic and hydraulic tensioners on high performance engines. The automatic adjusters can back out when the throttle is closed suddenly at high rpm. This allows the cams to go momentarely out of time, and can result in bent valves and/or serious engine damage. Hydraulic tensioners have a tendency to put too much tension on the chain guide under high rpm/high oil pressure conditions, resulting in premature wear. Both problems can be eliminated with the installation of the APE manual tensioner.

No matter what the engine does, the cam chain tension will remain constant. AnAPE manual cam chain tensioner is a must for any kind of performance riding. APE manual tensioners are CNC machined from billet alloy to exact tolerances for perfect fit. All manual tensioners are priced $51.65

If you do not see your vehicle listed, contact the APE tech department tech@bigborethumpers.com to find out if we have a manual tensioner for you.


CAM CHAIN TENSIONER APPLICATIONS
YAMAHA SUZUKI KAWASAKI HONDA POLARIS PREDATOR HUSQVARNA

PART # YT1000 FITS THESE FOUR-STROKE YAMAHA BIKES

TTR125 '00-04
TTR250 '99-04
YZ250F '01-04
WR250F '01-04
YZ400F '98-99
WR400F '98-00
YZ426 '00-02
WR426 '01-02
YZ450F '03-04

PART # YT1000 FITS THESE FOUR-STROKE QUADS

YFM250 TIMBERWOLF '92-01
YFB250 BEAR TRACKER '99-02
YFZ450 '04

RM250 - #KT900

DRZ400 - #ST1300GX

LTZ400 - #ST1300GX

 

KX250 - #KT900

KLX400 - #ST1300GX

KFX400 - #ST1300GX

KLR600 - #KT1050

CRF450 - #ST1300GX

CRF250 - #ST1300GX

#HT600RR TE610/SM610
'06-'08
#HTE610

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