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Re: cbr400 NC23 ram air..........

Posted: Tue Jan 12, 2010 10:37 pm
by bourney
Wozza wrote:Yeah that's an NC29 airbox.

There should be two pipes next to each other at the front of the airbox that slot into two holes on the inside of the frame near the headstock.
You have the pipes but they don't reach the holes?

Bang on mate.

I have 2 pipes coming out of the airbox yes.

The ends of the pipe are shaped to slot into either the frame or another pipe. However, with the box bolted up theres no way the pipes will reach the frame.
I would get some photos of the box bolted in but the carbs are out atm.

I'll take some pics tomorrow and just position the box as best as possible i think.

Re: cbr400 NC23 ram air..........

Posted: Wed Jan 13, 2010 1:23 am
by Wozza
Yeah sounds odd, will wait for your photo!

Re: cbr400 NC23 ram air..........

Posted: Thu Jan 28, 2010 4:09 pm
by jac_is_smiling
Hey bourney, sorry to jump in on your thread but I think im in the same sorta position as you.

I assume these are the holes in the frame/headstock your talking about

Image

and these are the small pipes from the airbox that dont reach

Image

and this is everything in place with the gap showing

Image

Ive also wondered about these not reaching, however until summer and good weather comes ramair may just prove a faster way to fill my airfilter with crap off the roads :x

Re: cbr400 NC23 ram air..........

Posted: Thu Jan 28, 2010 5:34 pm
by GooS3
Im wondering what will happen if you just made a scoop and attach it via pipes to that short pipes from the airbox.
I know that it wont make a difference at low speed but what will happen when lots of air get forced down the scoop @ higher speeds, into the airbox. Can the carbs even handle the extra pressure (if their is any).

cheers guys

Re: cbr400 NC23 ram air..........

Posted: Thu Jan 28, 2010 10:10 pm
by Cammo
GooS3 wrote:Im wondering what will happen if you just made a scoop and attach it via pipes to that short pipes from the airbox.
I know that it wont make a difference at low speed but what will happen when lots of air get forced down the scoop @ higher speeds, into the airbox. Can the carbs even handle the extra pressure (if their is any).
They won't be able to handle a pressure increase without modification, it will throw the fuelling way out.

You'll need to modify them so the float bowls are pressurised as is usual in race ramair setups.

Re: cbr400 NC23 ram air..........

Posted: Thu Jan 28, 2010 10:26 pm
by jac_is_smiling
DataRacer wrote: You'll need to modify them so the float bowls are pressurised as is usual in race ramair setups.
I was looking at pics on BDK Eng site earlier, I assume thats the reason the carbs, not just inlets, sit within the ramair box then. So everything is pressurised.

As an alternative, would it be possible to instead supply the float bowls with +ve pressure via the breather/overflow pipes from the carbs. i.e. connect them up to ramair box?

Re: cbr400 NC23 ram air..........

Posted: Sat Jan 30, 2010 6:46 pm
by bourney
Jack_is_smiling thats excatly my problem aswell mate.

So, where can we get the pipes from?


Whats all this talk about having to modify stuff to get the ram air to work :S surely if it's fitted from factory no modification is needed?????

Re: cbr400 NC23 ram air..........

Posted: Sat Jan 30, 2010 8:53 pm
by wonderbot
The system isn't really a ram air system because as far as I am aware the air ducts that run from the fairing and into the frame are not supposed to connect directly to the air box...they are just there to direct colder denser air into the space between the fuel tank and air box...I may be wrong but I'm sure this is what GF told me when I was collecting some bits from him.

Re: cbr400 NC23 ram air..........

Posted: Sat Jan 30, 2010 10:23 pm
by bourney
wonderbot wrote:The system isn't really a ram air system because as far as I am aware the air ducts that run from the fairing and into the frame are not supposed to connect directly to the air box...they are just there to direct colder denser air into the space between the fuel tank and air box...I may be wrong but I'm sure this is what GF told me when I was collecting some bits from him.
Right, now that actually makes alot of sense.

Denser air is more compact so you could fit more in the cylinder, increasing overall effiency.



So thats how it is supposed to be? The pipes arn't actually meant to connect to the frame?

Re: cbr400 NC23 ram air..........

Posted: Sun Jan 31, 2010 10:51 pm
by jac_is_smiling
aaahhh, fair enuf
that means im only missing the rubber heat shield bit that sits on top of the cam cover, last nc23 had one, this one doesnt,
not chasing horses just now, but will need one for summer lol