Yamaha Motorsports

Big Bore Kits for Yamaha Mini Cycles to Thumpers

Whether your into trail riding, motocross, enduro, hare scrambles, or highway touring, we have the big bore kit you need. How many times have you thought , I wish I had bought a bigger bike? Size Matters! The short route to more power is a bigger engine. This means a larger displacement and the best way to increase displacement is an overbore kit from Kustom Kraft Performance. A Kustom Kraft Big Bore offers the most reliable way to get the power you expect. In most cases it's just bolt it on and tune the carb and you're off to the races (after break-in that is). Another advantage of doing a big bore kit is when your cylinder is fried a big bore kit becomes a no brainer.

Just pop your cylinder off your bike and send it to us along with the printed work order form. You'll find the link to the order form in red above Fill it out completely and put it in the box with your carefully packed cylinder. Don't forget to remove everything from the cylinder that's not needed for modification. Yamaha YFM Blaster 240 cc Big bore Kit

Yamaha Big Bore Kits - 2 Stroke Off Road

Yamaha YZ80

Yamaha YZ80

Yamaha YZ85

Yamaha YZ85

Yamaha YZ125

Yamaha YZ125

Yamaha YZ250

Yamaha YZ250

Yamaha Big Bore Kits - 4 Stroke Off Road

TT-R125 2000-2006 145cc camshaft additional $354.00

YZ 250F 2001-2006 262cc $389.00

YZ 400F 1998-1999 420cc $450.00

WR 400F 1998-2000 420cc $450.00

YZ 426F 2000-2002 444cc $440.00

YZ 450F 2003-2006 470cc $449.00

XT,TT 500 1975-81 534cc $379.00

XT 600 1984-1996 635cc $409.00

XT 600 1984-1996 675cc case boring/not inc $449.00

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Yamaha Big Bore Kits - 2 Stroke ATV

Blaster 1988-2006 240cc $450.00

Banshee 1987-2006 409cc Includes sleeving, piston, rings, pin,head mods and gaskets includes Cool Head $924.00

Banshee 1987-2006 409cc Includes sleeving, piston, rings, pin,head mods and gaskets $725.00

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Yamaha Big Bore Kits - 4 Stroke ATV

Kodiac 400 1993-1999 425cc $359.00

Grizzly 600 1998-2001 675cc *case mods not inc $429.00*

YFZ 450 2004-2006 470cc $449.00

YFM 660R 1998-01 686cc $430.00

Grizzly 600 1998-2001 635cc $410.00

YFM 700 2006-2008 714cc $525.00

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