Effect of Ram Air Induction on Carbs?

So for my first project at uni I will be creating a new air intake system for a Yamaha YZF R1 98-99 bike.

This is the standard box:


This is a rough CAD model of the idea in my mind:



Now, being as I know absolutely F*cK all this stage, I have to research every bit of info I can. It seems that anything that appears relatively simple on a motorbike, actually isn't. And every topic seems to be an all out bat **** overboard brain melting mess.

My original thought was that a new intake would be easy as pie and all I'd have to do is stick some pipes on the air box and bolt it on the bike... But no!

So now I'm concerning myself with the carburettor's.

What I think I've figured out so far is that the carbs will need re-jetting and fitting a flo-commander.

Can someone give me a heads up on anything I may have missed or got completely wrong?

N.B... I am aware that a modification of this type may only result in a power increase in the top end and possibly flat spots in the low and mid range. This is for a track bike.

Cheers.

You're correct.
If you adjust the air intake, you'll need to adjust the fuel as well to maintain the fuel/air balanace.
This mixture takes place in the carb and would need to be perfected by dyno runs and jet/needle swaps - fail to get this right and the bike will run either lean or rich depending on which (air or fuel) you deprive it mostly of.
NB: IT WILL RUN< IT JUST WONT RUN WELL (as well as it otherwise could).

if you ensure the flow rate through your new airbox is the same as the standard then you wont have a problem... but that does sort of over write of the benifit of the project some what. All the best and keep us updated.

You will not be able to test RAMair on a dyno unless there is a posh one which can point 70mph wind into the box.

Most tuners try and compensate by running rich at the top end but only riding it will tell if its correct

[andrewsmith]

Originally Posted by Owenski

You're correct.
If you adjust the air intake, you'll need to adjust the fuel as well to maintain the fuel/air balanace.
This mixture takes place in the carb and would need to be perfected by dyno runs and jet/needle swaps - fail to get this right and the bike will run either lean or rich depending on which (air or fuel) you deprive it mostly of.
NB: IT WILL RUN< IT JUST WONT RUN WELL (as well as it otherwise could).

if you ensure the flow rate through your new airbox is the same as the standard then you wont have a problem... but that does sort of over write of the benifit of the project some what. All the best and keep us updated.

This

It maybe worth trying to get hold of a Kawasaki airbox and see how its done on a ZX10 or ZZR14. The SRAD's and TL also ran ram air systems.

Its worth bearing in mind Ram air is only effective above a certain speed (Going totally Banzai on a Airfield long enough to reach near top speed), it will be difficult to measure the BHP gain on a Dyno (unless its in a wind tunnel)

Edit: Beaten by Harry

I'm gonna test the flow rate of the box on a flow bench... Haven't really got access to a dyno but the guy I'm making the box for might. I think the flo-commander might be the way forward though...

http://www.flo-commander.com/

Maybe I have seen too many smoke and mirror "improvement" mods but I'd take the flo commander claims with a pinch of salt.

One of the most successfull RAMair mods was the ZXR400 RAMair which was developed by Kawasaki for racing and copied by everyone else, you may want to look at one of those as an example of how to do RAMair on a carb bike which didnt come with RAMair out of the box

Is that the bike that had what looked like pipes from the back of the washing machine going into the tank area?

Thats the bike but the "pipes" are not RAMair, if you look at most ZXR400 race bikes you will see the radiator dropped down and a mouth that goes intoa RAMair box which replaces the standard airbox

http://www.bdkraceeng.co.uk/Ram-Air%20Systems.html

[andrewsmith]

Originally Posted by hardhat_harry

Thats the bike but the "pipes" are not RAMair, if you look at most ZXR400 race bikes you will see the radiator dropped down and a mouth that goes intoa RAMair box which replaces the standard airbox

http://www.bdkraceeng.co.uk/Ram-Air%20Systems.html

Ooh Shiny carbon bits!!!!

They stole my idea... apart from the fact they did it first of course. I was going to try and relocate the rad of the R1 and use the same principle... So what are the pipes on that 400 above for then?