Hi, was at rockingham on sunday and my nc30 would not rev past 12500. It has no ignition barrel its wired into the kill switch. Done the resistor mod to my cdi and i have a digital dash. Any help would be greatly appreciated. Thanks.

Did this happen in all gears? Or was it just the 180km/h speed limiter?

happened in all gears

Probably to do with lack of fuel, either through the fuel tap/vacuum not working properly, jets too small, or too much air getting in (airbox/filter mods?).

Continious WOT can cause fuel starvation but that would cuase it to stutter at high revs? HRC recommend disabling the vaccum unit to rectify that.

Apart from that i'm stumped. :/

Does the power disappear bang on 12500 in all gears, or is it 'fluffy'? Sounds like it may be running lean. As Cammo says, I'd suspect the airbox set-up first. A standard fuel tap would usually only cause some hesitation, and would still get to the redline (eventually).

no more power coming out of the engine at 12500. sounds like the engine is maxing out. I have 122.5 front and 125 rear jets with hrc exhaust system drilled slides and 1mm raised needles

is it hitting the limiter?
can it hit the limiter in neutral under no load..or even flash up 13l revs?

(not that I agree with revving the nuts off stationary bikes..it might show whether this is a tacho calibration or rev lmit issue.)

It used to go past 12500 when i had the bike as a road bike. But now since I've done a lot of work to it as a track bike it will hit the limiter at 12500, i don't know why. Is there any connection between getting rid of the ignition barrel and this problem occurring?

Shouldn't do. I recently did the same mod and the bikes fine. I'td either run or not at all if you did it wrong