First which bike is it? I have a 2001 X1 Lightning, with Forcewinder and Supertrapp pipe.
What I do is ,
1) Plug in diagnostics cable , make sure ECM spy has the COM port, turn on buell ignition and runstop set to run, push keys button on the ECMspy
make a note of the degrees on the main screen for the TPS, and the AFV value. Save ECM data with date as title so as to revert if things go bad. Note codes and Clear faults.
2) Open and close the throttle fully so it says 85° (fully open) and whatever shut. Do this three times and make sure the voltage is within a close tolerance of each shut (0.1 is ok , anything higher says sensor could be faulty)
3) Hold throttle shut, and wind back the throttle screw until it is just past 0°.
4) Reset the TPS.
5) Check on main screen that the throttle says 0° and wind the throttle screw on until it says 5.2 to 5.6 °.
6) Start engine and do NOT do anything until "engine enrichment" on the main page reaches 100% or lower and the "engine temperature" is 130°C or above
, I let it get to about 150-160°C which coincides usually with enrichment at 100% or lower. The engine could be running at 1300rpm or so, but don't panic.
7) Adjust the warm idle (once "engine enrichment" on the main page reaches 100% or lower AND the "engine temperature" is 130°C or above) to 1050-1150rpm. Save ECM data for reference asa date and post tps reference. (i.e. X1-010609-TPS.txt etc.)
8) crack open a beer, job done.
This should start fine the next time.....
Source : - pash (good detail mate) viewtopic.php?f=17&t=13&start=0
Buell X1 lightning 2001 (back in the UK , come on DVLA ,give me back the V5!) & Santa Cruz Blur (too fat to ride)