A Yamaha R6 relies on precise throttle openings to operate at its peak potential on the road or the race track. But a sticking throttle can not only cost an R6 rider a race track victory, it can create a very dangerous situation for all involved. A sticking throttle is often caused by an over-tightened or unlubricated throttle cable, which causes the inner steel cable to bind and hold the throttle in a partially opened position. The carburetor or throttle body valves can also stick open if there is a buildup of dirt or debris preventing the throttle from closing.
Things You'll Need
- 4 mm Allen wrench
- 10 mm socket
- Socket wrench
- Phillips screwdriver
- Spray-on carburetor cleaner
- Shop towels
- 10 mm open-end wrench
- 12 mm open-end wrench
- Motorcycle cable-specific lubricant spray
Park the motorcycle on its kickstand and shift the transmission into neutral. Start the engine and let it idle for three minutes. Turn the handlebar completely to the left.
Turn the handlebar to the right and watch the tachometer. If the engine rpm increases while the handlebar is turned to the right, but decreases when turned back to the left, the throttle cables are too tight and must be loosened. Stop the engine if the engine rpm does not change regardless of handlebar position.
Loosen the throttle cable lock nut located below the throttle assembly on the right handlebar, using a 10 mm open-end wrench. Turn the cable adjuster clockwise two to three complete turns to loosen the throttle cable. Turn the handlebar to the right and watch for an increase in engine rpm. Loosen the throttle cable further until the engine rpm returns to a 1,200-rpm idle, then tighten the adjuster lock nut. Skip this step if the engine rpm did not change when the handlebar was moved from side-to-side.
Turn the fuel valve, located under the left side of the fuel tank, to the "Off" position. This step applies only to carbureted YZF-R6 models.
Remove the rider's seat from the motorcycle using a 4 mm Allen wrench. Remove the forward fuel tank mounting bolts, located near the handlebar, using a 4 mm Allen wrench or a 10 mm socket and a socket wrench. Remove the lower fuel tank bolts using a 10 mm socket. Lift the tank off of the motorcycle and unplug the fuel gauge connector. Pull the fuel hose off of the fuel valve or the fuel pump outlet under the fuel tank.
Loosen the clamps attaching the air box to the carburetors or throttle bodies using a Phillips screwdriver. Remove the air box mounting bolts using a 10 mm socket. Lift the air box off the carburetors or throttle bodies.
Inspect the carburetor or throttle body throttle valves for dirt or debris buildup preventing the valves from opening or closing. Close the throttle as much as possible. Soak any obstructions with a spray-on carburetor cleaner, then wipe the debris away with a shop towel.
Loosen the throttle cable lock nuts on the left side of the carburetors or throttle bodies using a 10 mm open-end wrench. Pull the throttle cables out of the throttle valve lever. Move the throttle valve lever into a fully open to a fully closed position by hand. Clean the linkages connecting the individual carburetor or throttle body valves using a spray-on carburetor cleaner if the throttle valve lever is difficult to move or binds at any point.
Remove the throttle housing from the right handlebar using a Phillips screwdriver. Loosen the lock nuts securing the throttle cables to the bottom of the throttle housing using a 12 mm open-end wrench. Pull the cable ends out of the throttle twist grip, then unscrew the throttle cables from the throttle housing. Pull the throttle cables out from the motorcycle's frame.
Pull the throttle cable ends in and out of the throttle cables. Lubricate the cables with a motorcycle cable-specific lubricant spray if you feel resistance at any point while the throttle cables are moving within the outer cable.
Screw the throttle cables into the bottom of the throttle housing, then slip the cable ends into the throttle twist grip. Reinstall the throttle housing onto the right handlebar. Route the throttle cables around the right fork leg and into the motorcycle's frame to the carburetors or throttle bodies. Slip the cable ends into the throttle valve lever, then tighten the throttle cable lock nuts.
Tighten the throttle cable, using the adjuster near the throttle housing until the twist grip can rotate 1/8-inch before pulling the throttle cable. Tighten the cable adjuster lock nut.
Push the air box onto the carburetors or throttle bodies, then tighten the air box clamps. Screw the air box mounting bolts into place. Reconnect the fuel hose to the fuel valve or fuel pump outlet, then plug in the fuel gauge connector. Reinstall the fuel tank onto the motorcycle, followed by the rider's seat.
Tips & Warnings
- Do not ride your R6, if the throttle is sticking. A sticking throttle can provide an unreliable delivery of power that will cause premature wear within the transmission, as well as a loss of control that could result in a crash. This is especially true if the throttle is stuck in a fully opened position.
- Do not use a petroleum-based lubricant on your R6's throttle cables. These lubricants tend to attract dirt and debris, preventing the cables from moving smoothly and increasing the possibility of the cables binding.
- 2000 Yamaha YZF-R6M Service Manual; Yamaha Motor Corporation
- 2006 Yamaha YZF-R6V Service Manual; Yamaha Motor Corporation
- 2008 Yamaha YZF-R6X Service Manual; Yamaha Motor Corporation