Why bother with carb jetting a road bike

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richyrd5
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Re: Why bother with carb jetting a road bike

Post by richyrd5 »

early nc30"s were 110 all round,later ones were 118f/120r..uk ones were,i think,122r/120f..
racingt
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Re: Why bother with carb jetting a road bike

Post by racingt »

I'm no expert but setting float heights helped my 35. I rejetted, inserted 0.5mm shims all round, and cleared the airbox of mice food remnants and droppings. I think clearing out the mice stuff helped the revs above 10,000. Rest certainly helped the flat spot which was very noticeable.
Latest mod is a Tyga system which gives more top end.
But the best mods was suspension setup by MCT.
Neosophist
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Re: Why bother with carb jetting a road bike

Post by Neosophist »

I wouldn't bother with a k n filter for nc30, stock airbox / filter works fine to 99% of cases.

These bikes are quite strung out from the factory, there are limited tuning options available, not like some bikes which ship quite de-tuned and its easy to coax more power.

The carb rebuild guide has all the information on it to get the best settings from your nc30, which isn't far from stock, depending on system maybe 1 size up on the mains, most important things is to get the carbs fully cleaned out, float heights ok and pilot screws set properly.

should run really well and smooth if carbs are in good order with no real flatspots or hesitation.

hows it running now?

if its not broken don't fix it
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todd1996
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Re: Why bother with carb jetting a road bike

Post by todd1996 »

its got very low power from 1000-7000 rpm then the power kicks in like a 2 stroke. gona take it apart and clean it all then maybe have a play around with it.
racingt
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Re: Why bother with carb jetting a road bike

Post by racingt »

Have you ridden another one? Is this one different?
Or perhaps someone could ride yours. To be honest, that may simply be a perfect power delivery.
I know mine doesn't really get out of bed till 7000 then it's happy times.
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GeeTee
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Re: Why bother with carb jetting a road bike

Post by GeeTee »

stock is 115/118

I'm running 118/120 on mine, drilled slides, plus rick's fast road needles with full tyga system, and K&N filter

Possibly a little rich by seat of the pants, but plugs are a good colour and it pulls strongly to redline without flatspots

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