Author Topic: The Airpod Solution  (Read 3965 times)

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Offline JWilde

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The Airpod Solution
« on: May 17, 2016, 06:41:54 AM »
A friend of mine showed me what a friend of his did to get a vacuum, similar to an airbox, on Airpods. Nifty Idea.

Offline flybox1

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Re: The Airpod Solution
« Reply #1 on: May 17, 2016, 06:45:36 AM »
"Electrical Tape - For all those times you can't tune your pods correctly"
'78 750K (F3 engine) PD42b's, Modified airbox w/K&N  filter, 40/110 jets, 1 needle shim, IMS@ 1 turn out. Kerker + Cone 18" QuietCore

Past Bikes
1974 550K0 (stock), 1973 CB350F (stock), 1983 Yamaha XS400K (POS)
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"Knowledge without mileage equals bullsh!t" - Henry Rollins

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Offline JWilde

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Re: The Airpod Solution
« Reply #2 on: May 17, 2016, 06:48:02 AM »
"Electrical Tape - For all those times you can't tune your pods correctly"

Yep. Quick fix that gets things running properly. I dont have "garage time" with two kids and my own business. Just not possible.

Additionally, I kinda like the way it looks!!!

Offline flybox1

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Re: The Airpod Solution
« Reply #3 on: May 17, 2016, 07:05:52 AM »
When you do get garage time, I have a good .pdf for servicing those carbs.  Let me know.
Those air cutoff diaphragms are probably haggered, and the primary/secondary jet tubes clogged.
Easy fix, but its a lengthy process.  ::)
'78 750K (F3 engine) PD42b's, Modified airbox w/K&N  filter, 40/110 jets, 1 needle shim, IMS@ 1 turn out. Kerker + Cone 18" QuietCore

Past Bikes
1974 550K0 (stock), 1973 CB350F (stock), 1983 Yamaha XS400K (POS)
77/78 cool 2 member #3
"Knowledge without mileage equals bullsh!t" - Henry Rollins

"This is my CB. There are many like it, but this one is mine…"

Offline JWilde

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*EDIT*
« Reply #4 on: May 17, 2016, 07:17:52 AM »
When you do get garage time, I have a good .pdf for servicing those carbs.  Let me know.
Those air cutoff diaphragms are probably haggered, and the primary/secondary jet tubes clogged.
Easy fix, but its a lengthy process.  ::)

Ive been speaking to your buddy "calj" over the phone and weve been having great convos. He spoke VERY highly of you and said you are the go-to guy on this. I trust his judgment.

So let me ask:

A dude rejetted and rebuilt my carbs (so all is in good working order) and put the pods on. The only thing Ive noticed is, it runs better with the choke in the Open position. When it is in the opposite, CLOSED position, the RPMS drop off at about 5000 and it sounds like it wants to stall.

The plugs are black. Whats going here? Do I need to restrict the fuel or the air, as the electrical tape would be a temporary fix until till I do as you wisely say, and really take care of this
« Last Edit: May 17, 2016, 07:21:44 AM by JWilde »

Offline Ericcb750

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Re: The Airpod Solution
« Reply #5 on: May 17, 2016, 07:29:39 AM »
Flybox is the man when it comes to this carb stuff. He's been in-valuable in helping me get my PD Style carbs actually running correctly, after I pulled them off and put them back on about 5-6 times!!! He's a great guy and very knowledgable on this subject so Calj was spot on. I wish I could help you but I don't really know jack about the DOHC Carbs....although they're pretty much the same CV style Keihin that's on my Harley.

Best of luck.
1978 CB750K
1978 CB750F super sport
2005 Sportster 1208

Offline JWilde

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Re: The Airpod Solution
« Reply #6 on: May 17, 2016, 07:35:06 AM »
Flybox is the man when it comes to this carb stuff. He's been in-valuable in helping me get my PD Style carbs actually running correctly, after I pulled them off and put them back on about 5-6 times!!! He's a great guy and very knowledgable on this subject so Calj was spot on. I wish I could help you but I don't really know jack about the DOHC Carbs....although they're pretty much the same CV style Keihin that's on my Harley.

Best of luck.

Thanks Eric. Yeah Ive been told FLY is the Yoda of Carbs and that the Force is strong with him!

Offline flybox1

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Re: The Airpod Solution
« Reply #7 on: May 17, 2016, 07:39:09 AM »
haha...go easy guys  ::)
JW, just so i'm clear, which bike are we referring to....your 350F or the pictured DOHC 750?
'78 750K (F3 engine) PD42b's, Modified airbox w/K&N  filter, 40/110 jets, 1 needle shim, IMS@ 1 turn out. Kerker + Cone 18" QuietCore

Past Bikes
1974 550K0 (stock), 1973 CB350F (stock), 1983 Yamaha XS400K (POS)
77/78 cool 2 member #3
"Knowledge without mileage equals bullsh!t" - Henry Rollins

"This is my CB. There are many like it, but this one is mine…"

Offline JWilde

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Re: The Airpod Solution
« Reply #8 on: May 17, 2016, 07:40:51 AM »
haha...go easy guys  ::)
JW, just so i'm clear, which bike are we referring to....your 350F or the pictured DOHC 750?

The carb issue is with the 350f.  750 is stock and garaged and will not be ridden until I have more experience.

Offline flybox1

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Re: The Airpod Solution
« Reply #9 on: May 17, 2016, 07:48:02 AM »
OK.   If you have to use the choke AFTER the bike is warm and you're out riding, it means your jetting is wrong for your intake and exhaust setup.  Period.   The ONLY time you should use choke is on startups.
If you want to get your hands dirty, I can talk you through it  ;)  Otherwise, take the bike back to the guy who did the work and tell him it isn't right.
'78 750K (F3 engine) PD42b's, Modified airbox w/K&N  filter, 40/110 jets, 1 needle shim, IMS@ 1 turn out. Kerker + Cone 18" QuietCore

Past Bikes
1974 550K0 (stock), 1973 CB350F (stock), 1983 Yamaha XS400K (POS)
77/78 cool 2 member #3
"Knowledge without mileage equals bullsh!t" - Henry Rollins

"This is my CB. There are many like it, but this one is mine…"

Offline JWilde

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*edit*
« Reply #10 on: May 17, 2016, 07:49:58 AM »
OK.   If you have to use the choke AFTER the bike is warm and you're out riding, it means your jetting is wrong for your intake and exhaust setup.  Period.   The ONLY time you should use choke is on startups.
If you want to get your hands dirty, I can talk you through it  ;)  Otherwise, take the bike back to the guy who did the work and tell him it isn't right.

I did talk to him about it briefly this weekend (he was on the move and was only at the garage for like 5 min) and he said I need to adjust the mixture via the screws. I hate arguing and dont really want to argue with him or drag this out at all. If need be I will take it to someone better qualified to rejet. in the meantime, will the tape work?

And can you explain why, in its current state, the bike runs better with the choke open? That is, can you explain  the technical reason of why the jets arent working with it.

Also is there harm being done to the engine with it running as it is?
« Last Edit: May 17, 2016, 07:55:20 AM by JWilde »

Offline flybox1

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Re: The Airpod Solution
« Reply #11 on: May 17, 2016, 07:55:47 AM »
I can't say that ONLY adjusting the air screws is all that's needed. I have a hunch that it will take more.
We need to know the sizes/brands of jets he used in there.  If you can get that info, it'd really help us figuring out your next steps.
Tape your pods? No.  Its not exact.  You dont know how much to cover.  You'd be guessing.
If you want this bike to run GREAT...we need to be exact.


'78 750K (F3 engine) PD42b's, Modified airbox w/K&N  filter, 40/110 jets, 1 needle shim, IMS@ 1 turn out. Kerker + Cone 18" QuietCore

Past Bikes
1974 550K0 (stock), 1973 CB350F (stock), 1983 Yamaha XS400K (POS)
77/78 cool 2 member #3
"Knowledge without mileage equals bullsh!t" - Henry Rollins

"This is my CB. There are many like it, but this one is mine…"

Offline slikwilli420

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Re: The Airpod Solution
« Reply #12 on: May 17, 2016, 07:56:32 AM »
What's happening is that your carbs may be in good working order with a stock airbox, but are not set up properly to run pods, which is near impossible. The original airbox has a velocity stack built in which your pods do not. If you want to look cool, bolt on some velocity stacks with some BBR filters. That way you get the velocity stack function, no airbox and you can jet more easily.
All you gotta do is do what you gotta do.

Vintage Speed Parts Mashup: http://forums.sohc4.net/index.php?topic=133638.0
Rickman CR Parts Kit Refresh: http://forums.sohc4.net/index.php/topic,154837.0.html
AHRMA CB750 Racer: http://forums.sohc4.net/index.php/topic,158461.0.html
AHRMA Superbike Heavyweight Racer: http://forums.sohc4.net/index.php/topic,173120.0.html
'76F CB750 Patina Redemption: http://forums.sohc4.net/index.php/topic,174871.0.html

Offline JWilde

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Re: The Airpod Solution
« Reply #13 on: May 17, 2016, 08:01:39 AM »
I can't say that ONLY adjusting the air screws is all that's needed. I have a hunch that it will take more.
We need to know the sizes/brands of jets he used in there.  If you can get that info, it'd really help us figuring out your next steps.
Tape your pods? No.  Its not exact.  You dont know how much to cover.  You'd be guessing.
If you want this bike to run GREAT...we need to be exact.

OK. I like that youre precise. Great sign.

So I'll leave the guy for a while (dont feel like dealing with it at the moment. I get the sense he may feel insulted if I challenge or question the quality of his work, and Im so busy with the kids and business, I dont have the capacity for the added stress). In the meantime I will start with 75% coverage of tape, like my friend's friend did, and see how it runs.

A LOOONG time ago I was really good at dialing and tuning car carbs (like on my 62 chevy 409 and 64 buick) but this is a different animal and there are FOUR pain in the ass carbs to deal with. I'll work up to it, but tape for now. When I get the info from the dude, I'll then post it and the REAL work can begin.

Like I said I love the way that tape looks. Call me crazy! lol

Offline flybox1

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Re: The Airpod Solution
« Reply #14 on: May 17, 2016, 08:03:17 AM »
With either stacks or pods, you will have to get on a dyno and do a few runs for A/F, or, do a series of plug chops and adjust  jetting until it is adequate.  Both can be done, but neither will be as easy as installing the airbox and original keihin jet sizes.
'78 750K (F3 engine) PD42b's, Modified airbox w/K&N  filter, 40/110 jets, 1 needle shim, IMS@ 1 turn out. Kerker + Cone 18" QuietCore

Past Bikes
1974 550K0 (stock), 1973 CB350F (stock), 1983 Yamaha XS400K (POS)
77/78 cool 2 member #3
"Knowledge without mileage equals bullsh!t" - Henry Rollins

"This is my CB. There are many like it, but this one is mine…"

Offline strynboen

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Re: The Airpod Solution
« Reply #15 on: May 17, 2016, 08:03:32 AM »

« Dato: Maj 13, 2016, 02:17:56 pm »

try to tape 1/3 of the pod filter off..and take a ride.
.this vill indikate/do the job that the choke do now...the bike vill run fine.
.but you vill Loose some pontentiel of full power
but a easy and qvik vay to test..
« Last Edit: May 17, 2016, 08:05:52 AM by strynboen »
i kan not speak english/but trying!!
http://forums.sohc4.net/index.php?topic=60973.0
http://forums.sohc4.net/index.php?topic=144758.0
i hate all this v-w.... vords

Offline JWilde

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Re: The Airpod Solution
« Reply #16 on: May 17, 2016, 08:04:36 AM »
hnmmm thorth i had a part of that bad idea..taping the pods for less air to the engine
« Dato: Maj 13, 2016, 02:17:56 pm »

try to tape 1/3 of the pod filter off..and take a ride.
.this vill indikate/do the job that the choke do now...the bike vill run fine.
.but you vill Loose some pontentiel of full power
but a easy and qvik vay to test..

Thank you!

Offline flybox1

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Re: The Airpod Solution
« Reply #17 on: May 17, 2016, 08:09:18 AM »
After your bike is warm, it should operate best when the choke lever is pressed DOWN, pointing at the ground.
This OPENS the butterfly valves.

the lever should be UP (closed) for starts.

The plugs will foul, or the bike will 'choke out' if this lever is lifted towards the tank under hot running conditions.
If it is lifted, and it sounds like you are running with this lever up a bit, you are cutting off the air supply to the carbs, fouling the plugs.
get it pressed down once the bike is hot....1/4 - 1/3 tape on the pods is a good place to start


« Last Edit: May 17, 2016, 08:11:40 AM by flybox1 »
'78 750K (F3 engine) PD42b's, Modified airbox w/K&N  filter, 40/110 jets, 1 needle shim, IMS@ 1 turn out. Kerker + Cone 18" QuietCore

Past Bikes
1974 550K0 (stock), 1973 CB350F (stock), 1983 Yamaha XS400K (POS)
77/78 cool 2 member #3
"Knowledge without mileage equals bullsh!t" - Henry Rollins

"This is my CB. There are many like it, but this one is mine…"

Offline strynboen

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Re: The Airpod Solution
« Reply #18 on: May 17, 2016, 08:11:18 AM »
no dont thank me..its aktuly a bad idea.
..go 2 numbers up in jet instead..it vill give more power..now you tape it..you are not getting air for a perfekt mix
but still it vil run fine..and start easyer.

.bigger jet gives more fuel..and that vill be perfekt for the more air through the open pot filter..1+1=3
i kan not speak english/but trying!!
http://forums.sohc4.net/index.php?topic=60973.0
http://forums.sohc4.net/index.php?topic=144758.0
i hate all this v-w.... vords

Offline JWilde

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Re: The Airpod Solution
« Reply #19 on: May 17, 2016, 08:20:36 AM »
After your bike is warm, it should operate best when the choke lever is pressed DOWN, pointing at the ground.
This OPENS the butterfly valves.

the lever should be UP (closed) for starts.

The plugs will foul, or the bike will 'choke out' if this lever is lifted towards the tank under hot running conditions.
If it is lifted, and it sounds like you are running with this lever up a bit, you are cutting off the air supply to the carbs, fouling the plugs.
get it pressed down once the bike is hot....1/4 - 1/3 tape on the pods is a good place to start

Maybe Im not understanding. The bike now DOES run BEST when the lever is pointing toward the footpegs. There is an arrow on it that says OPEN and when that arrow is pointing to the ground and "clicked into position" it is then the bike runs great. When I move it AWAY from the ground/left foot peg and back up toward the gas tank, THATS when it runs like #$%*. Is that how its supposed to be? Or did I use the incorrect language to describe an open and closed choke?

Offline flybox1

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Re: The Airpod Solution
« Reply #20 on: May 17, 2016, 08:24:43 AM »
small pictures, but notice two things.
1. the position of the choke lever is up/closed in both pictures
2. the butterfly plates closing off the intake side of the carb throat

(once the lever is pressed down (OPEN), the butterfly plates rotate horizontally, opening the carb throats for max volume/flow once the bike is hot)


'78 750K (F3 engine) PD42b's, Modified airbox w/K&N  filter, 40/110 jets, 1 needle shim, IMS@ 1 turn out. Kerker + Cone 18" QuietCore

Past Bikes
1974 550K0 (stock), 1973 CB350F (stock), 1983 Yamaha XS400K (POS)
77/78 cool 2 member #3
"Knowledge without mileage equals bullsh!t" - Henry Rollins

"This is my CB. There are many like it, but this one is mine…"

Offline JWilde

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Re: The Airpod Solution
« Reply #21 on: May 17, 2016, 08:31:23 AM »
small pictures, but notice two things.
1. the position of the choke lever is up/closed in both pictures
2. the butterfly plates closing off the intake side of the carb throat

(once the lever is pressed down (OPEN), the butterfly plates rotate horizontally, opening the carb throats for max volume/flow once the bike is hot)




Holy Crap! Then I dont have a problem. What Ive been doing is experiencing the problem when the choke is "UP"

Its runs best when "down" so Im OK then.....right?

Offline flybox1

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Re: The Airpod Solution
« Reply #22 on: May 17, 2016, 08:34:04 AM »
UP position for starts....as it warms, and you hear idle increasing, start pressing the choke DOWN.
Once it can idle with the lever all the way down, ride off  8)
'78 750K (F3 engine) PD42b's, Modified airbox w/K&N  filter, 40/110 jets, 1 needle shim, IMS@ 1 turn out. Kerker + Cone 18" QuietCore

Past Bikes
1974 550K0 (stock), 1973 CB350F (stock), 1983 Yamaha XS400K (POS)
77/78 cool 2 member #3
"Knowledge without mileage equals bullsh!t" - Henry Rollins

"This is my CB. There are many like it, but this one is mine…"

Offline JWilde

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Re: The Airpod Solution
« Reply #23 on: May 17, 2016, 08:37:23 AM »
UP position for starts....as it warms, and you hear idle increasing, start pressing the choke DOWN.
Once it can idle with the lever all the way down, ride off  8)

Excellent! No tape, No mechanic hassles. Today is a good day!!!!!!

Now, what about a loose steering column. My other mechanic says then he pushes on the bars the wheel just clunks to the side.

My friend who has been riding for a while says its better to have a loose column for more manuverability. Your thoughts?

Offline flybox1

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Re: The Airpod Solution
« Reply #24 on: May 17, 2016, 08:41:57 AM »
Sorry, but your friend is a dumb@$$...and I mean that in the kindest bro-speak.  ;D
Your steering should be smooth but tight. Not rough, clunking, noisy. 
The stock ball bearings often wear grooves in their races with use causing the described clunkiness.
Time to install new roller bearings. 
$40 and 3-4 hrs.
« Last Edit: May 17, 2016, 08:52:09 AM by flybox1 »
'78 750K (F3 engine) PD42b's, Modified airbox w/K&N  filter, 40/110 jets, 1 needle shim, IMS@ 1 turn out. Kerker + Cone 18" QuietCore

Past Bikes
1974 550K0 (stock), 1973 CB350F (stock), 1983 Yamaha XS400K (POS)
77/78 cool 2 member #3
"Knowledge without mileage equals bullsh!t" - Henry Rollins

"This is my CB. There are many like it, but this one is mine…"