More than a decade has passed since the final year of the famous Yamaha Banshee, but we fans of the outrageous twin-cylinder, two-stroke, six-speed, high-performance sport quad haven’t let our enthusiasm for the machine bog a bit. Fortunately, the immensely popular high-performance ATV remained in production for nearly 20 years, and Banshee-loving aftermarket parts suppliers continue to offer countless ways to keep the machines running strong, or much, much stronger than stock if that’s what you desire. We got our hands on a neglected 2004 with a blown engine and got it running better than new on a budget using affordable, easily accessible aftermarket parts from some of the many performance parts sources that love the Banshee as much as we do.
BUILDING A BETTER BANSHEE FROM THE BOTTOM UP
Our project Banshee’s riding days came to a sudden end years ago when it was run hard in the dunes without proper carburetor jetting. When excess combustion heat caused the pistons to fail, debris from the melting pistons took out the crank, completely wasting the engine. Rebuilding a stock crank can be costly, so we ordered a complete long-rod stroker crankshaft assembly from Hot Rods. The crank can boost displacement up to 403cc. Vertex 66mm pistons gave us 397cc. The stroker crank comes fully assembled and trued with new bearings and rods and requires special pistons and a special gasket kit or head machining for proper piston dome-to-cylinder head clearance. Phathead Racing modified our cylinder head domes to accept the special pistons. A Vitos jet kit provided jetting to keep the engine running crisp without worries of lean jetting making it crispy.
While the engine was being rebuilt, we saw the stock reeds were looking rough, so we replaced them with Moto Tassinari V-Force high-performance reed assemblies. A new Uni Filter replaced the aged stock part. FMF, one of the best sources for high-performance exhausts, still sells the famous “Fatty” expansion chambers and Powercore 2 silencers we loved so much back when you could walk into a Yamaha dealer and buy a brand-new Banshee.
UPGRADING THE HANDLING
The Banshee’s basic, non-rebuildable front shocks are adequate for a stock 350 when they’re fresh, but our ’04s were tired. Race Tech’s rebuildable G3-S shocks gave the Banshee state-of-the-art front suspension, and Race Tech fully rebuilt the stock rear shock to give the Yamaha a balanced, better-than-new feel. The Banshee’s tires and wheels had also seen better days, so we replaced the wasted original rolling stock with DWT XC tires on DWT aluminum wheels.
GETTING ON IT
Riding any Banshee is electrifying from the moment you light the thing off with the kickstarter. Firing up a big-bore version tuned for race gas with racing exhausts is a flood of good sensations. The crackle from the pipes and the aroma of race fuel and two-stroke oil let you know the two-stroke twin is ready to get to work.
Stock Banshees are light on low-end power, but our long-stroke, high-compression mill pulls solidly off the bottom. As with all Banshees, when it comes on the pipes, there’s just nothing like it. The 400 makes a stock 350 feel like somebody pulled a plug wire off. Feeling the power hit is so much fun, we backed out of the throttle again and again just to feel its afterburner-like acceleration kick in.
Race Tech’s G3-S shocks and the expertly rebuilt and -valved rear shock eliminated the Banshee kick we didn’t care for. Stock Banshee suspension is harsh. The Race Tech components are plush and responsive and have much better bottoming resistance for big G-outs and jump landings. Our project machine delivers all the excitement we’ve always loved the Banshee for, with better handling and the power dialed to 11. Memories have a way of beating reality, but this Yamaha makes us want to live in the present.