NC30 base carb setting without air filter etc

[VFRkieran]

I think we better ship this guy off to japan to work for HRC as he is obviously some sort of fueling guru that knows a sight more than anybody on here.

I wonder how long before that motor goes bang...

[kevprojex]

As a start point with the lid fitted and no air filter i would try 135 mains if this helps. a lot of dyno jet kits run very small mains when they supply the knock in blanking plugs for the air jets,eg a 600 srad runs 127/125 mains stock and 107/106 mains when the air jet has been blanked off, but they run very rich untill you get the rpm up.

[thunderace]

As a start point with the lid fitted and no air filter i would try 135 mains if this helps. a lot of dyno jet kits run very small mains when they supply the knock in blanking plugs for the air jets,eg a 600 srad runs 127/125 mains stock and 107/106 mains when the air jet has been blanked off, but they run very rich untill you get the rpm up.

The SRAD is a completely different beast to the NC30. V4s are a lot harder to balance the fuel/air ratio at the best of times than an IL4. Removing the air filter on a V4 is just asking for trouble. I don't condone it on any bike full stop, I've seen too many engines fucked because of what's been drawn inside through the lack of a barrier.

By all means, fit something less restrictive but for the love of sanity don't run with nothing at all. Even HRC use a mesh to prevent stones, tarmac chips, etc. getting in.

[james66]

its just down to correcting the fuelling + will be ok again, nc's are no different

Yes OK, if you say so You do need a proper set up on any bike to prevent ingress of nasties if nothing else.

But you obviously know a lot more than we do, even the seasoned racers among us, so get on with it and let us know how much the re-build costs you when your engine has swallowed something it shouldn't.

I can probably count on one hand the amount of 400 guys in the bemsee 400 paddock who run air filters, i know because im one of the 400 riders

Yes if a stone is swallowed it wont be nice but most of the times that only happens if you end up in the gravel which you shouldnt try + restart with at least checking airbox + carbs for stones

Also if you guys knew what you were talking about you would know about the different airbox setups from the likes of RLR, dyno-pro + funny enough HRC, these are all race setups with out air filters

Re-builds are cheap, I build enough V4 + cbr400 engines to know

I think we better ship this guy off to japan to work for HRC as he is obviously some sort of fueling guru that knows a sight more than anybody on here.

I wonder how long before that motor goes bang...

I never said i knew more than anyone on here i just know more than some, fuelling isnt a difficult thing to learn + as for your HRC comment, countless people that are just as able to setup bikes + cars as the setup guys at HRC + theres products out there for the nc30/35 that are superior to what hrc produced so i dont quite get why people still sit on HRC this HRC that for these bikes any more, HRC never got as much power out of the 400's as what many of us are getting today

Cammo + Kevprojex - Thank you for you input, thats exactly what i was after, not comments from people who either doubt or dont have a clue, you both clearly know + understand Thank you

[thunderace]

Well I bow down to your obvious superiority in these matters. Obviously running a race team has done nothing to increase my knowledge and maybe I should give it up along with some of the other racers who have posted here.

Come on guys, lets go for a beer and think about which career path to pursue next

[james66]

Ok so it seems that anyone else who knows something + anyone who is not prepared to do what your saying or suggesting is wrong + im seems your also every racer running without an air filter is wrong, i didnt once say there wouldnt be a mesh, there is a mesh at the airbox entry behind the snorkel

I do understand what you are saying but i think you also need to see what im saying + asking

[thunderace]

Where have I said you are wrong? You asked for opinions and you got mine. What's the problem? Do what you like, it's your bike and your money. I personally couldn't give a fuck what you do. Just don't come whinging on here if it all goes tits up.

Next time I won't even bother offering you the benefit of my years of experience.

[Drunkn Munky]

I have to agree here, none of my V4 trackbikes have ever run a filter, or a stock airbox for that matter. I see nothing wrong with it unless as stated you take a trip to the kitty litter.
I can see where your coming from with this but why not just stick to a known working setup such as what RLR are using? You've got the airbox there so thats the cost out of the way, the rest is mods you can do for free so why mess about.

As for people opting to run HRC setups, i cant speak for everyone but i do it because i want to, if it was good enough for HRC to get high 70's from the bike then its good enough for me. Personally i dont get on with the so called ram air setups but i can see why most of the grid use it.

But i have to say im strugling to understand why your on here asking for settings to run a standard box with no filter when 1. you clearly know what your on about and 2. you've got better kit (RLR box) sitting there waiting to go.

Maybe some people jumped the gun here but ive lost count the amount of times people have come on here saying ive ripped the air filter out and what size jets do i need?, in general it doesnt work without a lot of extra work and dyno time.

[VFRkieran]

its just down to correcting the fuelling + will be ok again, nc's are no different

I think we better ship this guy off to japan to work for HRC as he is obviously some sort of fueling guru that knows a sight more than anybody on here.

I wonder how long before that motor goes bang...

I never said i knew more than anyone on here i just know more than some, fuelling isnt a difficult thing to learn + as for your HRC comment, countless people that are just as able to setup bikes + cars as the setup guys at HRC + theres products out there for the nc30/35 that are superior to what hrc produced so i dont quite get why people still sit on HRC this HRC that for these bikes any more, HRC never got as much power out of the 400's as what many of us are getting today

Cammo + Kevprojex - Thank you for you input, thats exactly what i was after, not comments from people who either doubt or dont have a clue, you both clearly know + understand Thank you

The thing is you obviously know a fair bit about fueling but your coming on here asking for advice and when somebody gives you said advice your telling them they are wrong even though there are plenty of really experienced racers on here who have set up bikes properly and reliably for years. Also the comment about HRC setups being not as good, i dont see where you get the idea that a factory team that spent millions building these bikes are wrong, people may be getting more HP nowerdays but i bet that a HRC setup bike is much more useable and reliable than the ticking timebomb your building!
Anyway i dont have anything noteworthy to contribute to this thread so i will keep out. But my advice for using this forum is dont go telling the people with years of experience they are wrong without any hard evidence to back it up, this is a nice forum and arrogant people dont fit in well...

[scooble]

I am in the process of setting up my my NC30 which I have just re-built as it was leaking oil from the head and the valve stem seals needed replacing (twice - don't buy chinese copies!).
Anyway, whilst the heads were off, I cleaned up all the rough castings (which there were many) in the inlets and exhaust (also removed some nasty blobby welds in the bolt on manifold). I am running a Yamamto system with a one off silncer by a local company. I have a dual foam filter instead of the paper one and running 118/120 MJ combo (also running 1mm shims under the needles and the diaphragm hole drilled to 2.5mm). It does feel as though that there is a massive flat spot in the midrange, and only starts to get going at around 9k. This was confirmed when I stuck it on a dyno on sunday at the Ace Cafe run in Brighton, unfortunatley, they didn't have any gas analysis though, but it did produce a suprising 59hp at the back wheel.
I suspect that its running too lean at the moment, but I am more concerned about the massive flat spot below 9k.
I do have a set of short stacks, but not fitted them yet, but I was wondering if the stacks would help with filling in the midrange hole. Of course I need to get it stuck on the dyno again to get it set up correctly, but I was wondering what might be a good base setting to start from whilst using the short stacks.