What year is your 4s? Mine is an 04 with a 5AM ecu and I can only set the TPS with software.

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03 5.9 computer, suppose to be able to set it with the mv readings at the tps. Right now I've got it back to a good idle and I suspect the mv readings are about 320 or so. I didn't take time to check it when I just got back but stopped and turned it down a bit on the road. Fun to ride without all the plastics.

 

From the Service manual for my '05 ST4s:

Adjusting the throttle position
sensor
Insert the Memory Card into the
tester and access the "Throttle
position sensor" function in the
“Auxiliaries” menu. You can now
read the throttle position sensor
output voltage with the MASTER
throttle completely closed. The
reference value is 150 mV ±15.
If you encounter different values,
loosen screws (14) fixing the throttle
position sensor and, keeping the
MASTER throttle in its fully closed
position, turn the position sensor until
obtaining the prescribed reading.
Tighten throttle position sensor
screws (14).
Disconnect the Mathesis tester
from the throttle position sensor
and reconnect this latter to the
motorcycle wiring.

Adjustment of idle speed fuel -
air mixture ratio
Connect Mathesis power cable (2)
socket (B) to the motorcycle
diagnosis outlet (15).
Enter the “Autodiagnosis” menu and
select the motorcycle model.
If the procedure is performed
correctly the tester will connect up to
the motorcycle engine control unit.
Select the “Read parameters”
function.
Now choose the “Throttle position
sensor check“function.
Turn MASTER throttle adjuster
screw (9) until obtaining the following
throttle angle and voltage values: 2.6°
(3° for USA version).
If it has been disconnected, return the
throttle control cable into its pulley to
activate the throttle control and adjust
the travel (see “Adjusting the throttle
control cable” Sect. D 4).
Turn adjuster screw (9) until reading
the previously set throttle angle and
voltage values.

I know you probably don't have a Mathesis, but the rest of the info I found very useful. If you have VDST and a multimeter you should be able to make the adjustments.

Hope it helps.

 

520-520 mV is very high! The Biker Boy site says to use 423 mV or 2.6 degrees of throttle angle (if you have VDST or Ducati Diag). Those are the numbers I use and it always works out fine. Also make sure you have disconnected the fast idle and throttle cables, plus the rear TB linkage before setting that 150 mV or 0 degree setting. It is very sensitive and any restriction to that forward TB butterfly seating fully will mess up the rest of the settings. No shortcut with that step, or really any of the following steps...

 

The base 150mV setting is thee improtant one as it baselines the map. The idle stop screw setting is more of a recommendation. Mine is supposed to be 420mV. At that value, the bike sounds like it is on a 'high idle' at a stoplight. Something just shy of 1,000rpm sits better with me. You will also see that the idle speed varies between countries.

I don't believe the throttle cable is different between the ST models. Just lengthen it until it doesn't bump the revs up. Also, check the routing. I can't remember off hand whether it should go inside or outside the fork, but mine was routed wrong causing too much flex. I do like my throttle to have the minimum slack.

Have a good one.

 

thanks fellows! Tony, I've found what you found with the 420mV. I just set it by ear since I got the 150mV. Best!

 

Right on! Enjoy it.

Have a good one.

 

If it sounds good, it is good.

pg
DD

 

that's the way the Black man I worked for as a kid in a mechanic shop did things. By ear! And he was the best. Haywood Thompson, quite the individual.

 

Take her for a ride, that always clears things up.

 

I like the way you think Max!