Administrator
Webteam
MotoGP God
Bikes: 748S, HM1100S, V4SP, Was: DD-A #111
Posts: 13,086
Join Date: Feb 2002
Location: Back in Essex
Mood: Passion Killer
I was going to say that this is sometimes a TPS problem, but you've found it's obviously an issue with the front cylinder - could be somewhere along the spark (coil / lead / plug) but it's also a common problem with the 5.9M ECU as well.
As you've got a spare ECU I would say swap it over and see if it runs with that first, as it's a nice easy way to check.