How to Increase the Horsepower of a 350 Yamaha
- 1). Unbolt the exhaust canister located under the driver seat of the Raptor. The bolt to remove the exhaust canister is located on the leading side of the exhaust canister and is accessible from the rear of the ATV without removing other parts. Remove the bolt using the socket set, then simply pull the exhaust canister off of the exhaust tubing.
- 2). Install the replacement slip-on exhaust canister onto the exhaust tubing where the stock exhaust canister was removed and tighten the bolt which secures it in place.
- 3). Remove the decorative side cover from the left hand driver's side of the Raptor by first removing the retainer clip which holds it in place. The main retainer clip is a round black fitting located below and to the side of the gas cap. Twist this fitting with your fingers in a counterclockwise rotation to release the body panel.
- 4). Use a screwdriver to remove the compression band which secures the air filter to the carburetor. The carburetor is located directly behind the engine, and the air filter is behind it. With the compression band loosened, the air filter simply pulls away from the carburetor housing.
- 5). Install the replacement air filter onto the carburetor housing. The replacement air filter mounts in the same fashion that the stock air filter mounted, utilizing its own compression band however. Tighten the compression band with a screwdriver to secure the air filter into place, then replace the ATV side cover.
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