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Big Bore Kit - 790cc, ProCycle

ProCycle Approved
DR650 '96 - '25
Made in USA WARNING: This product contains chemicals known to the State of California to cause cancer and birth defects or other reproductive harm.

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. 

Built cylinders with 790 sleeves installed are usually in stock, but we must have your original cylinder sent to us 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.  Your local machine shop is the best place to ask for this service.)
  • Steel Base Gasket
  • Steel Head Gasket
  • Cam Sprocket Plate
  • Tensioner Gasket
  • 110.6mm DR790 Piston
  • Instructions with DR790 Stickers
CARB race use only
Sleeve/Cylinder Options
Ships same business day
$749.95