Has anyone ever deleted the zx11 airbox? : Kawasaki ZX Forums: Kawasaki Ninja Forum

Cwiseguy · 11-11-2009, 01:07 PM

Just looking to see if anyone has ever successfully deleted the zx11 pressurized airbox successfully?

Thanks, Cwiseguy

2 - 1990 zx11's
1981 Gpz1100
'73 and '73 z1 900

TwistedKestrel · 11-12-2009, 07:03 AM

I don't think it would be that hard, the only problem would be putting pod filters on the carbs because the intakes are on an upward angle. As far as the pressure tubes for the diaphragms are concerned, you'd only have to block them off I think.

However, you are definitely going to suffer a loss in performance.

Cwiseguy · 11-16-2009, 05:23 PM

The airbox is such a pain in the @$# to fool with if you like to take your carbs off a lot and are always tinkering with the performance as with jets and the like...

Even changing spark plugs is a pain. It would be nice to just take the box off and replace it with something. When racers buy these zx11 motor and use them on sprint cars they don't have the airbox on them, they have stacks and pods. I would think that the performance would not be an issue as it is not with the sprint car racers.

Thanks, Just a thought...

Hammerhead · 11-16-2009, 06:01 PM

Sprint cars probably don't exceed 120 mph which is where frontal air pressure helps increase horsepower by pressurizing the airbox. If you never plan to go any faster than that, you don't need the airbox. Anywhere faster than that, the same bike with an airbox will suck the paint off one with pods as it goes past. Also the volume and intake cross-section of the airbox is engineered to give maximum sonic effect which is volume x speed of sound to time positive pressure waves to hit the intake valve head as it opens to ram more charge into the combustion chamber.

rnoliver · 11-16-2009, 06:44 PM

Here is one good way to get rid of the airbox......

I need to get some pictures with the wiring harness cleaned up and everything as it is now, but you get the idea.

ejmesq · 11-17-2009, 09:57 PM

[quote=Cwiseguy;214208]Just looking to see if anyone has ever successfully deleted the zx11 pressurized airbox successfully?

Suggestion: If you haven't already done this, warm your bike up and take it though redline line to the top of sixth gear.

rnoliver · 11-18-2009, 07:45 PM

[quote=ejmesq;216009]

Quote:

Originally Posted by Cwiseguy

Just looking to see if anyone has ever successfully deleted the zx11 pressurized airbox successfully?

Suggestion: If you haven't already done this, warm your bike up and take it though redline line to the top of sixth gear.

ejmesq · 11-19-2009, 04:09 PM

[quote=rnoliver;216277]

Quote:

Originally Posted by ejmesq

yipes. . .the dreaded headscratch. The 11 is a torque monster. Outside of 15-30 MPH twisties, it can stay up wiht everything but a better rider on superior suspension, I'm not knocking the airbox question, but why castrate the engine by pulling the ram-air box.

EBC/Galfer brakes, Mr. Turbo pan-mod, Corbin seat, the Mich 2Cts are excellent mods.

The next upgrade is probably a Zx-10 for handling or a ZX-14 as a galactic sport tourer.

Hammerhead · 11-19-2009, 05:05 PM

One of the most coveted and closely held secrets in the MotoGP paddock is the size and configuration of everyone's airbox. If these guys have airboxes, what is the logic for eliminating them? Mine comes off everytime the valves are checked and although it's a few nuts and bolts, it's in no way a major pain to remove. Gives me the opportunity to clean the filter and blow out the bugs that got sucked up on triple-digit runs.

Hammerhead · 11-19-2009, 05:07 PM

Quote:

Originally Posted by rnoliver

Here is one good way to get rid of the airbox......

Isn't that an airbox on the end of the blower tube? (Don't say it's a plenum, that's a synonym for airbox)

ejmesq · 11-19-2009, 05:21 PM

Quote:

Originally Posted by rnoliver

Here is one good way to get rid of the airbox......

I need to get some pictures with the wiring harness cleaned up and everything as it is now, but you get the idea.

Did this box improve performance?

rnoliver · 11-19-2009, 05:32 PM

^^

I meant to say STOCK airbox!

rnoliver · 11-19-2009, 05:57 PM

Dang, had a second reply all written and my internet connection went away (stupid hotel internet) so now I have to re-write it.

Ejmesq, sorry, missed the second post before I made the last reply. The plenum (I always thought the difference was that airboxes had filters, or were meant to) actually really hurts performance if you don't have the turbocharger hanging out up front. If you count that though, then you get a reall kick in the pants.

If I hadn't turbocharged my 11, I would never have considered removing the stock airbox. I did not find it to be such a hassle to remove, although my bike was pretty well dialed in so I wasn't messing with the carbs on a daily basis.

The headscratch was just to get you to clarify the run to redline suggestion. Although, finding many places to top out 6th gear can be challenging!

Cwiseguy · 11-19-2009, 09:30 PM

Cwiseguy...

jay jay · 11-21-2009, 12:00 AM

takin the air box off any bike is not a big deal in testing in riding conditions its gets tricky but it is possible i run sometimes with out it u just have to come up with a way to get same air or close to it commin in and as i seen in pics an after market car kit will do if it does around same volume or more of air i know what i said sounds stupid to the few that know what is goin on but im doin my best to past on the education im payin for

rsr · 11-21-2009, 10:58 PM

Quote:

Originally Posted by jay jay

takin the air box off any bike is not a big deal in testing in riding conditions its gets tricky but it is possible i run sometimes with out it u just have to come up with a way to get same air or close to it commin in and as i seen in pics an after market car kit will do if it does around same volume or more of air i know what i said sounds stupid to the few that know what is goin on but im doin my best to past on the education im payin for

On a "D" you can do that and retain the velocity stacks and the plastic frame
that bolts to the carbs, on a "C" such as he has it all one piece

ejmesq · 11-22-2009, 09:24 AM

Quote:

Originally Posted by rnoliver

< snip...If I hadn't turbocharged my 11 ...snip>

I'm not trying to hi-jack this thread, but have you posted on the the turbo charger yet?

rnoliver · 11-22-2009, 11:40 AM

Had a clearance issue on the turbine side causing it to bind when it got hot. Recieved the repaired turbocharger back last Monday, but I won't be home to instal it until Thanksgiving. Wanted to post about the whole process once it was done, but that is taking soooooo long it's driving me crazy. I should get a post up the week after Thanksgiving, taking a couple of extra days off from work.

To put it back on topic, kind of, I'll have a complete D model airbox assembly, K&N filter, ram air tubes, etc. if anyone is interested...

zx11_dragon · 11-24-2009, 10:41 AM

this thread is interesting. cus i was wondering the same thing. my old airbox has been removed so many times that half the bolts are missing and non of the tubes line up, and on the "C" everything needs to be all sealed up. sorry to throw another question in here but, can the carb and airbox from a "D" fit onto a "C"?

rnoliver · 11-24-2009, 08:04 PM

Quote:

Originally Posted by zx11_dragon

sorry to throw another question in here but, can the carb and airbox from a "D" fit onto a "C"?

Unfortunately, no, they are quite different. I think you can still get most of the C parts at pretty good prices from BikeBandit, or other web sites like that. But that is for new, which might be worth it over 15 yr. used on ebay.