TPS

TPS : Description
TPS stands for Throttle Position Sensor - a device which makes it possible for the ignition box to know how far open your throttle is, and make ignition timing adjustments, which helps with engine pickup/responsiveness and general all-round rider friendliness.
It's basically a variable resistor, which is mounted on the right-hand side of the carb bank.
Little black thing with two (funny) screws holding it on, and some wires coming out of it.

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TPS: Adjusting tool details
The TPS is held in place by a No. 25 security Torx screw. This is similar to a conventional Torx (star head) screw, but with a metal pin sticking up in the middle of the star, meaning you need a special tool to undo it; the normal run of the mill No.25 Torx drive won't get in there. I'm told they can be found in Halfords, but to date I've never found one.

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TPS: How to Check/Adjust

Checking
With the ignition switched on, disconnect the electrical connector from the TPS, and then reconnect it again
(this switches the tachometer to 'Throttle Position Sensor Adjustment' mode).

If the Tacho displays 5000rpm, the TPS is set correctly; otherwise (in which case it will display either 0 or 10,000rpm), it requires adjustment.

But bear in mind that the TPS is a datum, and should only be set when the carburettors are correctly set up,
so ensure the carb balance/synchronisation (whichever you prefer) has been done, and that the idle speed is
correct, before you start adjusting the TPS.

Adjustment
Using the Security Torx tool, loosen the screws holding the TPS to the carbs;
Rotate the TPS so that the Tacho displays 5000 rpm;
Once the TPS is correctly adjusted (tacho displays 5000 rpm), re-tighten the TPS screws, and then exit diagnostic mode by either starting the engine, or switching off the ignition.

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