Setting up my mk3

[pmac]

Hi all
Been playing around with the carb settings on my mk3 today, but there is a couple of strange things going on with it!
The air/mixture screw doesn't seem to make any difference to the running of the bike, you can wind it fully in or out and the bike will still tick over and run the same. The bike will also tick over and run the same with the choke on or off (runs slightly better with choke on and ticks over a bit quicker). If you rev the bike hard in neutral it pops and back fires on run down. The bike will also hold its revs for a couple of seconds when you pull up, but this improves when the choke is on.
The bike is a mk3 with active reeds, full DEP pipe and a moto air filter. The carb is standard. I have rebuilt carb and fitted new inlet manifold and crank seal.
I hope some one can shed some light on this.
Thanks in advance
pmac.

[colinthum]

hi ive just had the same thing with mine.have you re-jetted it,taken the funnel out of the air filter box,and drilled some extra holes in the box.i did this and its like

[pmac]

Thanks for the advice colinthum, I,ve got it running ok at the moment, but not brilliant, what jets are you using, and what are your needle position and air screw setting. I have removed the snorkle from the air box, but have not drilled any holes in it. It seems to run better with a standard plug in it, rather than the expensive racing one!. Any advice greatly appreciated.
Thanks Pmac.

[CRMoto]

Sounds like it is running very lean?? Possible air leak on inlet side somewhere! Be careful not to melt it, wouldn't ride it too much like that!! My bike holds revs just before I have to go on reserve (lean!)

[colinthum]

hi ive just had the same thing with mine.have you re-jetted it,taken the funnel out of the air filter box,and drilled some extra holes in the box.i did this and its like

pilot 50 main 160 ngk raceing plug (new off ebay about £4 inc postage)dont forget to check the plug colour. you can check for air leaks by starting the bike let it tickover spray all around the carb and reed block with wd40,if she revs up youve got a leak!is it lumpy all the time or just lower revs,if just on lower revs check the reeds are not bent or damaged.hope this helps colin

[colinthum]

hi ive just had the same thing with mine.have you re-jetted it,taken the funnel out of the air filter box,and drilled some extra holes in the box.i did this and its like

pilot 50 main 160 ngk raceing plug (new off ebay about £4 inc postage)dont forget to check the plug colour. you can check for air leaks by starting the bike let it tickover spray all around the carb and reed block with wd40,if she revs up youve got a leak!is it lumpy all the time or just lower revs,if just on lower revs check the reeds are not bent or damaged.hope this helps colin

neadle setting center,air screw all the way in 3 turns out