hi there hope someone can help me,

I've just replaced the engine in my gsxr400 gk73a, with a bandit 400 motor. swapped the intakes, sump and all the bits that needed swapping.

However after bump starting it, it still won't run properly. If i pin the throttle after bumping it the revs barely pick up even with it at the stop and most of the time it will die almost immediately. I've spent hours on it, tried adjusting the idle, choke on/choke off etc but still no joy.

Somebody help me please!!!!

Tried new plugs?

swapped the plugs for the ones out of my old motor , which ran perfectly until the gearbox seized into first

could it be the coils?

try testing all the coild and plug leads and also dont forget the plug caps.

if any of the above are open circuit then replace as they will definetly be causing the problem aslo check your battery voltage

Make sure you got the coils hooked up proper coil on left goes to hole 1-4 coil on right 2-3 or visa versa but not coil one goes to 1-2 thats wrong