NC30 carby jetting - DIY guide

[yazza54]

I just stripped my carbs down and cleaned the jetting and float. I've refitted the carbs back on with new mounting rubbers and all went well. I can get the bike running with the air box off using a spray of easy start down each inlet and a temporary fuel supply. it won't start with the air box and filter on. Curiously whilst running fuel started coming up the rear cylinder head breather tube and spraying all over the place! what's going on? Any suggestions? Regards Pete

It's not a breather.... it's the vacuum to your fuel tap. If your just using a temporary gravity fed fuel supply for fettling then block this pipe.

[thebugser]

Thanks for that advice about the vacuum. today I took all the plugs out cleaned all the fuel off as they are new plugs and refitted them. Still can't get the bike to start with the air box in place. I'm only starting it with the choke open and no throttle. Im at a loss now as to what to do next. regards Pete

[yazza54]

How is your temp fuel supply connected? The fuel needs to be gravity feeding the pipe to the carbs. Were the plugs wet when you removed them?

[DrunkenMistake]

Sorry if this has been covered, but what size holes should the washers be? I dont want to have to pull the carbs apart to get a washer for a rough idea of the size, then reassemble so I can ride into the city to get some washers haha

Bump bump
I need the internal diameter and external diameter of the needle washers, pleaseee

[yazza54]

Sorry if this has been covered, but what size holes should the washers be? I dont want to have to pull the carbs apart to get a washer for a rough idea of the size, then reassemble so I can ride into the city to get some washers haha

Bump bump
I need the internal diameter and external diameter of the needle washers, pleaseee

Just ask rick oliver

[yazza54]

ricknc30@gmail.com

[porndoguk]

0.5MM THICK
3MM INTERNAL DIAMETER
7MM EXTERNAL DIAMETER

[yazza54]

Whatta guy

[DrunkenMistake]

0.5MM THICK
3MM INTERNAL DIAMETER
7MM EXTERNAL DIAMETER

Thanks mate!

[surfer 69-b]

next i fitted some washers to raise the needles (and hrc cdi) and it was cured
the only disadventage is i think i have to close the petrol when i leave it standing (if not i can smel petrol but it didn t flood becouse it always started right away if i forgot to close)

You shouldn't need to turn the fuel tap off just because of these changes. The smell of petrol might be because it's running excessivley rich?

hi guys i have taken the slides out of the carbs , it seems like i had not put the seal in the correct way , this was probably the reason for the smell of petrol when i left the bike standing.
now that i put it correct back together i can leave the feul tap open again

at the moment the bike revs wel through the whole range but if you guy say the springs is the better way to cure the hole i would like to truy this (rest of bike is standard)
groeten michel

I guess the only thing to do is remove the extra washer (1 washer is standard) and see how it goes, or get it dynoed. You can be our guinea pig!

have installed a set of r.o. carb springs , vacuum hose and removed the extra washer i installed earlier , did not put the bike on dino but the bike runs fine
thanks a lot for the info again