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DR350 '90 - '99 DR350S '90 - '99 DR350SE '90 - '99

Includes forged JE 89mm piston 10.5:1 piston, Rings, Clips, Pin, big bore sleeve and top end gasket set. You will have to have the big bore sleeve installed in your cylinder and bored to fit the larger piston.

Ships same business day
$399.95
DRZ400 '00 - '25 DRZ400S '00 - '25 DRZ400E '00 - '25 DRZ400SM '05 - '25
  • Includes aluminum cylinder, piston kit, and special gasket set designed for larger water jackets
  • Bolts on with no machining required
  • 94mm big bore piston
  • Aluminum cylinder designed with wider water jackets for better cooling.
  • Forged hi-compression pistonĀ  12.8:1
  • Includes all necessary Rings, Clips, and Gaskets.
Ships in 3-5 business days
$789.95
KLX140(R) '08 - '25 KLX140L(RL) '08 - '25 KLX140G(RF) '17 - '25

High quality bore kit that shows substantial power gains throughout the RPM range. 63mm piston. 10.5:1 compression ratio allows use of premium pump gas. Complete kit includes: cylinder, piston, ring set, pin, clips and gaskets.

  • Brand new high quality BBR aluminum cylinder
  • 10.5:1 compression ratio
  • 63mm piston
  • Includes cylinder, piston, pin, rings, and gaskets
Please contact us for availability information
$269.95
DR650 '96 - '25

The 790cc Big Bore Kit includes a custom made, forged 9.5:1 piston with rings, wrist pin and circlips. A custom made multi-layer steel head gasket, OEM metal base gasket, tensioner gasket, and cam bolt lock plate and a ProCycle specific big bore cylinder sleeve. We recommend adding a KRAMM-Lox tool for easier piston circlip instalation.

Cylinders with 790 sleeves installed are usually in stock, but we must have your original cylinder as a 'core'. These cores allow us to keep up this program and it is nothing more than an exchange - we give you ours, you give us yours.

This Kit Includes:

  • DR790 Big Bore SLEEVE ONLY (requires your cylinder to be bored and sleeve pressed in)
  • Steel Base Gasket
  • Steel Head Gasket
  • Cam Sprocket Plate
  • Tensioner Gasket
  • 110.6mm DR790 Piston
  • Instructions with DR790 Stickers
Sleeve/Cylinder Options
Ships same business day
$749.95
SV650 '99 - '08

2mm oversize from stock.

Requires cylinder boring only. Bore Diameter: 83mm, Piston Diameter: 82.95 mm

12.5:1 compression. Includes pistons, rings, pins, clips and head gaskets.

Please contact us for availability information
$449.95
KLX110 '02 - '25 DRZ110 '03 - '05

An easy big bore kit that increases your KLX110cc motor to 130cc. Includes piston, rings, pin, clips, and gaskets. A quick and inexpensive way to really improve your engine.

  • 57mm aluminum piston with pin, clips, and rings
  • Includes base, head, and side cover gaskets
  • Requires boring of your stock cylinder
Ships in 3-5 business days
$139.95
WR250R '08 - '18 WR250X '08 - '11
  • Aluminum cylinder designed with wider water jackets for better cooling
  • Forged hi-compression piston
  • Includes all necessary Rings, Clips, and Gaskets

You will need to tune your EFI with something like the Power Commander V to get the most out of your Big Bore kit.

Add EFI Programmer, Dynojet Power Commander 6
Ships in 3-5 business days
$999.95
KLX110 '02 - '25 DRZ110 '03 - '05

If you want a fire breathing KLX110, the BBR 160cc kit is the right choice. This kit allows the largest possible displacement available without the headaches of running a stroked crankshaft.

  • Aluminum Cylinder w/ oversized sleeve
  • Requires boring of your stock engine cases for the larger sleeve
Please contact us for availability information
$199.95
DR650 '90 - '95

Wiseco 96mm piston with rings, wrist pin, circlips, head gasket, and base gasket. Requires your cylinder to be bored to fit the larger piston.

Ships in 1-2 weeks
$268.95
DR350 '90 - '99 DR350S '90 - '99 DR350SE '90 - '99

Includes forged Wiseco 83mm Piston, Rings, Clips, Pin and top end gasket set.

Ships in 3-5 business days
$229.95

ProCycle 425cc BIG BORE 88mm KIT With Cam Complete kit with 11:1 Wiseco piston (with rings, pin & clips), HotCams stage 1 performance camshaft and gaskets. No re-sleeving required. You will have to have your cylinder bored to fit the larger piston.

Please contact us for availability information
$429.95

ProCycle 440cc BIG BORE 89mm KIT 2 With Cam Complete kit with 11:1 Wiseco piston (with rings, pin & clips), big bore cylinder sleeve, HotCams stage 3 camshaft and top end gasket set. You will have to have the larger sleeve installed in your cylinder.

Please contact us for availability information
$519.95
CRF150F '06 - '25

High quality bore kit that shows substantial power gains throughout the RPM range. 65mm piston. 9.8:1 compression ratio allows use of premium pump gas. Complete kit includes: cylinder, piston, ring set, pin, clips and gaskets.

  • All new design
  • Brand new high quality BBR aluminum cylinder
  • 9.8:1 compression ratio
  • 65mm piston
  • Includes cylinder, piston, pin, rings, and gaskets
Ships in 3-5 business days
$279.95

Complete kit with custom made cylinder and camshaft.

  • BBR aluminum cylinder with steel liner (bored, honed and ready to use)
  • 58mm piston, pin, clips, and rings
  • Includes head and base gasket
  • New (not reground) high-performance camshaft
Ships same business day
$419.95

This kit provides much of the performance gain of the more expensive 150 (143cc) kits. But gives better reliability due to the thicker wall of the cylinder sleeve.

  • Wiseco 55mm high compression 11:1 piston, rings, wrist pin, and clips
  • HotCams stage 1 performance camshaft
  • Includes top end gasket set
  • Requires cylinder to be bored to fit the larger piston
Ships in 3-5 business days
$320.95
DRZ400 '00 - '03 DRZ400S '00 - '25 DRZ400SM '05 - '25 DRZ400E '00 - '07

All in one package.

  • Hot Rods complete +4mm stroker crank assembly
  • 94mm big bore cylinder and piston kit
  • Complete gasket set with seals
  • Includes new crank bearings

We suggest adding a set of HotCams camshafts and a new clutch kit for the best results.

Ships in 3-5 business days
$1,099.00
XT250 '13 - '25

For riders looking for advanced performance. Kit comes with everything you need to turn your XT250 into a rocket.

  • 81mm piston kit
  • 11:1 compression
  • Big bore sleeve
  • Top end gasket kit

Ā Ā As with any engine or exhaust modification, you will need to re-tune your fuel delivery system for optimum performance.

Ships in 3-5 business days
$399.95
CRF150F '03 - '05

Big bore kit for the 2003-2005 CRF150F. A simple bore in bore kit that includes BBR's high performance camshaft and valve springs for added performance. This cam features higher lift and duration than stock. Complete kit includes piston, rings, pin, clips, BBR MX cam, valve springs and gaskets. This is the quickest way to add the most power to your bike. Great when combined with our exhaust system, Rev-Box, and Free-Flow airfilter. Requires machining of stock cylinder for installation.

  • Adds up to 3.5 HP
  • 67mm piston, pin, clips, and rings
  • 10.75:1 compression ratio
  • Includes head and base gaskets
  • Makes more aggressive style of power
  • Bike still starts easily and idles smooth
  • Same camshaft as used by the BBR Race Team
  • Requires professional boring of your stock cylinder
Ships in 3-5 business days
$299.95

285cc big bore kit includes Wiseco piston (with rings, pin & clips), HotCams stage 1 camshaft and complete top end gasket set. This is a great combination and a big 'bang for the buck' performance increase. No re-sleeving required. You will have to have your cylinder bored to fit the larger piston.

Please contact us for availability information
$439.95
CRF230F '03 - '25

CRF230F 240cc Kit:

  • 67mm piston, pin, clips, and rings
  • New (not reground) high-performance camshaft
  • Includes heavy-duty valve springs
  • Includes head and base gaskets
  • Requires boring of your stock cylinder to fit the new piston
Please contact us for availability information
$299.95
DRZ400 '00 - '03 DRZ400S '01 - '25 DRZ400SM '05 - '25 DRZ400E '00 - '07
  • Direct bolt-on, ready-to-install cylinder; requires no replating and looks virtually identical to the OEM
  • Nickel Silicon Carbide plated for long life
  • Honed to exact size for easy piston installation
  • Big bore cylinders do not require any machine work
  • Come complete with gaskets, cylinder, 94mm piston, rings, pin and clips
Ships in 3-5 business days
$700.95
  • Includes pistons, ring sets, piston pins, retainer clips and head gasket
  • Wiseco pistons are forged from aerospace aluminum alloys for reliable operation and longevity
  • Hi-Compression pistons fit in the stock bore, providing a horsepower boost without the need for boring your cylinder
  • Big Bore pistons requires boring/replating of the stock cylinder
Choose Bore Size/ Compression
Ships in 3-5 business days
$185.95
XR100 '81 - '25 CRF100 '81 - '25

Complete big bore kit. Bolt it on and ride!

  • Includes a pre-bored, big-finned aluminum cylinder for improved cooling
  • Cylinder, rings, piston pin, & clips
  • BBR exclusive performance camshaft
  • Heavy-duty valve springs
  • Rockers with tappet adjusters
  • Gasket kit
Ships in 3-5 business days
$329.95

Replacement piston kit and gasket set to freshen up your BBR 150 motor. Includes piston, rings, wrist pin, clips, head gasket and base gasket. This piston will not fit in the stock cylinder.

Ships in 3-5 business days
$174.90

ProCycle 440cc BIG BORE 89mm KIT 1 With Cam. Complete kit with 12.5:1 Wiseco piston (with rings, pin & clips), big bore cylinder sleeve, HotCams stage 3 camshaft and top end gasket set. You will have to have the larger sleeve installed in your cylinder.

Please contact us for availability information
$539.95
KLX110 '02 - '09 DRZ110 '03 - '05

New aluminum cylinder with plated aluminum liner. High performance camshaft with lightweight piston. This is the largest bore kit available for the KLX110 that does not require boring your engine cases.

  • Aluminum cylinder with plated aluminum sleeve
  • BBR high-performance camshaft
  • 60mm lightweight aluminum piston
  • Includes gaskets
Choose Year
Ships in 3-5 business days
$359.95

Piston, Rings, Wrist Pin, Wrist Pin Bearings and Circlips included.

  • This is a 2.41mm, oversized piston, so the cylinder will need to be bored.
  • Displacement will go up to 675cc.

NOTE: A top end gasket set is required for installation.

Add Gasket Set, Top End
Ships in 3-5 business days
$268.95

The Complete Top End Performance Kit includes:

  • 102.4mm Wiseco piston 9:1 compression (up from 8.3:1) with rings, wrist pin and circlips
  • Stage 1 camshaft for more power
  • Top end gasket set

This kit boosts your displacement from 644cc to 675cc. Your cylinder must be bored to fit the larger piston.

Please contact us for availability information
$489.95