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KTM 280 Big bore Kit

Here's what Motocross Action Magazine said about it:

"Big boost: Dollar for dollar the most efficient way to get more power out of a four stroke is to increase the displacement."

The KTM280 Big Bore Kit "...kit is inexpensive and powerful"

KTM 250 Big Bore Kit "...makes it easier to get off the line and more adept at handling hils, sand and mud."

KTM 250 Big Bore Kit "...pulls like a John Deere to the first turn, there is nothing like three more horses focused on one job."

Motocross Action

What does it cost? Would you believe $469.00. That's it and all you have to do is button it up and check your carb jetting.

KTM 250SXF Big Bore Kit

( 280cc Big Bore Kit )

All you have to do is send us your cylinder (can be in almost any condition) and we'll bore it and fit it with a hardened alloy sleeve. We will bore it to 80mm and honed it to fit a JE 12.5:1 piston. The kit comes complete with a JE piston Kit and top end gasket set. Nothing else to buy.

All for only.... $469.00

Also Available is a 13.5:1 compression model ....Only $484.00

KTM 250SXF Big Bore Kit

( 265cc Big Bore Kit )

Your cylinder will be bored and Re-Nikasil coated to fit a 78mm Wiseco Piston. The kit includes the Wiseco piston, rings, pin, clips and top end gasket set.

The standard compression ratio kit is $476.00

The Kit With a Hi-Compression +.5 skirt coated kit is $495.00


We highly recommend using the Crower Power Cam -Victory Series. Developed to give your engine more power in the mid-range area of the powerband. The Victory cam is recommended for use on outdoor style motocross applications. This camshaft works equally well for recreational off-road riders. Everyone from fast novice riders to some of the fastest pro's can benifit from it's design and performance

Call for price

We also recommend the Dr. D Exaust to complete the package. $495.00

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Increase Your Low End and Your Fun At The Same Time

The most economical and effective way to increase the performance of your engine. Available for two stroke and four stroke KTM Motorcycles a like. Whether racing or just trail riding, increasing your engine displacement with a big bore kit will give you that added power you've been searching for. Big bore kits are very reliable and easy to install when compared to most other engine modifications.

Send us your cylinder (and head, along with the power valves/two stroke cylinders only), we will bore, sleeve or Re-Nikasil your cylinder to the new larger size. Your power valves will be modified if needed to function properly with the larger bore size. Some models will have the cylinder head re-chambered for the proper volume and compression ratio. Our big bore kits include a high performance piston with piston rings, piston pin and circlips. New top end gaskets are included for most models

KTM 250 SX 285cc Big Bore Kit


KTM-250SX 1990-1994 285cc Kit $595.00

KTM 250 SXF 280cc Big Bore Kit


KTM 250 SXF 2005 - 2007 280cc Kit 12.5:1 compression ratio $469.00

KTM-250SXF 2005 - 2007 280cc Kit 13.5:1 compression ratio $484.00

KTM 280 SXF 280cc KIT click here for details

2007 KTM 250 EXCF 280cc KIT

KTM Big Bore Kits

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