here i go again!!

[Jethro]

Glad I got outta this one early!

[Anonymous]

air box

Your dead right Earl, but heck let nert take his airbox of and prove it to him self, valves aren,t that expensive, things are a compromise for a good bike, and abike that makes it in the sound department, is nice to the ear, my blke is at about 89db, pull the air box off and it will jump to about, 93db at mid throttle, epa stamp on mufflers say bike stock EPA noise limit should be 87db

[earlfor]

Chickensh ittt. LMAO :-) :-) :-) :-)

Earl

Glad I got outta this one early!

[earlfor]

Re: air box

Yep, I can carry on a normal conversation while standing beside my running 1150. I like it that way. :-) Its quiet and its not all that slow either. :-)

Earl

Your dead right Earl, but heck let nert take his airbox of and prove it to him self, valves aren,t that expensive, things are a compromise for a good bike, and abike that makes it in the sound department, is nice to the ear, my blke is at about 89db, pull the air box off and it will jump to about, 93db at mid throttle, epa stamp on mufflers say bike stock EPA noise limit should be 87db

[nert]

My intention was NOT horsepower, nor was it "sound". I have not yet heard a reasonable answer as to why some claim their engines won't even idle if they have an air box leak. I guess if you can deny science and the facts, and britanica definitions, you can justify your claims.

I guess i will take a nice long ride on my GS into the sunset....unless of course you believe i will fall off the end of the earth.

[Jethro]

I guess i will take a nice long ride on my GS into the sunset....unless of course you believe i will fall off the end of the earth.

I can say by experience that my bike idles just fine without the air box or filter installed. I don't understand that either Nert.

[QuaiChangKane]

Nert - you've got waaaaay too much time on your hands. There have been plenty of explanations as to why air box leaks can cause your bike to run poorly, but we've gotten caught up in the symantics of carburetion.

I am sorry, science says you are incorrect. There is not greater pressure in the bottle than there is in the atmosphere either as you stat!!!

But there is greater pressure in the pop bottle - that's what the bottle is for. Take into account the weight of the liquid pushing on the walls of the bottle. The liquid wants to find its point of equilibrium with gravity, but the bottle prevents that - so the liquid pushes on the walls of the bottle and the bottle pushes back until they achieve stasis. Don't forget about the effect of gravity and mass on pressure.

Defining siphoning as only working through an "n" shaped tube is simple naivite - that example is only for gravity siphoning. There is mechanical siphoning as well, examples being bilge pumps, windmills, and carburetors.


The difference between pushing and pulling fluids is thus:


A distillery pushes fluid by creating a pressure differential through the use of heat. All things being at a stasis, mass will not move without application of energy. In this example, the energy is being applied at the source of the liquid (heat) to move the liquid to the other end of the still. Heat increases pressure at one end, pushing the liquid to the area of lower pressure at the other end.

A siphon or (vacuum pump)does just the opposite. Energy is applied at the destination instead of the source, creating an area of lower pressure which pulls the liquid to its destination.

It's all about where the energy is applied to the apparatus - you pull a shopping cart from the front, or push it from the rear. While you're touting scientific constants (none of which are being argued here, I assure you), don't forget about the fine points of the English language.


And finally, I'll leave you with the scientific evidence you crave.....


Google "Stoichiometric Ratio".



-Q!

[QuaiChangKane]

My intention was NOT horsepower, nor was it "sound". I have not yet heard a reasonable answer as to why some claim their engines won't even idle if they have an air box leak. I guess if you can deny science and the facts, and britanica definitions, you can justify your claims.

I guess i will take a nice long ride on my GS into the sunset....unless of course you believe i will fall off the end of the earth.

A bike whose mixture is already lean (as these bikes all were from the factory for emissions reasons) will idle poorly (if at all) with no airbox.


Mine, on the other hand, runs well with no air filter because it's jetted too richly.

[earlfor]

It isnt a claim. I dont need an encyclopedia to tell me that a lean running engine can burn valves. :-)

Hope you enjoy your walk back. :-)

Earl

I guess if you can deny science and the facts, and britanica definitions, you can justify your claims.

I guess i will take a nice long ride on my GS into the sunset....unless of course you believe i will fall off the end of the earth.

[KEITH KRAUSE]

Glad I got outta this one early!

Glad I never got into it, period!!
I can simplify things:
CV carbs run bad with air box leaks.
VM carbs run OK, but leaner.

[Anonymous]

SCIENCE BEHIND FLUID FLOW...

Q and Nert

You are talking science - so look up these two principles

PV = nRT

and Bernoulli's Principle. (Like the perfume atomizer of victorian era)

I am not saying you are wrong. But look up these principles.

For a given mass volume of air....if squeezed into a smaller opening - air pressure will DROP and air velocity will SPEED up.

So what.

Bernoulli's Principle is what basically causes fuel to be pulled up from the carburator float bowls.

Basically, opening up the INLET of an air box (part going to the air outside) will LEAN out a bike. Why? Air boxes are restrictive or "tight". Tight means that the air box is the most restrictive part of the intake tract into the bike's engine. Remember the air box feeds multiple carburators, and at high RPM's all of the carburators are flowing their max CFM or cubic feet per minute. The INLET opening of the airbox must be able to feed 4 carburators.

Sound is (yes) why airboxes are restrictive. Another way to quiet a bike is to make the airbox volume larger.

Did you know if you make a given air box volume larger, that you may have to rejet for lean condition? Guess what...the same works for EXHAUSTS. If you make the volume of the exhaust canister larger but do not change the tailpipe opening, the bike may lean out also?. This is because the RESERVOIR of air, either in the canister or the airbox, is larger, and remember air is COMPRESSIBLE, so a larger volume is able to Absorp PEAK pressure pulses better, so the engine "thinks" the airbox or canister is LESS RESTRICTIVE.

How do I know - engineer - how else - I played with airboxes and exhaust canisters.

LASTLY - have we covered all we need to know about fluid flow and air boxes? HECK NO.

Brain Teaser: Is the volume of an air box the only thing important to affect tuning of the intake SYSTEM? Answer - NO. Intake tuning is COMPLEX stuff - not totally understood.

EARL/Q/Nert: Take a plastic liter soda bottle - fill it halfway with water and blow across the opening. You'll hear a certain pitch sound. Empty the water out, the pitch will go DOWN. Right? Larger volume, lower pitch. NOW, take the empty plastic bottle and squeeze the center of the bottle flat (pinch it in the middle). Now blow across the bottle again. What happened, the sound will get LOWER for a DECREASED VOLUME of the bottle. How can that be? Who knows the answer?

And so, airbox SHAPE, VOLUME, inlet and outlet opening sizes, shape of the inlets and outlets ALL affect air flow - otherwise known as INTAKE TUNING... TUNING and it's RESONANCE affect the ability of an intake system to flow.

Basically - that is why we just open up the air box some and rejet. The science will drive you mad. - Tony Dieter

[nabrams]

I believe the answer to Tony's bottle-question is that the effective volume and shape of the bottle will affect the interference pattern of the reverberating sound waves - this in turn will affect the pressure and frequency of the sound wave exiting at the mouth of the bottle (sound is just a pressure wave).
If I'm correct, then this is perfectly analogous to the airbox. And of course any leaks would affect the exit pressure (pressure going to the carbs).

[Craig]

If you get enough pop bottles and squeeze them all differently, and get 20 guys to blow on them, you will be able to play Jingle Bells!!! Try and do that with a carb and airbox!!! Merry Christmas to all, and to all...I hope this thread will end soon

Kind regards...Craig

ps. Merry Christmas

[Anonymous]

pop bottles

Just giving notice that I will NOT be at the pop bottle blowing fest!!!!

[earlfor]

Awww, not a big deal. It isnt any fun when everyone agrees all the time. :-)
Besides, no one was rushed to the O.R. with terminal consternation as a result of the discussion.

Earl heh heh

..I hope this thread will end soon