TPS (Again!)

[Guest WildJackal]

I have been following all the TPS threads and taking notes so I would be prepared when I finally got around to adjusting it myself. All to no avail!

 

From my notes:

 

The TPS voltage should be set to 150mV +/- 15mV with the throttle stop screws backed out and linkage unhooked. Measurement is taken with ignition on but engine not running.

 

With the linkage unhooked and idle screws all the way in, turn on the ignition and screw in the throttle stop screws until the TPS voltage is 500-525mv. Start the bike and balance the throttle bodies, insuring the TPS voltage stays at 500-525mV. The bike will be running rough and the idle too low. Back out the idle screws to get idle to 1100rpm.

 

Now my questions:

 

1) Is this correct?

 

2) Where do I measure the TPS voltages? Someone said the outer two wires on the connector to the TPS. I'm guessing the TPS is the gizmo on the top of the right hand throttle body. How do you make a connection to these wires? It looks difficult to do with the connector plugged. What is the trick to probing the TPS?

 

3) I guessing that I loosen the two screws holding the TPS and turn it to adjust to the proper voltage.

 

Thanks for the help!

[Guest Brian Robson]

Pull back the rubber cover on the clip at the top of the right hand tb, and put two small pins (sewing) into the two outer wires and then connect the multimeter to the pins

[Guest WildJackal]

Thanks for the tip Brian. Simple and effective.

 

I set my TPS. My experience:

 

The TPS is on the right throttle body so all the TPS adjustments are made using that throttle body.

 

1) Disconnect the throttle linkage at the right throttle body to isolate the right throttle body.

2) Back out the right throttle body throttle stop screw so it is not making contact. This is easier to do with the air cleaner boot disconnected and pushed in.

3) The butterfly still won't seat because of the choke. Loosening the cable is not enough, you have to remove the small lever held on with a tiny circlip.

4) Turn on the ignition and measure the TPS voltage with the butterfly seated. The voltage should be 150mV +/- 15mV. Mine was 109mV.

5) Adjust the TPS to get the desired voltage. The star screws are a pain. My voltage ended up at 160mV.

6) Screw in the right throttle body throttle stop screw until you get a TPS voltage of 500-525mV when you turn on the ignition.

 

You are done! Put some nail polish on the throttle stop screw and TPS screws. Don't touch them anymore.

 

Now you just need to get the left throttle body in sync with the right and set the idle correctly.

 

Continued .....

[Guest WildJackal]

Continued .....

 

I reconnected the throttle linkage and went for a ride to warm up the bike. When warm:

 

1) Disconnect the throttle linkage to isolate the throttle bodies.

2) Screw both idle screws all the way in.

3) Connect your Twin Max or other synching tool.

4) Start the bike and sync the throttle bodies using only the left throttle body throttle stop screw.

5) The idle will be too low. At this point screw out the idle screws an equal amount until the idle is correct. Seemed to be a little more than a 1/4 turn for me.

6) Stop the bike and very carefully adjust the throttle linkage and reconnect it so it doesn't move the right butterfly. That is to say, the TPS voltage should still be 500-525mV when you turn the ignition on with the linkage connected.

7) Start the bike and continue to sync the throttle bodies using the white knob at higher rpms.

 

Seems to work fine. Any corrections?