Custom Fighters - Custom Streetfighter Motorcycle Forum banner
1 - 17 of 17 Posts

·
jamal avatar #1
Joined
·
3,443 Posts
Discussion Starter · #1 ·
so i come from oil boilers. this whole water cooled ram air thing is really rustling my jimmies.

so i tried to build a ram air system because my bike was running like bollocks ( i used the existing kleen air crap, basically just stuck a 5/8 tube from the front mid) this obliviously didn't work and my bike now doesn't go past 3000 rpm.

I am now going to try this

i drilled 5/8 holes into my airbox now just waiting to go to the store to get some more hose


anyone have any experience with this? any other ram air mods? Ideally I want to have functioning ram air but at this point an easy delete would work also.

i also bought the ram air scoops but i really don't want to install them.
 

·
hate us cuz they ainus
Joined
·
1,827 Posts
I feel your pain. My old zx11 was super sensitive to where those two pitot tubes are actually sitting in tha ram air tubes. I tell you though, I never got the 11 to run right before I sold and the person that has it now is having problems too.
 

·
Premium Member
Joined
·
1,336 Posts
On the ZX I just sold I drilled one ogle through the bottom of the airbox, cut a small hole in the air filter, and fed the hose up through it. The carb bowls were seeing the same static pressure as what was coming into the carb inlets. I had to shim the needles slightly, but it pulled clean and hard all the way through redline.


Sent from Motorcycle.com Free App
 

·
Senior Member
Joined
·
890 Posts
On the ZX I just sold I drilled one ogle through the bottom of the airbox, cut a small hole in the air filter, and fed the hose up through it. The carb bowls were seeing the same static pressure as what was coming into the carb inlets. I had to shim the needles slightly, but it pulled clean and hard all the way through redline.


Sent from Motorcycle.com Free App
That's pretty much it - you need the carb vent tube to see the same pressure as the air box.
 

·
hate us cuz they ainus
Joined
·
1,827 Posts
Yes,yes easier said then done. For whatever reason it just doesnt work that easy sometimes. I tried every possible cobination of pitot tube placement. I even put them atw at the bottom of the box through the crank breather hole still no good.

QS, talk to neverenough. He has gotten the 11 to rev further then 3k I think
 

·
Yut-Ughhh
Joined
·
1,651 Posts
Hey yup, I've been tackling this issue for a little while now- I hopefully have it done on the ZX11 now.
I've done float adjustments, needle work, main jets, and pilot jets....seems these things seem to change from bike to bike as for what needs done lol
---BUT, everything I have read up on tells me that when you do this float bowl mod, it then allows you to properly jet the carbsp- which woohoo that'll be nice,
--- and that also when doing this mod it automatically makes the bike RIDICULOUSLY rich.



---------
I got mine to idle and rev perfectly in neutral.... right now the problem is when it is underload at low rpm that it is flooding out- but if I keep the rpms high it has no problems and pulls like a freight train.
 

·
Yut-Ughhh
Joined
·
1,651 Posts
Oh and as for not revving past 3k.... I would also DEFINITELY check your fuel pump, that's usually the magic number/rpm for when a fuel pump isn't working.
 

·
Ridin Dirty
Joined
·
377 Posts
The ram air on these kwaks were not designed to use pressurized air ramming through the inlets, but rather to make the intake charge more efficient..they put weep holes here and there to actually bleed off any pressurized air. Forget that the bowl equalizer tube needs to be "Equal" it actually always has to experience some sort of suction. On my zx-6, I put a crankcase filter on the motor, so I could plug the equalizer tubes to where the crankcase hose used to go on the airbox. Now, this was a fairly large hose, which is good because, the hose will have more suction if diameter is larger. I stepped hose size down to the size of the eq tube, then I tapped-threaded a plastic t-fitting so I could screw in a bolt to the t-fitting effectively creating an adjustable shut off in-line adjuster to regulate the amount of air flowing. it turned out that it liked to be barely open for the bike to run best.
If you decide to use ram-tubes, you will need to do high speed test and adjust that t-fitting the as the fuel bowls will not tolerate any positive pressure.
 

·
jamal avatar #1
Joined
·
3,443 Posts
Discussion Starter · #9 ·
i did the mod, did some self tweaking. bikes pulling good but has some flat spots. above 7k. fine tuning stages now.



going to buy another airbox also and try the vertical placement if i can't get this straightened out.
 

·
Senior Member
Joined
·
890 Posts
The ram air on these kwaks were not designed to use pressurized air ramming through the inlets, but rather to make the intake charge more efficient..they put weep holes here and there to actually bleed off any pressurized air. Forget that the bowl equalizer tube needs to be "Equal" it actually always has to experience some sort of suction. On my zx-6, I put a crankcase filter on the motor, so I could plug the equalizer tubes to where the crankcase hose used to go on the airbox. Now, this was a fairly large hose, which is good because, the hose will have more suction if diameter is larger. I stepped hose size down to the size of the eq tube, then I tapped-threaded a plastic t-fitting so I could screw in a bolt to the t-fitting effectively creating an adjustable shut off in-line adjuster to regulate the amount of air flowing. it turned out that it liked to be barely open for the bike to run best.
If you decide to use ram-tubes, you will need to do high speed test and adjust that t-fitting the as the fuel bowls will not tolerate any positive pressure.
Can't say that was anything like my experience with my E1 zx9. I kept the ram tubes (albeit cut down) as below:


and I ran the carb balance tube to the bottom of the air box right near where the ram tubes entered it. I also put a T piece on the KLEEN intakes and connected that to the crankcase breather. Revved up a bit crisper (the theory is that it keeps the crankcase in a vacuum).

I ran the bike without those semi ram tubes and just had the balance pipe "disconnected" under the air box and the bike suffered a lot with cross winds and pretty much any scenario where the balance pipe was seeing a different pressure than what was happening in the air box.

The weep holes you are talking about are actually drain holes to let water out - they are not large enough to affect the ram air effect when the bike is at speed.

And by the way - the guy in the video above who says he's gained 15hp by doing his mods is full of shit.
 

·
Administrator
Joined
·
50,498 Posts
Can't say that was anything like my experience with my E1 zx9. I kept the ram tubes (albeit cut down) as below:



And by the way - the guy in the video above who says he's gained 15hp by doing his mods is full of shit.
LOL ;)

Rep fer you matey .
 

·
Ridin Dirty
Joined
·
377 Posts
Can't say that was anything like my experience with my E1 zx9. I kept the ram tubes (albeit cut down) as below:


and I ran the carb balance tube to the bottom of the air box right near where the ram tubes entered it. I also put a T piece on the KLEEN intakes and connected that to the crankcase breather. Revved up a bit crisper (the theory is that it keeps the crankcase in a vacuum).

I ran the bike without those semi ram tubes and just had the balance pipe "disconnected" under the air box and the bike suffered a lot with cross winds and pretty much any scenario where the balance pipe was seeing a different pressure than what was happening in the air box.

The weep holes you are talking about are actually drain holes to let water out - they are not large enough to affect the ram air effect when the bike is at speed.

And by the way - the guy in the video above who says he's gained 15hp by doing his mods is full of shit.


I ended up with ram inlets and sealed the airbox everywhere besides the water weeps.
I did A lot of testing on their design, even replicated the size, and shape of ram intake and placement of the balance tube intakes. I even made the balance inlet in and out adjustable so I could find a "boundary layer" where the inlets may prefer to be.
The factory carefully designed the inlet size and everything else, to where the intake charge would try to take air OUT of the balance tubes first, hence the vacuum.
If you blow on that balance pipe, the carbs will totally flood...
I even put a low pressure gauge to see how much air the ram system could pressurize.
any size hole even one weep, will NOT let the airbox experience above atmospheric pressure under 140 mph. When I sealed up the box airtight, I got up to 1/2 psi by 120 mph and the air will begin to "spill" out of the inlet, gaining no more psi. The adjustable vacuum allowed me to properly jet and tune the ram air system for the changes to the exhaust.
 

·
Registered
Joined
·
652 Posts
I ended up with ram inlets and sealed the airbox everywhere besides the water weeps.
I did A lot of testing on their design, even replicated the size, and shape of ram intake and placement of the balance tube intakes. I even made the balance inlet in and out adjustable so I could find a "boundary layer" where the inlets may prefer to be.
The factory carefully designed the inlet size and everything else, to where the intake charge would try to take air OUT of the balance tubes first, hence the vacuum.
If you blow on that balance pipe, the carbs will totally flood...
I even put a low pressure gauge to see how much air the ram system could pressurize.
any size hole even one weep, will NOT let the airbox experience above atmospheric pressure under 140 mph. When I sealed up the box airtight, I got up to 1/2 psi by 120 mph and the air will begin to "spill" out of the inlet, gaining no more psi. The adjustable vacuum allowed me to properly jet and tune the ram air system for the changes to the exhaust.
Ram air is never compressed it, it is as it says.
The Kawasaki systems never see positive pressure as you say (unless you're doing a mental speed with the throttle closed)
However, it does increase the CFM going in to the head. Anyhoo, enough scemantics.
The carb bowls need the same pressure as your airbox is under, or one atmosphere. There is countless documentation on the net on deleting the ram air systems, and if anyone says the bowl vent tube in the airbox (same as Hillsy did) does not work, they have done it incorrectly.
Another thing to watch out for is excessive bowl pressure with your fuel pump, without the air flow in to the bowl vent equalising it you may end up with a rich condition but that is pretty rare


Do the carb vent mod
 

·
jamal avatar #1
Joined
·
3,443 Posts
Discussion Starter · #15 ·
i did my own setup using a respirator mask as filters to keep dirt out. used 5/8th tubes into 3/8ths into a fuel line extenders. this setup works unlike the the previous one i built.

ill post some pics tuesday with a further elaboration of what i did. I'm very pleased with the results. i'm also going to try the vent mod just for simple comparison to find the most efficient and best responding setup.
 

·
jamal avatar #1
Joined
·
3,443 Posts
Discussion Starter · #17 ·
bloody phone isn't linking up to computers. It does take a charge tho.

gotta dyno it for jetting now :shocker:
 
1 - 17 of 17 Posts
Top