Nc30 carb set ups for track bike, advice wanted

[lukemillar]

Don't drill main jets out, buy the correct sized keihin jets, you'll need around 145's for nc30 HRC carbs.

Yep and 200 is HUGE and far too big. I think mine is currently running:

MJ: 145F, 147.5R
PJ: #40 all round
Needles: 8ZG with no washers
Pilot screws: 2.0 turns out
Slides: NC24 non-drilled

But that is with a blueprinted engine and slotted RVF cams. With a standard engine I was just using smaller mains ~142-145

[juggernaut]

Don't drill main jets out, buy the correct sized keihin jets, you'll need around 145's for nc30 HRC carbs.

Yep and 200 is HUGE and far too big. I think mine is currently running:

MJ: 145F, 147.5R
PJ: #40 all round
Needles: 8ZG with no washers
Pilot screws: 2.0 turns out
Slides: NC24 non-drilled

But that is with a blueprinted engine and slotted RVF cams. With a standard engine I was just using smaller mains ~142-145

Is this with an air box lid and std filter? Also what else has been done, under carb scoop? Front part of air tray cut off?
What the full set up you're using?

[Drunkn Munky]

Thats a HRC setup, no box, filter etc and a HRC carb tray

[hunter]

All the specs i posted in that thread are from the micron tuning sheet that i have in my possession,
And yes 200 main jet sounds big But that's what they say.

And yes they do tell you to use a 2mm drill bit.

[Neosophist]

What is it running at present?

Depending on what you have already you won't get a lot of extra power.

Most people think about many cars, they can put on a new exhaust, alter the fuelling and get more power, that is often becuase these cars were designed with more power and tuned down to save fuel etc.

The NC30 was designed to make 59hp, so making more is expensive, the full HRC kit makes more power (circa 78hp) by using bigger jets / open carb (more fuel) but more importantly new cams/pistons/rods and ignition unit, which are the biggest restrictions on power to the bike.

What is your overall bike like now?

There are many other things you can do to make the bike faster around a track.

Suspesnion is the biggest one, a well set up suspension will improve laptimes more than 3hp for most people.
Lighten the bike, loose any weight you don't need, its like gaining power as your not hauling around so much

This includes, GXSR flywheel mod if your running a charging circuit or binning the flywheel if your not.
Lighter wheels
520 chain \ sprockets (pretty standard on track bikes)

Depending on your bike now, id really consider putting any money you might throw at them towards the other things first.. not saying not to do it but the ways above should improve your bike much more noticabally.

[lukemillar]

Don't drill main jets out, buy the correct sized keihin jets, you'll need around 145's for nc30 HRC carbs.

Yep and 200 is HUGE and far too big. I think mine is currently running:

MJ: 145F, 147.5R
PJ: #40 all round
Needles: 8ZG with no washers
Pilot screws: 2.0 turns out
Slides: NC24 non-drilled

But that is with a blueprinted engine and slotted RVF cams. With a standard engine I was just using smaller mains ~142-145

Is this with an air box lid and std filter? Also what else has been done, under carb scoop? Front part of air tray cut off?
What the full set up you're using?

No airbox at all, drilled and modded carb tray as per HRC, foam removed from underside of the tank and a fibreglass air scoop over the radiators. Also using a full TYGA system

All the specs i posted in that thread are from the micron tuning sheet that i have in my possession,
And yes 200 main jet sounds big But that's what they say.

And yes they do tell you to use a 2mm drill bit.

Have you actually run this setup? I'd be curious to hear more

[hunter]

To be honest i can't remember what setting i used it was so long ago.
I later ran mine with my Tont Scott carbs.

[marcus57]

What is it running at present?

Depending on what you have already you won't get a lot of extra power.

Most people think about many cars, they can put on a new exhaust, alter the fuelling and get more power, that is often becuase these cars were designed with more power and tuned down to save fuel etc.

The NC30 was designed to make 59hp, so making more is expensive, the full HRC kit makes more power (circa 78hp) by using bigger jets / open carb (more fuel) but more importantly new cams/pistons/rods and ignition unit, which are the biggest restrictions on power to the bike.

What is your overall bike like now?

There are many other things you can do to make the bike faster around a track.

Suspesnion is the biggest one, a well set up suspension will improve laptimes more than 3hp for most people.
Lighten the bike, loose any weight you don't need, its like gaining power as your not hauling around so much

This includes, GXSR flywheel mod if your running a charging circuit or binning the flywheel if your not.
Lighter wheels
520 chain \ sprockets (pretty standard on track bikes)

Depending on your bike now, id really consider putting any money you might throw at them towards the other things first.. not saying not to do it but the ways above should improve your bike much more noticabally.

I agree with all the above but , viewtopic.php?f=62&t=39113

The engine is standard apart from quitening gears removed , total loss and an ignitech.

I have ordered the hrc kit from Rick O now

[28hodge]

Marcus I too have the full micron system, which is the same as yours I think 4into 1. I've put the full Hrc carbs onto the bike with the fibreglass tray underneath them and drilled carb tray, short stacks from RO etc, I was going to get it dyno'd to see what difference the Hrc carbs made as it made 62 with standard induction, full airbox filter etc.

Unfortunately I broke my foot so didn't get much further but I'm hoping I can eek out 65ish so looking for a 3bhp gain, between us we should be able to get a good base setting for the setup.

A good fresh 520 chain helps as a knackered old chain robs rear wheel bhp something chronic from what my dyno guy told me, and fair fucks to the lad as he finished 3rd in this years newcomers at the Manx in the twins, so he knows his schizzle!

Be good to see how you get on with yours good luck with it pal.

[marcus57]

Sweet , should make things a little easier.

Have you ridden it since you fitted the kit to it? I have ordered a load of different sized jets and i was going to start in the middle with them as to me that makes sense , what size have you fitted?