HJHFJR
Active member
This post is for information of how I solved a high idle speed problem.
While performing a routine TBS I attempted to increase the idle speed but found the idle speed knob very resistant to turning. Finally got it to turn clockwise and the idle speed jumped up to 1300 rpm. Turning the knob counter clockwise did not reduce the idle speed.
The idle speed of the FJR1300 is controlled by a device called a Bypass Air Unit which allows air to bypass the throttle bodies thus raising and lowering the idle speed depending upon the amount of air bypassed. Inside the Bypass AIr Unit is a shuttle valve which when moved allows more air to each throttle body. The shuttle valve is moved by the rotating the threaded end which is connected to the idle speed adjustment cable. When the cable is rotated, the rod goes in and out thus allowing the shuttle valve to bypass more or less air. The shuttle valve is moved back by a spring on the opposite end. In my case the shuttle valve was stuck in its bore and the spring would not move it back to reduce the bypass air, thus reduce the idle speed. On the opposite end of the device is a brass screw which allows access to the spring and brass shuttle valve. I removed the brass screw and spring and used WD40 to lubricate the shuttle valve as best I could. Since the shuttle valve is brass I did not want to damage it, plus there is not part number lised for the device that I could find. Anyway, I used a 1/4 inch wooden dowel and pushed the shuttle valve back down to the other end of its bore and used the idle knob to return it. Doing this several time, I was able to free up the shuttle valve and remove it. I cleaned everything with WD40 and reassembled the Bypass Air Unit. At this time the shuttle valve moved freely in its bore.
Reassembled everything and continued with the TBS. Every thing worked like it was suppose to. Idle speed cold be controled with not further problems.
The only warning is that the parts are very small and if you drop them into the engine compartment you may never find them again.
While performing a routine TBS I attempted to increase the idle speed but found the idle speed knob very resistant to turning. Finally got it to turn clockwise and the idle speed jumped up to 1300 rpm. Turning the knob counter clockwise did not reduce the idle speed.
The idle speed of the FJR1300 is controlled by a device called a Bypass Air Unit which allows air to bypass the throttle bodies thus raising and lowering the idle speed depending upon the amount of air bypassed. Inside the Bypass AIr Unit is a shuttle valve which when moved allows more air to each throttle body. The shuttle valve is moved by the rotating the threaded end which is connected to the idle speed adjustment cable. When the cable is rotated, the rod goes in and out thus allowing the shuttle valve to bypass more or less air. The shuttle valve is moved back by a spring on the opposite end. In my case the shuttle valve was stuck in its bore and the spring would not move it back to reduce the bypass air, thus reduce the idle speed. On the opposite end of the device is a brass screw which allows access to the spring and brass shuttle valve. I removed the brass screw and spring and used WD40 to lubricate the shuttle valve as best I could. Since the shuttle valve is brass I did not want to damage it, plus there is not part number lised for the device that I could find. Anyway, I used a 1/4 inch wooden dowel and pushed the shuttle valve back down to the other end of its bore and used the idle knob to return it. Doing this several time, I was able to free up the shuttle valve and remove it. I cleaned everything with WD40 and reassembled the Bypass Air Unit. At this time the shuttle valve moved freely in its bore.
Reassembled everything and continued with the TBS. Every thing worked like it was suppose to. Idle speed cold be controled with not further problems.
The only warning is that the parts are very small and if you drop them into the engine compartment you may never find them again.
