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Discussion Starter #1 (Edited)
This is much quicker than the hour or so some have reported for sawing the box into pieces to remove it.

The key to removing the airbox in one piece is unplugging the wiring harness and pulling the harness out of the frame. This makes just enough free space for the box to move up in the frame and clear the front head. With a few more steps you can then wiggle box out of it's nest.

1) Remove the usual intake plumbing for carb removal, including the two oval tubes at the front of the airbox connecting to the ears.

2) Remove the crankcase vent hose at the lower left front of the airbox. You can remove the smaller drain hose off the lower front right but I was able to leave it on the box, just un-clipped it from the frame.

3a) Remove the one bolt holding the bracket for the six wiring plugs beside the front ignition coil so it's free to move upward. 3b) Pull right front plug and move it to the left side.

4) Remove one bolt holding the coolant tube on the rear head, wiggle it out of the head carefully, it has an o-ring. Also removed the thermostat and hoses.

5) Remove the air injection hoses from the engine and airbox, one vacuum line from the rear carb, then pull the valve and hoses out together. I'm doing coasters so this isn't going back on. Perfect time to do coasters!

6) Unplug the wiring harness at the rear, battery box, rear ignition coil, etc. Unlock the headlight trigger wire and pull it from it's plug, this wire stays with the stator wires. It's impossible to reconnect the harness wrong unless you really try. Wires on bullet connectors are color coded and plugs only fit in one spot. The only two to remember are on the rear coil, grey on bottom, red on top. Remove the harness straps as you go, then pull the harness out of the frame. I left the relay connected to the harness since it was dangling free.

7) With the right hand, lift the front of the airbox and slide it back until it hits the frame tab at the rear. With the left hand, lift the rear up, flexing the tank slightly, while applying rearward pressure with the right hand at the wishbone of the frame. I just wrapped my hand around the frame used my fingertips to push back. Wiggle the rear of tank with rearward pressure from the front and the airbox pops right out.

I kept the airbox intact in case I don't earshave, but had no idea it would be so quick or easy. With all the free space, I can't imagine not earshaving now. And with all that junk off the top of the engine, it may just run a bit cooler, besides making carb work easier.

This is really only adding 2 or 3 steps to the airbox removal process, the harness, rear head coolant tube, and the front electrical bracket. I have little doubt I can reconnect the harness in five minutes. Just a bit of extra work, but we know our bikes are put together like clocks, or nuclear subs, anyway.

Did this from memory, so if anyone sees a mistake, feel free to point it out and I'll correct.
 

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Chasin' the blacktop
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Sounds a lot easier than fighting with a sawzall cutting up the airbox. Great post!
 

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Just a regular guy
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Well, I just did the ear shave and while cutting out the airbox wasn't fun... it only took me about 15 minutes using a flexible saw blade with tape wrapped over one end.

I'm sure this way works... but for me it seems mire cumbersome. But to each their own and heck, nothing wrong with having another option.
 

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Discussion Starter #4
Sounds a lot easier than fighting with a sawzall cutting up the airbox. Great post!
Thank you.

...
I'm sure this way works... but for me it seems mire cumbersome. ...
It looks like a lot in print, but it really took a lot longer to lay out the post than to do the work.

In my situation, coasters and a stator job, it just added a few minutes.
 

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Thanks Spockster.

I was wanting to keep my air box intact when I did my ear shave on the off chance I ever decided to go back and reverse it.
 

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Discussion Starter #6
You're welcome Ndr.

Made an edit at - 3b) Move right front plug wire to left side.
 

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Discussion Starter #8
Didn't think of that. But I'd hate to break the gasket and have to buy that right now. The warden says this project is getting out of hand :p , but doesn't understand the joys of riding.
 

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Thanks Spockster.

I was wanting to keep my air box intact when I did my ear shave on the off chance I ever decided to go back and reverse it.
^^ My thoughts exactly.

I haven't decided if I even want to do it yet.

Thanks for the write-up Spockster
 

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Discussion Starter #11
eusjma, you're welcome and thanks. Thinking the write-up might look better just posting the high spots, the two or three added steps.

Found a pic of the valve cover gasket, it does look pretty substantial. Is it metal reinforced?
 

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Jack of all trades
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Nope, just a plain ol' rubber gasket. Don't just rip the valve cover off and it is pretty easy to keep it stationary. Peel the gasket from the valve cover carefully and you don't worry about messing it up.
 

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Discussion Starter #13
Good to know, thanks.

Hard to believe the design of the intake, pulling through those 1" square holes. For a while I thought the chrome ear covers were open. Really surprised me.
 

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Excellent idea. I would recommend soaking the airbox in WD-40 first, to help make it come out easier, and to help prevent gouging it. If I ever needed to remove mine, I would definitely want to put it back in.

Those little square holes are there to restrict air flow, to keep the air/fuel mixture right. I did remove the rubber grommets from mine (still have them) it made no difference.
 

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Discussion Starter #15
For what it's worth....

Plugged the harness back in last night. It was super easy, no head scratching about where this or that plug went, everything has it's own shape and color so there's no confusion.

I'm relocating the stator and pickup coil wire harnesses to run over the top of trans. In the factory setup, these wires get twisted, kinked, clamped, and crammed between the stator cover and trans., and clamped by a bolt behind the clutch lever. The rubber cover on my original stator lead was cut open by the clamp and was also rubbing the clutch lever.

Over toward the top/middle of the trans, there's a loop sticking out of the case, may be a lifting eye for use at factory assembly. I plan to try and use this empty loop to bolt up something to hold the two harnesses and suspend them above the trans, this should be a cooler environment for them.

Might not be as clean and pretty as the factory setup, but it should allow the stator wires to run cooler. My thinking... engine heat warms the wires as heat from the electric current is also heating them. So less engine heat has to be good.

I can always cover the relocated harnesses with a black or chrome wire loom/cover, just need about 12".
 

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Good to know, thanks.

Hard to believe the design of the intake, pulling through those 1" square holes. For a while I thought the chrome ear covers were open. Really surprised me.
The one inch square holes are what control the amount of intake air to the engine, just like the snorkel did on the air cleaner of old carbureted car engines. Back then, many people flipped the dished top of the air cleaner lid upside down, creating a gap between the lid and the pan, so air could get in all the way around. But I don't suppose that many realized that increased air flow meant a leaner A/F mixture, and that you would need to rejet to compensate for it. Then came those cheap chrome aftermarket air cleaners, with just a thin top and bottom plate, which left the filter element open all the way around. Since those still use the stock filter, they work fine, but you do need to rejet for them, at least on carbureted engines.

I still have my carbs off, awaiting parts. I am still considering using the Uni filters. But here is something I found out. The manual says to remove a whole bunch of cooling system parts in order to make it possible to raise the airbox high enough to get the carbs in and out. I can get the carbs out without doing that, and I can get them back in, but I cannot get the rubber ducts back in place in the surge tank. Last time I put the carbs back in I found a way. I cut a bunch of rubber off the top part of the ducts, which stuck way up inside the surge tank, above the groove which holds the ducts in place. This rubber was very thick, and made the end of the duct very stiff, which is why it wouldn't go back in with the carbs in place. Cutting it off made the ducts much more flexible, and they popped right in. Since room was very tight, I used the sanded down end of a 1/4" wood dowel to finish pushing the duct into place. Don't even think about using a screwdriver unless you want a hole in the duct. I thought they might pop out because they were much more flexible, but they never did.
 

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The one inch square holes are what control the amount of intake air to the engine, just like the snorkel did on the air cleaner of old carbureted car engines.
This is where we part company. 2 sq in is 50% more area than a carburetor that only draws for 284* out of every 720*. It only draws hard for about 90*, I would guess the amount of air to be much less than the plenum volume.

The small snorkels (mostly 2 bbl carbs) were several times more area than the throttle area.

Putting open element air cleaners on, often went slower at the strip mostly because of the profile of the air cleaner base.. The Genuine Racecar Sound Effects is what made them faster in somebodies head. The most improvement I have ever seen was around 0.1 sec. Anybody who believes they can 'feel' a tenth in a quarter, would believe the trees moving makes the wind blow.

Back then, many people flipped the dished top of the air cleaner lid upside down, creating a gap between the lid and the pan, so air could get in all the way around. But I don't suppose that many realized that increased air flow meant a leaner A/F mixture, and that you would need to rejet to compensate for it. Then came those cheap chrome aftermarket air cleaners, with just a thin top and bottom plate, which left the filter element open all the way around. Since those still use the stock filter, they work fine, but you do need to rejet for them, at least on carbureted engines.
I disagree completely.
 

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Discussion Starter #19
Only time I worried about jets on the street was if I added headers. At that, most of the time I just enjoyed the torque and mpg increase, and let it be.

Only lid I flipped was on Q-jets, just because that wail sounds so awesome and startles pedestrians. Meh, I guess it worked on the 460 Fords too.

I think the trick to putting boots back in the airbox, is to stuff them in too far, then pull it back out where the groove is.
 

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I should stay away from these types of threads. It is 37* out and too cold to start my workout so....

Statement. If there is no obvious engineering incentive to support your assumption, it probably deserves more scrutiny.

Kawasaki designed a restrictive intake. Reilly? Why?

Cheaper? No, few intakes could be more expensive than OEM vn.

Quieter? No, the only M/C with louder intakes were manual slide individual filter M/C's. Mine is loud. The intakes are intentionally ahead of the operator.

Efficiency. Not sold as high mpg. Original design introduced at a time when mpg was unimportant. I could count on 60 mpg from my '83 Shadow.

Power. Aha. The much increased cost of producing a machine with convoluted intake plenum and 'chambered' exhaust can only point to wave tuned engine performance. Successful wave tuning usually increases the bottom 10%, the middle 15+% and costs 5-7% top end hp.
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I often am asked to tune 2+ hp per cu in V8's. Most are Holley carburetors. If the hp is still increasing above a 10% increase in jet orifice size above original, there is usually a problem elsewhere. Why? Simply put, a carb is a siphoning devise. If you increase just the airflow, you increase the siphoning draw. Once the proper relationship between gas jet and carb venturi is established, few modifications will change it. This is why dyno only carburetors work so well on so many different engines.

A gas jet should be seen as simply a limit on the amount of gas. Carburetor venturi as a limit to the amount of airflow.
 
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