Best big bore kit for the 300

[OneSlowEXer]

Who makes the best big bore kit for the 300ex?

[400ex men]

Curtis Sparks Racing Over the years, Curtis has developed and built some of the fastest, most reliable four-stroke engines available. The 250X has seen many different configurations. Here is quick list of some of the parts that we offer for the 250X. If you don't see it listed, just contact us.

Pistons

.040 -.080 75- 76mm piston kit $120
82mm piston kit - requires big bore sleeve $179

Camshafts

We have a selection of cams based on your specific application $169
Hard faced rocker arms $140 w/exchange
Heavy duty valve spring kits w/ titanium retainers $115
Crankshaft

Heavy duty connecting rod kit $95
Clutch

Clutch kits
Heavy duty clutch springs $15
Ignition

250X - Sparks Racing offers an aftermarket CDI that raises the rev limit to over 10,000 rpm and sells for $115
300EX - Sparks Racing offers a modification to eliminate your rev limiter for $75

www.sparksracing.com

[cds]

FWIW,

Dunno about the best, but there was a story in the July 2004 issue of 4-Wheel ATV Action Magazine on a 330cc kit by Four Stroke Tech 814-842-6159.

According to the article, Four Stroke Tech's 330ex with a White Bros. E-Series pipe will run with a stock Z400 in a drag race.

cd