General EXUP question, and rough running problem

[AyJay]

When the EXUP opens, the ignition timing changes. I think this is what makes it run so badly when the EXUP isn't working properly. It isn't gas flow that makes it feel so rough, that just lowers the power at low revs, it's the ignition.


Also, just so's you know the TPS causes a surging feeling and it feels like the bike is momentarily cutting out, but in a gentle way. The TMAX 500 scooter's TPS is a straight swap. I actually bought a rusted up and knackered set of carbs off a chap for £20 just for that one 140 quid part. If only he knew....