Hey mate. From my understanding, the GPS splice is to allow more ignition advance in 4th, 5th and 6th. PGM has different ignition curves for each gear. 1st and 2nd are considered too advanced for high load (4th 5th 6th) but 3rd is a safer option.
The PGM splice (where you give 12v to the orange wire from the black wire from memory) keeps the power valve open all the way to redline. From factory the PGM closes the valve at 10000rpm (or there abouts) to choke the engine and limit performance to meet the standard when the bike was made.
So the PGM splice will give full power every gear.
The GPS splice will give more power in 4th 5th and 6th. 1st 2nd 3rd remain unchanged.
You need to do both to get the absolute best.
NB you need to be using GOOD fuel if you are to do the PGM splice. 98RON or better or you may detonate the engine in higher gears.
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