ok - I'm totally new to all this biking malarkie, especially when it comes to the mechanical side of things (I've enrolled in a bike mechanic college course, but till then...)
on a gk76a, 1990, I've managed to replace all the plugs to get her running (a bit) and had some problems with the reg/rec wiring (which I had an electrician sort out) but she revs very poorly between 4-6k rpm... kinda spluttering and struggling in every gear and even neutral, but as soon as she hits 6k, she flies! Is this just a normal power band on the bike, or is mine poorly? currently topping at around 120mph at 13k in 5th... still need a run on a dyno, but any preliminary advice on this would be appreciated. oh... and as you're reading already - can LED indicators be fitted without messing with the flash unit?

Sounds like you have carb troubles. Maybe spray in some carb cleaner, see if that helps, but you'll most likely have to renew the float seals etc..
As for 120MPH, that's pretty quick, especially in 5th rather than 6th

LED indicators will work fine as long as they include a resistor, as most CE approved indicators will.

I'd say you got the standard problem of bad carb o'rings.

lal, I prolly meant 6th, as I said, I'm new to all this. And thanks for the info - I'll look into that.

Yeah these bikes are famed for poor running due to the o-rings in the carbs needing replacing making it run way rich, start there and you probably wont be far off.