SIMPLE MOD MAY SOLVE POD TUNING HARDSHIPS!

The Alternative Screws that article refers too are Sync Screws.

We eliminate the need to adjust Sync Screws for Idle by BENCH SYNCING the Throttles with the THINNEST Medium available.
3X5 Card
Business Card
Resume' Paper
35mm Film Strips ...

THIS Syncs the Throttles VIRTUALLY Closed.
The setting of IDLE is then made much simpler because the Pilot System supplied the Mixtures to make the Bike run.

No adjustment of the Sync Screws is needed until you actually begin the process of Syncing the Carbs for an accurate Vacuum Sync.

 

I am still a bit puzzled by the whole atmospheric air thing to the kidney ports.

One thing I noticed when cleaning my carbs was that when I passed the air blower nozzle over the ports, the diaphrams slammed open to the top. So, I can assume that with pods, that this increased volume of air the diaphrams will open much quicker/sooner than with the restriction of the factory air box. That being said, this mod that Rick suggested, and Wrench26 is real world testing, should work wonderfully provided the "kidney port pod tubes" allow darn near the same volume of air as the factory setup. In effect this mod should do exactly as it is intended, to allow using pods without having to rejet. However, aside from aesthetics, most use pods looking for a performance increase, and this mod really won't provide that aspect.

The other thing I don't like about pods is that they do not allow wet weather protection to the intake tract. But...K&N does have off-road filter elements for autos and all that is different is a foam sleeve that slips over the filter element. No, if you can find them, that should help.

Oh, and another thing. Wrench26, for an easy way to shape the kidney ports, take a sacrificial carb to a machine shop and have then slice precisely through the horizontal center of the port. Then tap bolt holes on either side of the pieces. With that, you have made a very simply stamping die you can use to form the tube ends precisely. Plus you can then take the two pieces and have a tool and die shop fab die molds from tooling steel that will last a lifetime. Then all you would need is a small press. A table top walnut cracker comes to mind. Cut the correct size aluminium tubing to length, place the die molds in the press, lube the end of the tube to be formed, pull down on the walnut cracker handle, and voila, a precisely shape kidney tube.

 

hey moo1alk i have completed the center die and almost finished the press side of the die using a large get of slip joint pliers. just finishing the filing down to make it have the correct space to account for the 26 Ga metal. works really good with just the center as of now. i ran out of argon for welding so i and on hold. prob just solder for this temp test. hopefully this week i can get the few hours i need. Army pulling me in 5 directions and always need family time. so hopefully i can get out into the garage today after my to jobs and finish test.

 

i REPEAT I REPEAT...... BOGGY ON HOLE SHOT... NO MORE BACKFIRE DECELERATION.... SMELL RICH FUEL MIXTURE..... ENGINE COOLER THAN HAS BEEN.... CAN'T USE NORMAL CHOCK BOGGS DOWN ENGINE.... VERY STRONG PULL MORE THAN WHAT HAS BEEN THERE..... VERY SMOOTHT ECLERATION... ENGINE REVS SMOOTH AND VERY FAST. I BELIEVE WE HAVE DONE IT.... WILL BE PULLING PLUGS AFTER MORNING FORMATION AND CHECKING COLOR AND THEN GET PICTURES.....

 

the first is cylinder 1 and 2 rich.... the second is 3 and 4. have to change onc thing cylinder 4 has the foam breather have to find a thinner diapham.

 

You still have a Lean Condition on the 4-Hole.
Too much air?
-Or-
Not enough Fuel?

If the Lean Condition was alleviated on 1, 2, & 3, ... I'd look for a AIR Leak.
But, ...
You have to check-out everything.
Right Main Jet / Not fowled.
Manifold Leaks / Cracks
Tightness --> DANGER!
E-Tube Clean and Clear
Diaphragm Integrity
Piston Travel
Vacuum Nipple Seal
Float

 

My neighbors have avocado trees so when we want avocados we just pluck one wife is into all the cooking stuff I will ask her to check it out. Thanks

 

TIME The kidney shaped hole never ever saw atmospheric air pressure (14.7 psi at sea level) in the original configuration so how would introducing atmospheric air pressure fix this problem? Remember ricks observations are based on using a shop vac I guess he used some SMOKE to observe the bernelli effect. These carbs draw fuel with differential air pressure (-) the problem is the loss of vacuum not atmospheric air pressure. Ask yourself this why is it that pods dont seem to effect the idle circuit?

 

as far as those plug pics well when you have one plug that far out the whole test is null. If your test setup is not totally equal then that is not a legit test. Try again

 

will do... clean up plugs and reset. i will pull my top again and double check clearance and also verify snyc. along with fixing a leak i have on the valve cover.

 

I can't believe how hostile of a tone people seem to have regarding this subject. Perhaps it is just the internet's way of come across or just the way I'm perceiving it.

Why not just be encouraging for someone to spend time experimenting and learning? It sure seems like the risks are well known so the collaborative encouragement would do little to no harm.

I will most likely never run Pods but if others want to and they can find a way to do it than more power to them. Keep at it!

 

Unless you recently replaced the rubber "donut" washers on the cylinder, you should consider doing so. That could even be the source of your valve cover leak perhaps. You can get a full set from Chacal for under $20 (plus shipping)

 

from the test this after noon. 2 and three has a very nice ring of light tan while 1 and 4 where white... here is the picture

 

What factor of performance in 3 out of 4 Carbs renders this Experiments results NULL.

The Carbs are Individual Units; not one whole entity.

The Experiment showed a Vast improvement in 75-Percent of the Carbs tested.
3 out of 4 showed improvement.

Point seven five zero.
With, ...
Point three two five ... considered an outstanding percentage for striking a baseball thrown from around 60 feet.

I have to say he's doing OK.
Moving in the right direction.
Improvement shown.
Differentials noted.
Satisfactory results upon initial testing.

Prototype Approved.

::: It worked better than 50-50 :::

This isn't the Thread where you come-in and complain about it.
This is the Thread where you come-in with constructive criticism or YOUR idea about what can be done to improve the results.

We're engaged in this experiment because we have nothing better to do.

 

I notice that you have dynojet stage 3 in your sig.

Is that on these carbs?

If so, you may want to change back to the original jets later and do some further testing, so that others will know how this mod will work on standard carbs as well as rejetted ones.

 

I can do that. The one thing that I'm kinda wondering. Once I put the breathers out side the cone my choke is almost doesn't do anything. It picks up a little but not like it use to. It use to run 2-2400 easy now barely makes 1500-1750 when warmed up. I'm going to be doing a valve check this weekend if I'm in town. I believe that is my prob with #4 cylinder. Buts what your guys input on the choke change and change is an understatement. Plugs and engine is very rich and boggy just idling and revving engine. It sounds like pup pup pup to about 2000 then starts to eccelerates fine.

 

Hey - can you grab a camera and post a video (on Youtube)

 

what you want a video of....

 

If it is rich and boggy idleing to 2k, then you are still too rich. +1 on what darkfibre said, do you still have the jet kit in? If so change back to stock jetting, reset mixture screws to 2.5 turns out and then check plugs or colortune for idle. Do plug chops for off idle to verify main fuel mixtures.

 

its only boggy when i have the choke on other than that there no no performance problem once warmed up and no choke....

 

I am going to make a few changes to the set up. im going to have to insert holes into the tube after it goes inside of the cone. I believe that since the there is a jet located under the diapham i believe that this isn't getten enough air flow to allow my choke to idle up like it should. Since it is runnign SO rich when choke on. I believe it isn't getting enough airflow.

Another point with the lean mixture. we go from a restricted inlate tube to a fully open cone that has almost if not double the quantity of air that be push though and the rejetting all you do it try to make the carb atomis more fuel. But im thinking that if i change the main air jet in the carb to allow more air to flow arround the emulsion tube it will better atomis fuel and allow more fuel to be delivered.

Help me out guy what is you im put Rick you know the most that i have read and the write ups from XJ4ever have help so much. what you guys think.

 

Problem solved.

 

+1 to that.
Al

 

but most people can't afford those and they want to look of pods along with the performance.

 

I know. I have stock carbs with pods on my XJ, these CRs are for my CB.

 

I hope i can help you out once i figure this mod out.

 

Are you talking to me? I dont need help, thanks though. My bikes run great without this makeshift mod.

 

Gents, remember that the choke on these bikes is really an enrichment circuit, the opposite of what you expect. By putting the choke on at the idle rpm's you are making the mixture rich, which is what you described happening. Try again with the choke off ...

 

The Jets beneath the Diaphragm are:

Pilot AIR and Main AIR.
Neither one has anything at all to do with "CHOKE"

The "Choke" does not choke.
Rather, ... it is a Extra-Fuel System.

There is the Possibility that the Main AIR and Pilot AIR Jets are Reversed.
It happens.

If the Carbs had a JET KIT Installed, ... you need to return to Stock.

If the Pistons were drilled with an extra hole or the Std Hole enlarged, ...
Return to stock.

The easy way would be Diaphragm Pistons from Parts Carbs.

::: Although you can fuss-around and repair the drilled holes to correct size.

You can "Sweat" a miniature Patch of Shim Stock over the extra hole.
>> Remove Needle Assy <<

You can PLUG a Hole with a Copper B-B ~ Peened and Soldered

Also, ... Solder the "Filed-down, sanded and fitted" HEAD of a Brass Machine Screw into the Hole and remove and dress the threaded shank.

Swapping Parts is easier.

 

The weird this is that until I added the tubes there was no problem with the joke at all. It flood the system. Turns the plugs almost chacolate. So I'm thinking after reading the info on how carbs work that there isn't enough air when choked but just enough when not choked. I'm going to move the main needle C clip down on I believe that put more fuel in. If I'm wrong please tell me. Trying to get the right mixture before really messing with the enrichment port.

 

In a "normal" carb setup, the choke reduces the amount of air coming in to make the fuel mixture richer. Yamaha set it up so that the "choke" adds additional fuel, rather than reducing air flow. So yes, having the choke on will turn the plugs chocolate if the system is off kilter.

Nothing to mess with regarding the enrichment circuit other than making sure it is clean and functional. Follow Rick's guide to setting you pilot jets after doing a bench synch and you should be good to go!

 

Can't you just use partial enrichment? (don't put the 'choke' fully on?)

 

it floods it with very little added. so i need to do some playing

 

8O Ok .. A question ... These are a pod type filter for Mikunis on HD's, Why are they being claimed as the "Ducks Guts " for performance.

Fits CV carburetors only.
http://www.dragstripracer.com/product/p ... tor-by-bcm
BCM (Boyle Custom Moto) Air cleaners are machined from 6061 aluminum, then hand massaged to meet their high standards and insure a quality fit and finish.

BCM enlisted the help of some trusted motor gurus to help in the basket design. This basket design greatly minimizes air restriction and with the addition of the â„¢"vortex cone" you get increased and properly directed air flow. The high percentage open area stainless cage allows more air flow to pass through quickly and easily.

With a lot of help from the guys at Uni Filter the right foam density for a BCM propriety big twin filter element was created. Uni filter cuts and glues the filter specifically for BCM to ensure the best fit.

 

Imagine that a vortex cone, sounds kinda familiar.

 

Fantastic thread guys. Hats off to Wrench26 for his work on this. love the way the pods work. I'll happily switch over to them, when they get this figured out....

 

hey guy i havn't been on in a while been very busy a new baby and all. but i have a few idea that should eliminate my choke problem and the tunnign problem once and for all. i have been soldiering the tubs together making a tight seal from the air in the cone. i believe that the air travelign to the upper area. is needed in more ways than we know. so what im going to do it make four new insert with the seam on the top. this would elimiate the turbulance and also allow the bellow to breather as much as it it needed with out any kinda restrictions. when i complete will let you all know how it goes.

 

Has anyone noticed that on most pods (I have seen) that the rubber that connects the pod to carb is closing upon the small kidney shaped opening? that is of course if your not running streetbrawlers velocity stack theory which seems to work on my bike just fine. This obstruction doesn't say anything about the turbulence but perhaps it could be making an impact somehow? I dunno thought I might throw that out there? :roll:

 

****Update****work in progress but by flipping the tubs and not sealing them I believe it's good. When I finish this last 500 mile test (have put 1500 on with test cruising and just plan beating the pants off the engine it's good). I will publish my finding and conclusion in about 2 weeks or so.

 

dont know if its any help to you guys but I originally had these pods on and it ran ok



but I then installed these and it runs much better , dont ask me why but I guess its the turbulance thing again



also theres a lot of people saying to start off with standard jets which is pointless , at least start using bigger mains and pilots . also a list as to what .mm hitachi jets are as a 43 pilot jet isnt 0.43 mm .

 

idk if it works or not i havnt read through the hole think but jetting and sealing passage ways to drill new ones are not the same at all thats all i have to say dont try this unless you are ready to buy new carbs if it dosnt work

 

Cheap carbs on ebay

Just in case someone wants to try it out.

 

The "Bypass" has been improved upon since this design was submitted.

But, the notion that Drilling some holes into the Intake Horn would ruin the Carbs is bunk.

If the Holes needed too be Plugged after abandoning the prototype; they could be VERY EASILY Plugged with:

Plastic or Rubber Plug or Caps.

NO BIG DEAL.
Easy as Pie.
So sweat.

http://www.stockcap.com/prod_detail.asp?id=117&cat=13

 

can we have the improved upon details refreshed to this thread so we dont have to search the forum to find it please

 

i sent mine into carbking.weebly.com it came back within 4 days cleaner then i ever expected i think he even put new jets in free best part only cost me 13$ plus shipping bike runs great now that i could tune it think ill go ride now for those who are scared to open up these things i was n-eways

 

Yes i will place a new thread once i finish the research of the modifaction/add-on piece. so that people don't have to flip thought all 17 pages.

 

I have a 650 maxim with pods. Would be willing to test this theroy (not with my carbs of course). Solution theroy sounds ok but man gotta agree with fitz, no offense but bullshit talks and positive proof makes us all happy.

 

gladly when i finish my testing. i had to post pone due to exhaust leak. so once i finish my custom exhaust will get back to testing and tuning

 

Before this Prototype got introduced; just about the only bit of advice there was to offer someone tuning for Pods was:

"You got to rejet."

Except that nobody ever really spelled it out.

"You got to rejet, ... over, and over, and over, and over and over again!"

Now, there's something else to try.
Supported by theory instead of guesswork.

 

OK here is the stage one testing. I completed two test one with the tub inserts and one with out inserts.

With inserts
Lost high idle enrichment- would run with enrichment but the idle wouldn't pick up like it always did.

Tried different configurations
1. Tubs soldered together at seam
2. Tubs unsoldered
3. Tubs Unsoldiers and drilled on top

All thee configurations welded the same outcome. didn't effect lean/rich setting and didn't change performance.

Chance two no tubs just shortened boot.
1. I cut boot back to make back of filter meet up with front of carb.

This welded a better lean/rich mixture. more towards richness

Custom exhaust mod.....

Set me back a little but help out with evening out the lean/richness

FINDINGS

1. Stock exhuast will run leaner on the #1 and #4 piston due to exhuats configurations. the headers creates more back pressure on the #2,#3 cylinders. This is in my theary because the #2,3 turn into the #1 and 4 exhuast pipe. cause a clash of the exhuast pulse. helping #2,#3 run richers.

2. If you run stock exhuast and want to run pods this is what you will have to due.( This is just a test and not alot of other bikes have done it.)

1 if you buy the cheap pods cut the boots so that the inner flange is up against the carb
2. Cut a groove in the boot to allow alingment with the kidney opening.
3. install stage jet size +4 into your bike. but from there.

REMEBER THIS IS JUST A 2500 MILE TEST. I HAVE MORE TESTING TO BE COMPLETED. AS I GET GOOD FINDINGS I WILL POST

Edit:
I'm going to tear down my carbs I believe I have a few blocked ports. I need to get larger jets now due to large exhaust pipe. But I believe that after carbs are clean everything should be good. But again I will not know till I finish cleaning and rejet to the correct size. 140 anyone know where I can get them? And an increase pilot jet.