Airkit question???

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By Racerxlilbro on Monday, July 22, 2002 - 09:28 am:  View Racerxlilbro's Profile Search for other posts by Racerxlilbro Edit this post

Would there be any advantage (in terms of Ram-Air) in sealing the base plate on the edges to the bottom of the tank?  

By Crmc33 on Monday, July 22, 2002 - 10:21 am:  View Crmc33's Profile Search for other posts by Crmc33 Edit this post

might stop some of the heat getting up there.

Wouldnt make as much noise tho! hehehehehe 

By Crmc33 on Monday, July 22, 2002 - 10:36 am:  View Crmc33's Profile Search for other posts by Crmc33 Edit this post

worth remembering too that unless youve sealed the gaping holes in the ramair tubes then there basically isnt any ram effect in the original airbox cos sufficient pressure cannot build up.  

By Racerxlilbro on Monday, July 22, 2002 - 11:00 am:  View Racerxlilbro's Profile Search for other posts by Racerxlilbro Edit this post

crmc33,

If that's true, then why make all the fuss over dyno with fans???

Here's what I'm wondering...since air, like water, electricity, etc., follows the path of least resistance, wouldn't air under pressure from the ram-air tubes spill over the gap around the base plate rather than go into the throttle body?  

By Jorgen on Monday, July 22, 2002 - 12:03 pm:  View Jorgen's Profile Search for other posts by Jorgen Edit this post

Racerxlilbro,

Don't forget that the engine needs (a lot) of air. Higher revs, more air. Think about it the other way around and assume that the only way any air can get into the airbox is through a tiny straw. That will of course not work because the engine will not get enough air, the hole is simply too small. I'm no mechanic and I don't know the true secrets about the airkit, but it's my understanding that you might face a similar situation on a dyno without fans, i.e. the engine tries to consume more air than it can get. If my theory is correct, then you wouldn't need a dyno with fans if you could remove the tank (!) while the bike was on the dyno.

// Jorgen  

By Racerxlilbro on Monday, July 22, 2002 - 02:13 pm:  View Racerxlilbro's Profile Search for other posts by Racerxlilbro Edit this post

Jorgen,

Hmmm. I don't think so. The idea of the ram/air is to simulate forced induction - i.e. positive pressure in the inlet tract v. vacuum in a "normal" situation. So, it's not just a matter of having the air "available." Right, Jorge?  

By Dangerous on Monday, July 22, 2002 - 02:47 pm:  View Dangerous's Profile Search for other posts by Dangerous Edit this post

HEY GUYS!

Forget your theories. Because here's the definative one:

IT WORKS. BELIEVE IT!

Try a bike that's had one fitted if you can, you WILL believe it then. This will shortly be followed by you placing an order for one.

Oh! before you get an Airkit, make sure you get down to the gym, because you are going to need all the forearm strength you can muster to hang on after it's fitted!

Dangerous 

By Myapriliarsv on Monday, July 22, 2002 - 04:19 pm:  View Myapriliarsv's Profile Search for other posts by Myapriliarsv Edit this post

Racer
This is only my theory and it could be off base so take it with a grain of salt. The idea behind the air kit is to get as much air as possible to the engine. Because the air kit is not sealed air enters from many different points and the engine uses all the air it can. I would think that sealing the ram air tubes may offer a little benefit, but not enough to really make a noticable difference....as it is now you get air for the tubes, and around the tank....i don't think the effort to seal the tubes with the air kit is worth it.

what may be a worthwhile move is for you to figure out how to enlarge those tubes you have. (Racer hasa California model which has extremely small intake tubes) You saw the other falco on display at Laguna and the Milles on display..they had intakes that were much much larger than yours...in my opinion I think yiou would benefit more there...

 

By Salkhan on Monday, July 22, 2002 - 07:57 pm:  View Salkhan's Profile Search for other posts by Salkhan Edit this post

Ram Air is shown to really only work at very high speeds (130-140+) and maybe give about 2-3 HP at BEST. And that has to be in a near-perfectly sealed system.

I'm not Haga yet, so I won't need that. I'll take the mid-range for now.  

By Crmc33 on Monday, July 22, 2002 - 11:01 pm:  View Crmc33's Profile Search for other posts by Crmc33 Edit this post

IMHO,
The OE intake tubes do not produce any ram effect. By this I mean supercharging.
The intake system does provide a reliable supply of cold air to the airbox. The problem is that the airbox chamber isnt big enough or doesnt flow enough to meet the demand of the engine hence the airkit works better and so does the SP/Evo style enlarged airbox.
A dyno needs large fans or small fans that run at high air speed to simulate road conditions of air flow in order to test the various intake/exhaust mods available.
Even the airkit needs a good flow of air otherwise the intake area will get saturated with hot air from the engine and hence reduce the compressive efficiency of the engine. Hence the airkit allows the intake to draw air from wherever it wants.... and the intake tubes are still important to supply fresh air at high speed (it should push the hot air out of the back of the bike).
I seam to remember someone sealing the intake tubes on the OE airbox and the bike making less power on a dyno. Maybe this shows that its further restricting the intake area for the engine OR the dyno wasnt satisfactorily simulating the air flow at high speed. Id guess maybe a bit of both.

Out of interest Racer, have your removed the under tank foam and raised the petrol tank?
I found this had a big positive effect. 

By Benw on Monday, July 22, 2002 - 11:04 pm:  View Benw's Profile Search for other posts by Benw Edit this post

A bike with carburation that is set up for ram air operation will obviously benefit. Take the ZX-6R for example. If you disconnect the ram air pipes in the front fairing, the bike will run at tickover but when you start moving it'll be extremely weak and will hardly run. The float bowls needs to be positively pressurised in order for them to work. This pretty much goes against what people are saying about it only working at very high mph.

As long as your engine is getting as much cool/dense air as it wants then it will be producing as much power as it can in that state of tune. These bikes aren't set up for ram air. If they were, they wouldn't run with the airkit once you'd pulled away. All you're trying to do is get cool air in the engine.

Try it. I don't think you'll get much benefit.

B  

By Befbever on Tuesday, July 23, 2002 - 07:27 am:  View Befbever's Profile Search for other posts by Befbever Edit this post


Another thing about ram air is that the bike will rarely run on a track the way it runs on a dyno. You've got the front moving up and down while accelerating and braking, the bike being at an angle in corners, etc. All these effect the ram air. Not like with an F1 car that basically just sits there. That's what Team Roberts are trying to do next: do dyno's with the bike moving as in real conditions.

But as far as the fan issue goes: anyone who thinks a modern bike like the Falco doesn't need big fans for a dyno run, try the following:

Take to the road, rev the bike to the limiter in 5th gear sitting behind the bubble. Now sit up straight or put your arm out. What happens? Feel some wind resistance? Think about this and wonder how accurate a dyno run is with only a fan to cool the radiator.

And Racerx, you best browse through some posts about the air kit to get your answer about the sealing of the bottom. Scroll down to 4/5ths of this page. Your question means you haven't been paying attention.
 

By Racerxlilbro on Tuesday, July 23, 2002 - 09:45 am:  View Racerxlilbro's Profile Search for other posts by Racerxlilbro Edit this post

GRRRRR!

Was too! Was too! It was a different question Mayo Man!

Anyway, Crmc33's idea about raising the tank as well as removing the foam is an interesting one.

BTW, I've already GOT the airkit, and YES, it is amazing. I'm just asking theoretical questions... 

By Crmc33 on Tuesday, July 23, 2002 - 12:19 pm:  View Crmc33's Profile Search for other posts by Crmc33 Edit this post

The tank raising idea wasnt mine as its been done by other owners too. It was also done may moons ago on RC30's and TRX850s to improve power and carburation.

I also raised the tank as it gives me a better shelf to rest my gut on 

By Powermaster on Thursday, July 25, 2002 - 02:44 am:  View Powermaster's Profile Search for other posts by Powermaster Edit this post

CRM's answer is perfect, there isn't much I can add, do not try to seal anything, one must remember that I have done that already,lifting the tank has always proved better power, again no seal. So far lots have been done to the airbox but from where I am standing no one has come up with better figures. , oh and BTW, forget shorter trumpets, it doesn't work.  

By Crmc33 on Thursday, July 25, 2002 - 03:02 am:  View Crmc33's Profile Search for other posts by Crmc33 Edit this post

yeh, forget the trumpets but not the crumpet 

By Salkhan on Thursday, July 25, 2002 - 06:08 am:  View Salkhan's Profile Search for other posts by Salkhan Edit this post

Shorter Trumpets sounds like a personal problem honestly.  

By Racerxlilbro on Thursday, July 25, 2002 - 10:35 am:  View Racerxlilbro's Profile Search for other posts by Racerxlilbro Edit this post

Short trumpets...hmmm, I think they make a pill for that, right? 


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