UK NC carb jetting.....

[pip]

The workshop manual shows 1 shim under the needle, but no indication if 0.5mm or 1.0mm [typical values]

Out of interest, I note that the RC30 main jets [similar V4 motor] are the same way round [richer fronts] as UK NC30, for the UK and rest of the world production, but I don't know about Japan.
The needles and emulsion tubes are the same front/rear.

Cheers

When you say the needles & emulsion tubes are the same front & rear - I don't quite follow.

The parts fiche shows them as being different f&r on uk spec bikes, indeed, mine are.
Or do you mean they are the same orientation on uk & jap bikes (5 hole tubes & 'A' needle in rear - albeit a different needle code).

Cheers, Pip

[speedy231278]

I think he means that RC30s run the same emulsion tubes and needles in both the front and rear carbs.

[arsey30]

I was referring to RC30 being all the same as opposed to NC30 being different F/R.

I will know from the parts list the correct NC30 emulsion tube fitting when I receive my new one in its labelled packet.

[arsey30]

I now have the new front jet holder emulsion tube.

You will see it is the richer 4 hole type, which suggests that the richer needle will also go in the front carbs.

[pip]

I now have the new front jet holder emulsion tube.

You will see it is the richer 4 hole type, which suggests that the richer needle will also go in the front carbs.

Great info

So we now KNOW that the 122 jets & 4 hole tube go to the front 120/5 hole to the rear & think that the richer needle goes to the front.

1 - which is the richer needle - A or B
2 - does anyone KNOW whether the A or B needle goes to the front on uk spec bikes

Strange how Honda have left the emulsion tubes the same but (increased &) swapped the mains f&r!

Pip

[porndoguk]

You need to measure the needles to determine the richness persay, the thinner would be the richer of the two but you would need to compare them as they might be thinner/wider at different parts

[Neosophist]

Indeed, as I mentioned earlier the tubes with the most holes go in the rear.

The UK emulsion tubes while having the same number of holes are not the same as the JDM emulsion tubes.



From cammo's guide but you can see the holes are all in a line.

The UK ones are staggered more I believe.

viewtopic.php?f=24&t=30515&start=50

this thread covered much of the same thing...

I cant remember what the uk needles are marked up as, if you post the markings up it might jog my memorys as to which way around they go.

[pip]

Uk needles are;
J1G A & J1G B.

Tis true, the uk 5 hole tubes have the lower (well, upper!) holes at 90* to the two rows of four

So far I have fitted the A needles in the rear carbs as per Jap bike.

Pip

[Neosophist]

From memory A needles go in the 122 jets
B needles go in the 120s

[zelovski]

Good evening Guys,

I may be dull but i think my case is a little special : I have a 92 JDM bike with carbs which must be french spec ones.

Main jets are 120 / 122, needles are J3UF / J3UG, 4 / 5 holes emulsion tubes, red ring slides with 3 holes.

I'm running a full system.

What would be your advice regarding front / rear positons ?

Cheers,

Matthieu