Originally Posted by Air_Cooled_Nut
Find out how they do it and report back. I'd like to know more details.
Aye Aye Skipper, here's my report. VDST software from TechnoResearch is now called Centurion-S and sells for $230 Yankee Greenbacks. This gives you a software application (Windows only) and a cable to interface with your bike. The application is copy protected thru the dongle built into the cable.
I am not a peddler for this product, just a happy user. In short, when you change an ECU, which was my case, the replacement ECU needs to know the exact resistance value in the TPS.
My application was on a Brutale 1090RR after I bought the OEM titanium exhaust with shorty Arrow muffler which included a race ECU. Things might be a bit different on a Duc (I have a Paul Smart) but have not needed to use VDST on the Duc.
Please note, because I live on an island in Puget Sound, taking the Brutale to the nearest dealer would have been two round trips on a ferry and consumed about 10 hours of travel time. Buying the VDST for one simple install of the ECU made sense to me. I have not used the software since.
Upon hooking up the interface cable, launching VDST, and turning on the bike's ignition, VDST read the ECU and then "knew" the throttle shaft angle on my Brutale was equal to 2.4 degrees when the throttle was closed and resting on the idle stop screw(s). However, since all bikes have a very slight variations in potentiometers and and very slight differences in the exact throttle shaft angle at idle, the exact resistance value in ohms varies from bike to bike. Upon moving the throttle, VDST would display the changes in the throttle angle. When closed, VDST always showed the 2.4 degree value.
To set the TPS, I was instructed to click on a screwdriver icon; VDST went and read the TPS resistance and stored it in the ECU.
To simplify the air/fuel calculations, VDST simply reads the exact TPS resistance value and reports that to the ECU and the ECU now uses that value as the zero point for a closed throttle.
If you have an multi gas analyzer, you can use VDST for far more than simply setting the zero point on the TPS. I do not have the tools or training to fiddle with A/F mapping or tweaking the ECU and unless you have a unique need as I did, I strongly suggest you take the bike to qualified mechanic to set your TPS.