Throttle position sensor

Greetings all,

Recently when I was over at my local shop, the mechanic there Brett, asked me if I had ever checked the TPS on my carb, as every TPS he has checked on Husaberg's and KTM's alike were way off.

So, the next time I pulled my carb off I checked the TPS per the owers/repair manual, and lo, the second measurement was way off. This setting is necessary so that the computer knows when the throttle is closed, IE at idle, and thus will make timing adjustments correctly in relationship to the throttle opening.

It's not that hard to do. You will need a good multimeter, and you will either need to buy the special torx bit with the indent in the center as the screws holding the TPS have a little *** in the center to keep you from using the standard torx bit. I just used a very narrow small chisel to knock the *** out of the center to gain access to the screws.

What I initially found was the base setting of 750 + or - 50 was close at 748, but the second setting which was supposed to be 750 + or - 50 was way off at a reading of 1150. It takes a bit of fiddling to get it really close, but, not so much to get in range. I was shooting for perfection so it took me a while to get adjusted just right.

Once you have made an adjustment, open the throttle and let it close a couple of times to re confirm your adjustment.

Dale

Taffy, I think it should be in both.

Steve,

Yes, I'm still running mine. I figured someone spent a great deal of time putting this altogether to make things run better all the way around.

So, do you mean you need to set the rpm at 1750. Turn off the motor, and then go about checking the TPS position? I have never put a tach on my bike to see what rpm I have decided to set the idle at. The only time I reduce the idle speed is when I need a bit more resolution when setting the fms.

Dale

Thank You!

D

From the 2004 repair manual pages G-10 & G-11.

ADJUSTING THE POSITION OF THE
THROTTLE SENSOR

NOTE: The idle speed must be correctly
adjusted before you check the position of the
throttle sensor.
– Disconnect the plug and socket connection on the
throttle sensor.
– Connect a multimeter (measuring range ohmsx 1k) to the
blue (+) and the black (–) cable on the throttle sensor
and measure the throttle resistance.
– Multiply this value by 0.15 to obtain the setting for the
throttle sensor.

Example:
Throttle sensor resistance (bl/b) = 5 kilo ohms
Throttle sensor resistance (y/b) = 5 kilo ohmsx 0,15 =
750 ohms± 50 ohms
– Connect the multimeter (measuring range ohmsx 100) to
the yellow (+) and the black (–) cable on the throttle
sensor and measure the throttle sensor resistance with
the throttle grip closed.

According to the above example, this value should be
750 ohms± 50 .

– If the measured value does not correspond to the
setpoint value, loosen the 2 screws (1) and turn the
throttle sensor (2) until the measuring device displays
the setpoint value.
– Fix the throttle sensor in this position by tightening the
screws and check the value again.
-Connect the throttle sensor to the cable tree.

CHECKING THE THROTTLE SENSOR

NOTE: The following measurement must be
performed at a component temperature of
approx. 20°C.

--Disconnect the plug connection on the throttle sensor.
– Connect a multimeter (measuring range . x 1k) to the
blue (+) and the black (–) cable on the throttle sensor.
Throttle sensor resistance: 4 - 6 kilo ohms
– Now connect the multimeter to the yellow (+) and the
black (–) cables on the throttle sensor.
– The resistance should change evenly when the throttle
grip is slowly opened.
Throttle sensor resistance: 0 - 5 kilo ohms±1 kilo ohms
(when the throttle grip is opened)

disregard the little squares, that was supposed to be the symbol for ohms.