Question on main jets .........

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SilverSurfer
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Question on main jets .........

Post by SilverSurfer » Mon Oct 08, 2012 10:26 pm

Hi again i have removed my carbs on my nc30 and found that all the mainjets are 106 (Front and Rear).
Now my question is if it can cause the bike to struggle when accelerating and at topend. it seems like it should be faster :? but it`s like i`m on a 125cc when punching it :x does anyone have a answer?

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Re: Question on main jets .........

Post by bikemonkey » Mon Oct 08, 2012 10:32 pm

Definitely should not be 106's, they were 115 front and 118 rear as standard.

Someone may have had a restrictor kit in there before you had the bike and re-jetted to suit.

That's very lean.

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Re: Question on main jets .........

Post by VFRkieran » Mon Oct 08, 2012 10:36 pm

That is really lean! Even the k model NC30 ran 110's as stock and that is considered to be too lean.

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Re: Question on main jets .........

Post by porndoguk » Mon Oct 08, 2012 11:25 pm

VFRkieran wrote:That is really lean! Even the k model NC30 ran 110's as stock and that is considered to be too lean.
+1

whack some 115 in the front and 118 in the rear,

having said that after a recent dyno trip there is no difference in temps and air fuel ratio between the front and rears and is fine to run all 4 the same,
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v0latile
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Re: Question on main jets .........

Post by v0latile » Tue Oct 09, 2012 8:50 am

porndoguk wrote: +1

whack some 115 in the front and 118 in the rear,

having said that after a recent dyno trip there is no difference in temps and air fuel ratio between the front and rears and is fine to run all 4 the same,
i run 118/120 is it worth changing to 120's all round when I next have my carbs off. I run standard with a straight through can.

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Re: Question on main jets .........

Post by Drunkn Munky » Tue Oct 09, 2012 9:15 am

Before you go ordering jets you might want to confirm you actually have nc30 carbs fitted and not nc35 carbs which run 108's as stock. Ok 106 is still low but if your jetting for 30 carbs when you actually have 35 carbs your wasting your time and money.
You may also need to take into account you live in SA, the jetting advice your getting here is based on UK weather and altitude and that may well be different to where you live, any other SA NC30 owners on here?

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Re: Question on main jets .........

Post by SilverSurfer » Wed Oct 10, 2012 11:55 am

I think they are nc 30 carbs coz the part that you have to remove to get to the needles are metal and not plastic like the nc 35 carbs, the funny thing is it doesn`t struggle to start at all even in cold weather (without choke), it`s only when punching it that it`s weak.

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Re: Question on main jets .........

Post by CMSMJ1 » Wed Oct 10, 2012 12:26 pm

You definitely need to factor in altitude....where in Saffa are you?

If you are up on the plains in Jo'burg Pretoria area then that is pretty fecking high so you'll need smaller jets.

Best bet..get it dyno tested and see what the air fuel mix is like.

If you live on the coast and bought it from up there..it will need changing.
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Re: Question on main jets .........

Post by speedy231278 » Wed Oct 10, 2012 12:51 pm

SilverSurfer wrote:I think they are nc 30 carbs coz the part that you have to remove to get to the needles are metal and not plastic like the nc 35 carbs, the funny thing is it doesn`t struggle to start at all even in cold weather (without choke), it`s only when punching it that it`s weak.
Not only that, the air screws on the NC35 carbs are underneath and the float bowls are shaped around them. They are on the side on the NC30, so the float bowl doesn't have the recess. That's a fun place to leave the flaming things for us NC35 owners, as if having three balancing screws underneath wasn't bad enough!
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Re: Question on main jets .........

Post by SilverSurfer » Wed Oct 10, 2012 2:13 pm

i`m in the north west province 100km from Pretoria, so what ur saying is that 106 should be fine for where i am? or should i go ahead and change them to STD jets?

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