does it have a spark on 2+3? 1+4 use a independant pick up and so do 2+3 also they have a coil shared between the two 1+4 on the same and 2+3 aswell.usually a problem like this is a sparking problem as if it was say 1+2 not running it could be anything.if you have already put new coils on it i would check the pick ups next they are on the right hand side i think on this model iside the crankcase cover.if you havent tried new coils firstly try to swap the coil for 1+4 for the other coil and also the Low tension leads and see if it runs on 2+3 and not 1+4 this will tell you straight away.i have a diploma from suzuki :)
adam bike doctor
December 2009
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