Not starting !!!

[z1000puddin]

Guys
I need a bit of help here

I have just finished fitting a new gearbox to my 1075 zed
I have spark at the new plugs
I have compression @ 150 across all pots
Fully charged battery
Dyna ignition & dyna coils
29mm smoothbores

I have only had a loud backfire and then nothing????

Any pointers to where I need to start checking 👿😩
Stu

[steve bowdler]

Fuel Supply good ?

[z1bman]

was it running ok before you removed the engine? did you just part the cases & not touch the top end? check your coils & ht leads or wired correctly

[z1000puddin]

was it running ok before you removed the engine? did you just part the cases & not touch the top end? check your coils & ht leads or wired correctly

It was running well before I stripped it
The barrels were left on. The head was removed & All the valves were left in place & I checked the clearances were all 4 thou on reassembly
The HT leads are all numbered and were hung to the front
I tried swapping the black and green coil wires but no difference

There is fuel in the bores but there doesn't seem to be a great deal as the plugs are not wet.
I tried a naked flame into the plug hole and it did cause a flame out

Confused or what

I may have to go back to the start and double check

Stu

[z1bman]

backfiring it normally associated with ignition or valve timing but your compression is good so i would doubt it would be down to that but it would wise to double check it

[garyd]

Check your spark is firing at the right time.

I had this years ago when I fitted a Z1100 ignition plate to a GPz1100 by accident.

[Ginger Bear]

Does sound like your ignition timing may be 180 degrees out. But as you say, you've already tried swapping the ignition wires around.

[1962royp]

try swapping the coil power leads over from one coil to the other if its 180 out it will either backfire or run.

[z1000puddin]

Thanks guys for all the relevant pointers.
I got the old girl back to life the night.

My problem was the black Bob Weight spacer on the dyna ignition.
The advance weights were not correctly located in the 2 grooves😳😳😳
Started first prod of the button.

I am still not 100% happy as it seems to run better with the choke fully on ??
It is still popping & farting with the choke off.
I got fed up with it tonight & I will have a further look tomorrow

Stu