[Dukedesmo]

IMHO the reason the TPS works so well is that, although the map for the ignitech is programmable by RPM or RPM and TPS, if you programme by RPM alone then the transition between advance happens too intermittently/randomly when around the RPM switch point due to the engine RPM 'fluctuation' during the cycle.

If you watch the rev counter (the digital one in the Ignitech software) you will see the numbers fluctuating from cycle to cycle at steady throttle, especially at lower RPM due to the uneven firing sequence and this is worsened by having a light flywheel as mine does.

So, if you are switching from say, a 5 degrees advance to 8 degrees at 1500 RPM then what happens around that speed is the ignition switches randomly between advances causing it to be a bit on/off, in my experience.

Adding a TPS to the equation makes things more reliable due to not relying on just the fluctuating RPM reading but also the throttle position which will remain steady at steady throttle and not subject to 'pulsing' whilst the engine is running plus, cracking open the throttle will give you more advance, quicker.

If you have the Ignitech programme, open up a map and then switch between 'only RPM' and 'RPM and TPS' especially in 3D mode for a good representation.

I have switched between an RPM only and RPM and TPS programme in the bike, back to back and can definitely say it is an improvement at low speed running, no real difference at higher speeds as you're already at maximum advance anyway.

Don't know what an air flow sensor might add, if anything?