Carb suggestions please!

[Spike16]

i like the polisehed frame look,but i'l too lazy to do it

+1, i just about got my exhaust mount bracket polished and fork tops, but that was a push, could never do a swinger and frame too

[RVFJE]

Removing the flap will probably be responsible for most of your symptoms, the air tray might also be contributing. I would replace these back to standard, and jet the carbs.

Raising the needles won't do much harm, I've only ever had good results. 118 front and 120 rear would be a good start regarding jetting, also check that the pilot screws are set correctly (2.25 turns out).

Stickshift - the air tray basically performs a similar role as the rubber flap in that it's in the same place. However it does allow a much faster air flow to the carbs (for cooling only) and some of this may be getting "forced" into the airbox.
I don't think you can have both installed - it's either one or the other. Is that right?
I have removed the rubber flap and installed the carbon HRC style air tray to try to cool the carbs but the problems I have and the symtoms were the same. Will not pull high revs at high speeds and stutters a lot.
I thought it was fuel starvation so I did the fuel tap mod but that keeps dripping even when Off.
So now I am running the bike with no flap and no air tray with the snorkel installed in the Tyga carbon airbox lid. I will see what happens this Saturday.
BTW mine is NC35.

[Cammo]

Stickshift - the air tray basically performs a similar role as the rubber flap [no it doesn't] in that it's in the same place. However it does allow a much faster air flow to the carbs (for cooling only) and some of this may be getting "forced" into the airbox. [It causes extra turbulence which upsets the carb settings]

I don't think you can have both installed - it's either one or the other. Is that right?
I have removed the rubber flap and installed the carbon HRC style air tray to try to cool the carbs but the problems I have and the symtoms were the same. Will not pull high revs at high speeds and stutters a lot [because it's running lean as!].
I thought it was fuel starvation so I did the fuel tap mod but that keeps dripping even when Off. [No, you need bigger jets to compensate for the extra air getting in]
So now I am running the bike with no flap and no air tray with the snorkel installed in the Tyga carbon airbox lid. I will see what happens this Saturday. [It won't run well].
BTW mine is NC35.

[Cammo]

The air tray shouldn't be used on a road bike in my opinion. I know people do, but it was never meant to cool the carbs, it was designed solely to feed air to the carbs when NO filter or airbox is installed as per the hrc manual (my bike below, take the tank off and that's what you'll see [since fitted with round slides for all you trainspotters out there]).

Using the air tray with the airbox and filter setup can create more good than bad as you (and others!) have found out.

Remove the tray, refit the flap, get it jetted to suit and it'll go hard day and night.

[RVFJE]

No worries mate. I'll put the rubber flap back in and see how she goes.
Just one more question though - if you have no airbox lid and filter but the rubber flap installed you are getting a lot of hot air in there anyway. Is that a problem?
You said the HRC style air tray should not be used on a street bike. Mine is being set up as a track bike. Still does not seem to work anyway!

[royster81]

it was designed solely to feed air to the carbs when NO filter or airbox is installed as per the hrc manual (my bike below, take the tank off and that's what you'll see [since fitted with round slides for all you trainspotters out there]).

hey ,i'm a train spotter and proud lol

[viper_biker]

You said the HRC style air tray should not be used on a street bike.

This is my road NC30, tray doesn't affect it adversly and no wee flap (teehee) at the front and the air-box snorkel is gone,

[royster81]

You said the HRC style air tray should not be used on a street bike.

This is my road NC30, tray doesn't affect it adversly and no wee flap (teehee) at the front and the air-box snorkel is gone,

your bike goes against everything i have read on this forum but...
some say don't touch the snorkel,you pulled yours out...
some say don't cut the filter base ,you chopped yours off and everyone says don't remove the flap,you not only chucked it but put in the HRC tray.....

i have the HRC tray on my road '30 as nothing more than a glorified heat sheild and to be honest i don't even know if it works that well,i have the track bike set up the same as cammos race bike and it works really well,i look forward to getting the rest of the parts now

if smev can get his bike running pretty well then he can try the HRC tray again and if the bike doesn't like it then he knows what to change back.

[superlite]

It's worth mentioning that the NC30 and NC35 carbs are completely different to set-up in race trim. The NC35 carbs are much more willing to cooperate with HRC mods. Not many people run the full NC35 set-up: tray, airbox etc, because the carbs respond well to any increase in airflow due to their velocity stack design.

And velocity stacks are the key (well one of) for the NC30. I don't know how many times people have sold their track NC30s (cheaply!) because they don't run right after butchering the arbox set-up. The age old theory of more air equals more horsepower isn't necessarily true with the little V4s - they are extremely fussy! It's a black art to set-up the NC30 carbs and what works well for one doesn't automatically work for another - not sure why, maybe altitude, humidity, engine manufacturing tellerences, etc. Who knows.

NC35 carbs are definitely the easier option, and HRC parts are cheaper and a little easier to come by than their NC30 counterparts. I quite like the challenge of setting up my NC30 carbs though. Infact, I think I prefer working on it to actually hitting the track! That's a little sad, but I love my carbs dearly - you should see the collection of carbs, needles, jets, etc that Stickshift and I have! There's no room in my garage because of the carbs littering the floor! Weren't you supposed to collect them Stickshift

[royster81]

There's no room in my garage because of the carbs littering the floor! Weren't you supposed to collect them Stickshift

ahem ,if old shiftyboy doesn't want them i could be called into action to clear the space ali...