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RonD
For me the induction noise of carbs is too loud. So I went looking for a solution and I thought I would share what I found and trying. 1985 Honda 1200 Goldwing air cleaners.

They seem to be working great. Nice deep sound and quieter. The air horns on top are about 1"x 1 1/2" each. Combined they are bigger then 1 throat of the carb. I don't feel any reduction in power and idle seems about the same. Engine is a basic rebuilt 1.7 to 2.0L specs with carb cam and hydralic lifters.

Cheap too. shipping cost more than the air boxes themselves. A little fabrication of a mounting plate, but pretty much bolt on. Linkage clears.
'73-914kid
Whats the height of the box from the base at the carb to the highest point?
euro911
They actually look like they belong in there.

How much quieter are they (if you can attach a percentage to them)?

Do they clear a stock rain tray OK?

How did you take out the gap with the different height elements?
RonD
They are about 6 1/4" tall. I don't have a rain tray to check clearance but I would suspect they would touch.

The top of the Honda filter has a depression which makes it about the same height as the weber filter. So it just fits.

They are very quiet, better than 50%. Almost silent at low RPM. The sound is not thumpy at higher revs. More uniform, with a bass note.
euro911
Nice mod, Ron. Thanks for posting first.gif

I don't want to lose my rain tray, so if they don't fit, I'll need to look for another solution dry.gif

Dave_Darling
Very cool! This looks like a really worthwhile addition for anyone who uses a carb'ed 914 on the street.


.... Or one with independent throttle bodies in any way...... Hmmmmm..... idea.gif

--DD
yeahmag
These would negate most of the reason for having a rain tray with carbs... Would they not?

-Aaron

QUOTE(euro911 @ Sep 18 2012, 10:11 AM) *

Nice mod, Ron. Thanks for posting first.gif

I don't want to lose my rain tray, so if they don't fit, I'll need to look for another solution dry.gif

VaccaRabite
Rain tray also protects the electrical wiring and keeps water out of the engine bay in general. If you run w/o a tray you need to be sure the battery is covered so you are not leaching watery battery acid back down into the hell hole.

Zach
yeahmag
The battery is exposed regardless of having a rain tray or not.
JmuRiz
Those air cleaners are really cool...they'd look good if you had some side-draft carbs (on other cars). I remember seeing a really cool Mercedes M110 with side-draft webers on it, for a daily driver those covers would be perfect.
wobbletop
Anyone found anything for a -6?
SirAndy
QUOTE(yeahmag @ Sep 18 2012, 10:43 AM) *

The battery is exposed regardless of having a rain tray or not.

agree.gif

The rain tray does not really protect the battery much anyways ...
popcorn[1].gif
SirAndy
QUOTE(wobbletop @ Sep 18 2012, 11:15 AM) *
Anyone found anything for a -6?

Porsche. It's called a "911" ...
biggrin.gif
euro911
My battery has a plastic cover (came with the AA battery tray/mount kit), but I like the rain tray because it catches most of the rain water should I encounter an impromptu storm (like the evening we came home from the Rt-66) dry.gif

I think with the GL housings by themselves, the carbs could still ingest a fair amount of water without a rain tray in place. I know a few folks who have the fiberglass 'hats' (and no tray) and have ingested water while parked.

Maybe a custom (shallower) tray is one solution idea.gif


EDIT:
Old 911s don't have rain trays due to the lack of space from the stock air filter housing, but there is an optional tray for 912s.
'73-914kid
Have you noticed any difference in the air/fuel ratio after installing them? I'm in desperate need of quieting my carbs down with my school commute every weekend... This is a great option, thanks for sharing! beer.gif
VaccaRabite
Air cleaners off a 912 work, and can be adapted to fit IDFs.

Before I decided to go FI, this was the route I was going to take.

Zach
euro911
idea.gif I have a few sets of those, but they're set up for Solex P40IIs. I'll check to see if they fit Weber IDFs
gothspeed
Looks good smile.gif
RonD
I balanced and tuned carbs after I put them on and watched my idle very closely and really didn't see much of a differance between putting the tops on the filters and the air box top with the horns. Driveablilty wise there are no flat spots that I can tell. We have some pretty steep canyon roads here in Boulder and it pulled real strong from low RPMs.

I probably spent less then $75 on the project. The 356 or 912 air cleaners I saw for sale were $200 plus and needed adapter plates to work with Webers, and didn't seem to quite fit anyway.

I thought of motorcycles because I have a BMW R90/6 which is essentially half type 4 engine and its super quiet. BMW boxes need more fabrication to fit, so just kept looking and found these. The earlier Goldwing boxes are not as tall and might work also
ldsgeek
The GL1000 (shown by RonD), GL1100 and GL1200 should all have something similar. this is a great idea. For those who don't know the setup, this bolts to the top of the air plenum that connects the 4 carbs on these bikes. Any cycle salvage place (Coopers is in Franklin, NH near me) should have these available.
KaptKaos
Nominate for classic thread status. This is a common issue, with a very innovative solution.

Nice job!
Gint
Interesting. Hmmm....

Seems like you could fab up a couple of air boxes out of sheet aluminum or galvanized steel without too much trouble also.
ClayPerrine
I took the stock air cleaner off my six and put on K&N watershield air cleaners because I like the sound of the six stacks at full song.


Just got to listen to it too. My car is back up and running. driving.gif

piratenanner.gif cheer.gif mueba.gif aktion035.gif
02loftsmoor
nice out of the box thinking! a clean look
Cap'n Krusty
QUOTE(wobbletop @ Sep 18 2012, 10:15 AM) *

Anyone found anything for a -6?


Well, there's the one designed and installed by Porsche ..................

The Cap'n
wobbletop
QUOTE(Cap'n Krusty @ Dec 27 2012, 03:38 PM) *


Well, there's the one designed and installed by Porsche ..................

The Cap'n


I'm new to this stuff. I guess you're referring to the Zenith covers? Would a particular model fit a 3.0 with webers?


Dave_Darling
The triple Webers in the 914-6 used a single combined air cleaner. Almost the same as the one from the 1969 911T, which makes sense because the Six motor is almost identical to the 69 T motor.

I'm pretty sure that's what the Cap'n was referring to.

--DD
Mark Henry
I'm to believe any /6 carb airfilter assy. will fit but you might have to cut off the snorkel.
Is this correct?

Is the bolt pattern the same on both the zenith and weber carb tops?
JamesM
CB performance sells covers for use when turbocharging, why not just run them without the turbo? They have a bunch of different models including a low profile one for 356s that might fit under a rain tray. Looks like it would be easy to pipe the inlets whereever you want.


http://www.cbperformance.com/ProductDetail...oductCode=7313T
euro911
Interesting idea.gif
kgruen2
QUOTE(ldsgeek @ Sep 18 2012, 03:20 PM) *

The GL1000 (shown by RonD), GL1100 and GL1200 should all have something similar. this is a great idea. For those who don't know the setup, this bolts to the top of the air plenum that connects the 4 carbs on these bikes. Any cycle salvage place (Coopers is in Franklin, NH near me) should have these available.


I know this is a very old thread, but...........In the case of the Honda Goldwing air boxes, does it matter which way the air intake horns are pointed, towards the front or the rear?
porschetub
No makes no difference,I like this idea for a 4 just makes sense,the sound is fun for a while....
I feel lucky to have a six with stock air cleaner ,hate to have to buy one they are getting a bit crazy pricewise.
Always like the Alfa setup for Dellorto's and Webers on the early carb cars no reason it won't work on a T4 without simple mods.
Click to view attachment
michael7810
QUOTE(RonD @ Sep 17 2012, 10:35 PM) *

For me the induction noise of carbs is too loud. So I went looking for a solution and I thought I would share what I found and trying. 1985 Honda 1200 Goldwing air cleaners.

They seem to be working great. Nice deep sound and quieter. The air horns on top are about 1"x 1 1/2" each. Combined they are bigger then 1 throat of the carb. I don't feel any reduction in power and idle seems about the same. Engine is a basic rebuilt 1.7 to 2.0L specs with carb cam and hydralic lifters.

Cheap too. shipping cost more than the air boxes themselves. A little fabrication of a mounting plate, but pretty much bolt on. Linkage clears.


I just finished with the same mod and couldn't be happier. Cost of the filter boxes off eBay was $24 each including shipping and I used 85 Gold Wing Aspencade 1200cc boxes. I've driven about 10 miles and did not notice any changes in A/F, idle speed or power. I did notice a HUGE reduction of intake noise and now I can hear the exhaust. The ultimate test is driving up an incline on the highway with the windows up which I will attempt sometime before WCR. Below are a few pictures of how it goes together...basically as RonD describes. And thanks to Keith914 who gave me his lessons learned.

Mounting plate made from 1/8" aluminum:

Click to view attachment

Before installing the old K&N-type filter. You can't see it here but I had to grind off the ends of the chrome bottom plate to fit the GW air box opening.

Click to view attachment

With filter cover installed...I had to weld in a longer 1/4-20 bolt for the wing nut and dimple the top of the chrome top to make it all fit properly:

Click to view attachment
7TPorsh
Congrats! I did this mod too and I met a fellow from Laguna Beach at the G&R Swap that had it as well.

This is an easy 80% reduction of intake noise and I highly recommend this mod to everyone.
Elliot Cannon
I like the noise my carbs make. Especially when I'm wearing these. biggrin.gif
Beach914
QUOTE(7TPorsh @ May 18 2017, 03:37 PM) *

Congrats! I did this mod too and I met a fellow from Laguna Beach at the G&R Swap that had it as well.

This is an easy 80% reduction of intake noise and I highly recommend this mod to everyone.

That was probably Keith914. He made the same set up for his t4. But now he's doing his six project.
lonewolfe
QUOTE(euro911 @ Dec 30 2012, 10:45 AM) *

Interesting idea.gif

Those CB Covers are made to go with an air box. Those covers have no filters inside. I've been thinking about gabbing an air box attached to the covers with silicon hoses.

There's a company in Germany with a similar setup as I've been working on. They are call CSP Performance. Their airbox kits start at 799.00 Euro's if I'm not mistaken but items a chunk of change for a plastic airbox, carb covers, silicon hoses and hardware.
euro911
QUOTE(lonewolfe @ May 18 2017, 07:26 PM) *
QUOTE(euro911 @ Dec 30 2012, 10:45 AM) *
Interesting idea.gif
Those CB Covers are made to go with an air box. Those covers have no filters inside. I've been thinking about gabbing an air box attached to the covers with silicon hoses.

There's a company in Germany with a similar setup as I've been working on. They are call CSP Performance. Their airbox kits start at 799.00 Euro's if I'm not mistaken but items a chunk of change for a plastic airbox, carb covers, silicon hoses and hardware.
Yeah, I looked into those CB covers way back when, and still might go that route if I keep the 'BB' after finishing up the '71 (which has F.I.) confused24.gif

It'll be project# 1,785 laugh.gif
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