wont pull

[NorfolkrobA2]

hi everyone,im hoping someone can help me with the running of my 78 z1000,fires up fine,ticks over good,revs ok,so today i thought i would give it its 1st run in a long time...part throttle seems good,but when i acclerate it bogs big time.....now..im running stock pilot,112.5 mains,k&n filters and air corrector kit....what have i done wrong??...can someone give me a pointer please,as im gagging to give this ol girl a good shakedown....

[kev edwards]

You may need to use larger pilot jets, are you using 28 or 26mm carbs, if 26mm you could open the fuel screws a bit, also are your float levels correct.

[NorfolkrobA2]

hi kev,im using vm26 at mo,but i have just discovered that the pod filters im using are covering the air inlet ports,like where the air correctors fit,totally blocking them,have fitted another set i had which are open,not blocking the ports...i have assumed the floats are ok,big mistake i know,(basically i forgot)...doh !!!!,but i am aiming to take off the carbs again to replace the cables,found the throttle to be heavy,so im changing the cables just in case..what size pilots do you reckon i should go up to...

[zed1015]

The pilot jets DO NOT need changing from stock and unless you have jet blockages or the ignition advancer is sticking i would guess your "K&N's" are not the genuine article ? and the issue is with those.
You should not use cheap pods but genuine K&N. S&B, APE,RamAir. Unifilter or Pipercross.
Copies do not flow enough air, can cause rich running , power loss and in most cases are more restrictive than the airbox.
Try running it without them fitted to see if the issue is resolved.
Also have you got the air correctors in the correct locations.
Some fuel mixture screw type vm26 carb banks are made up of all left hand bodies and the jet positions need to be all at 4 o'clock if this is the case.

[NorfolkrobA2]

soon find out tomorrow,but thats good news not to change the stock pilots tho....a/corr jets are in the correct position,in fact someone had already tapped the carbs out to suit....just hope it dont rain tho lol...

[zed1015]

...a/corr jets are in the correct position,in fact someone had already tapped the carbs out to suit..

You should still check that the carbs are handed though and not a left hand body set despite them already being tapped just to be 100% sure.
The Left hand body issue with the fuel mix screw type 26mm sets is and was not widely known .
Even the original Ledar kit instructions made no mention of them so there are quite a few bkes about with one pair of carbs having jets in the pilot air bleed and running over rich and bogging on cylinders 3 and 4.

[kev edwards]

My own 26mm pumpers are all left handed, so it's best to check.

[NorfolkrobA2]

i do know that the corr jets should be right,because you have to fit them opposite the air screw which mine are,anyway,just took it out for a quick test,much much better but still bogging when cracked open,will pull,but you have to increase gradually.....raise needles ???

[NorfolkrobA2]

right,carbs off again,throttle valves needles out and the jet circlip is one notch above bottom...should i go higher ?

[zed1015]

You should have done the choke test first to see if it's a lean or rich condition.
Feather the choke at the point of the hestitation and if it improves you need more fuel and if it worsens you need less.
Either way you should only make small adjustments so one notch if it needs it..