CB400SF won't start...

[singkiwi]

Hi all,
Not sure if I can give you enough info for a prognosis but hopefully I'll get some places to look.
I have a 1998 CB400 super four. Not exactly a classic but completely rebuilt into a cafe racer...
I completely stripped and rebuilt everything except the engine (was running)
Replacement carb kit (stock jets)
Removed airbox and used pod filters
Existing loom and ECU
Free flow exhaust

So we tried to fire it up the other night
We have spark
I think we have fuel, although the fuel tap appears to have a small vacuum operated pump which does freely flow(also tried a Ktm tank so gas definitely going in)
The engine turns over it appears to almost run on the starter but does catch and run?

Neutral and side stand switch are ok

Any ideas?
Could the pod filter and exhaust combo be causing this? I'd assume it would run, just badly...
It has two coil packs with 4 HT leads and 4 LT leads. the correct pairs go to the coils but does it matter if I reverse the LT leads on each coil?
Is it a vacuum fuel pump on the petcock? Should fuel run free?

Cheers

 

[singkiwi]

A quick pic...

 

[crazypj]

plug wires go1-4 and 2-3, doesn't matter which way round.
Make sure you have the correct inputs though, could be trying ti fire the wrong cylinder?
It's going to be stupid lean with pods and exhaust, they run lean before you modify anything
Did you apply a vacuum to the fuel tap (petcock)
stick a pipe on it and suck, fuel should flow from outlet and nowhere else

 

[singkiwi]

Did you apply a vacuum to the fuel tap (petcock)
stick a pipe on it and suck, fuel should flow from outlet and nowhere else

Ah that's smart!
Quite confident the plugs are ok, tried reversing them, big backfire...

Cheers

 

[singkiwi]

Fired up almost instantly today.... Gremlins! I cleaned the fuel pump on the petcock, seems clogged after trying a suck test.
Thanks for your help! Cheers

 

[crazypj]

LOL, 8)
sometime 'sucks' works ;D