Author Topic: Cheapo Pod filters....Why not?  (Read 5833 times)

Offline 8Ball

  • Mr. Clean
  • True Member
  • ****
  • Posts: 881
Cheapo Pod filters....Why not?
« on: April 02, 2013, 12:42:24 pm »
If you look around on the internet, you will find allot of hate aimed at the use of pod filters, but little to no facts behind the reason for the sentiment. I figured that I should put some light to it.

First of all, I have a '79 GS550 with VM slide carbs. The guy I bought this project from, had gathered a bunch of parts for it, including a set of Emgo pods.

Here they are on the bike, after I rebuilt the carbs:


If you remove the rubber boot from the pretty, shiny chrome part and put it on the bike, you notice a couple of things:
1. The actual opening is much smaller than the carb throat. This causes resistance in the air flow (particularly at high RPMs) and the step in size causes turbulence, disrupting the laminar flow.
And 2. The boot blocks the air passages to the pilot jet and air pilot screw circuits.



On CV type carbs, the boot would block the vent for the slide diaphragm, which would cause issues withe the movement of the carb slide:


The original air box boots are shaped like a velocity stack to give the air a smooth flow into the carb throat. This is one of the center boots for my GS. The outside boots, actually look like elbows to turn the air 90 degrees into the throat:


I ordered a set of K&N filters, but while I was waiting, I figured I'd play around with the Emgos. I cut the hole out and installed the original boot in the pod:



This would give you the smooth laminar flow, but would not address the poor filtering that the metal mesh provides. It would, also, require getting two more boots from another airbox, because the elbow shape of the 1 and 4 boots would not work well.


Now my K&N arrived. For the GS550 they have a kit that has two short and two longer filters (#RC0884). That way the outer filters don't hit the frame.



Looking down the filter, you see that there is no step, or change in the inner diameter, and the shape of the boot flares inside the filter to act as a velocity stack.



So when someone ridicules your el cheapo chrome filters.......well, now you know.
Quote from: jeff5150
just follow 129 on the map towards nc til it looks like a kid drawing it had a siezure
Quote from: Tomsljr
Know the difference between crack heads and Gap addicts? I have heard of people quitting crack.

I find a Soap Box comes in handy when getting on and off my High Horse!

Offline Striker

  • Slow Down, Watch the idiots on 4 wheels
  • Member
  • ***
  • Posts: 139
Re: Cheapo Pod filters....Why not?
« Reply #1 on: April 03, 2013, 07:52:15 am »
Thank you for doing that write up.  I want be using any cheap filters any time soon.  What did you use to clean them carbs up?   They look really good.  Also on the pic with the cv carbs on the #2 carb that is open, is it stuck that way from where the boot was blocking the vent?
1963/73  Harley Davidson xlch 1100
High Crane 4 Electronic ignition
Cycle Electric Generator
S&S Super E Carb
Shorty Slant Drag Pipes
Custom Paint
Sparky Spark coils and Plug wires

Offline 8Ball

  • Mr. Clean
  • True Member
  • ****
  • Posts: 881
Re: Cheapo Pod filters....Why not?
« Reply #2 on: April 03, 2013, 10:01:27 am »
The picture of the CV carb is just one that I got off the Internet and circled tge vent hole.  That one is not mine.  I just used it as an example to show the vent.
Quote from: jeff5150
just follow 129 on the map towards nc til it looks like a kid drawing it had a siezure
Quote from: Tomsljr
Know the difference between crack heads and Gap addicts? I have heard of people quitting crack.

I find a Soap Box comes in handy when getting on and off my High Horse!

Offline gotgixers

  • Gixxersaurous rider
  • Legendary Member
  • *****
  • Posts: 3321
  • Old Skool GSXR 7/12
Re: Cheapo Pod filters....Why not?
« Reply #3 on: April 03, 2013, 11:46:07 am »
sorry the filters were crap Butch. It's the only set of Emgo's I have bought. It was the 1st set that popped up on flea-bay, and I was trying to save $ you know. And it is only a 550 after all. But I guess they are really not even fit for a small bike ....sux... :-[
I PITY THE FOOL, THAT DONT RIDE OLDSCHOOL


Offline 8Ball

  • Mr. Clean
  • True Member
  • ****
  • Posts: 881
Re: Cheapo Pod filters....Why not?
« Reply #4 on: April 03, 2013, 11:56:39 am »
With as many parts as you supplied with the bike, buying a set of filters was no problem. 

I actually had posted this on another site months ago because they would just lay into anyone that put them on their bike, but they never told the poor guy WHY it was a bad idea.  Honestly, I think most of them didn't know why.  I think they were just spewing information that someone else told them.  I just figured I'd explain it....and I had a perfect set of filters to SHOW it.

Since Striker had asked a question in the build thread that concerned pods, I figured I'd post the info on ETB as well.
« Last Edit: April 03, 2013, 11:57:39 am by 8Ball »
Quote from: jeff5150
just follow 129 on the map towards nc til it looks like a kid drawing it had a siezure
Quote from: Tomsljr
Know the difference between crack heads and Gap addicts? I have heard of people quitting crack.

I find a Soap Box comes in handy when getting on and off my High Horse!

Offline IanC

  • Administrator
  • Legendary Member
  • *******
  • Posts: 2119
  • Fast from the Past
Re: Re: Re: Cheapo Pod filters....Why not?
« Reply #5 on: April 03, 2013, 04:45:31 pm »
With as many parts as you supplied with the bike, buying a set of filters was no problem. 

I actually had posted this on another site months ago because they would just lay into anyone that put them on their bike, but they never told the poor guy WHY it was a bad idea.  Honestly, I think most of them didn't know why.  I think they were just spewing information that someone else told them.  I just figured I'd explain it....and I had a perfect set of filters to SHOW it.

Since Striker had asked a question in the build thread that concerned pods, I figured I'd post the info on ETB as well.

This other site isn't GS related is it? Sounds like a GS site I used to frequent.
1978 Suzuki GS1000EC - Completely custom.
2012 Triumph Daytona 675R

Offline 8Ball

  • Mr. Clean
  • True Member
  • ****
  • Posts: 881
Re: Cheapo Pod filters....Why not?
« Reply #6 on: April 03, 2013, 07:27:33 pm »
No, it's cafe racer related...and they are BRUUU-TALL to new members.  There are a few old timers (and by that I don't mean age-wise, cuz' I think the worst of them are younger than me) that basically run the tone there.  But if you get can get past that, there is a lot of good info there.  They just have the sentiment that "Cafe Racers" should be more about vintage "racer" than a style or look.   





.....and there are a lot of New Yorkers on the site, with all of the NY attitude.
Quote from: jeff5150
just follow 129 on the map towards nc til it looks like a kid drawing it had a siezure
Quote from: Tomsljr
Know the difference between crack heads and Gap addicts? I have heard of people quitting crack.

I find a Soap Box comes in handy when getting on and off my High Horse!

Offline gotgixers

  • Gixxersaurous rider
  • Legendary Member
  • *****
  • Posts: 3321
  • Old Skool GSXR 7/12
Re: Cheapo Pod filters....Why not?
« Reply #7 on: April 04, 2013, 02:36:19 am »
That's what I was thinking too Ian ...LOL....

And yeah, those cafe racer type sites can be very brutal .......too much so, for their own good ...
« Last Edit: April 05, 2013, 03:47:48 am by gotgixers »
I PITY THE FOOL, THAT DONT RIDE OLDSCHOOL


Offline jeff5150

  • livin the po life!!
  • Legendary Member
  • *****
  • Posts: 2157
Re: Cheapo Pod filters....Why not?
« Reply #8 on: April 04, 2013, 03:34:49 pm »
thats why i always liked the k&n filters.....
81 gl1100....

Offline 2wheeltech

  • True Member
  • ****
  • Posts: 329
Re: Re: Cheapo Pod filters....Why not?
« Reply #9 on: April 08, 2013, 01:33:21 am »
Great write up.. id like to add too that putting pods on mechanical slide carbs like shown, with ample jetting will add quite a bit of power and it will run great when properly tuned... what you didnt mention tho is trying to put pods on your gsxr or ninja with vacuum style carbs, no matter the jetting or pod style, it is almost impossible to get the proper acceleration throughout the rpm range due to velocity and vacuum issues for the slide period..

Sent from my SCH-R950 using Tapatalk 2

Offline 8Ball

  • Mr. Clean
  • True Member
  • ****
  • Posts: 881
Re: Cheapo Pod filters....Why not?
« Reply #10 on: April 08, 2013, 07:36:14 am »
You are right.  I mentioned it in my build thread, where the original question that prompted me to post this thread came up.  But, yeah, I neglected to say it here.  CV carbs are infinitely harder to get tuned right with pods...even good ones.
Quote from: jeff5150
just follow 129 on the map towards nc til it looks like a kid drawing it had a siezure
Quote from: Tomsljr
Know the difference between crack heads and Gap addicts? I have heard of people quitting crack.

I find a Soap Box comes in handy when getting on and off my High Horse!

Offline jameson079

  • Newbie
  • *
  • Posts: 1
Re: Cheapo Pod filters....Why not?
« Reply #11 on: September 20, 2013, 04:23:57 am »
Hi guys,

Thanks for the great write up and explaining why some old timers bag on pods. Quick question. I was on another forum and they were saying Dual Flange Oval Universal Air Filters (like these http://www.knfilters.com/search/univdualstroval.aspx) are better than pods because at high speeds, the outer pods on each side gets more air versus the ones on the inside, it helps distribute the air more evenly. So I was wondering whats your take on this? I like the looks of the individual pods but if I could get better performance with the dual flange filters then I'll go that way.

Thanks,
James079



FYI
I'm building up a '77 GS 550 that I got a the beginning of summer and want to work on her during the off season.

Offline IanC

  • Administrator
  • Legendary Member
  • *******
  • Posts: 2119
  • Fast from the Past
Re:
« Reply #12 on: September 20, 2013, 01:36:22 pm »
It's not an issue you're likely to run in to. Quality pods, proper jetting/tuning and leaving the vent tubes off will solve any woes you'll encounter.
1978 Suzuki GS1000EC - Completely custom.
2012 Triumph Daytona 675R

Offline 8Ball

  • Mr. Clean
  • True Member
  • ****
  • Posts: 881
Re: Cheapo Pod filters....Why not?
« Reply #13 on: September 20, 2013, 10:28:54 pm »
Like Ian said, if you get your jetting right, and use quality filters that don't disrupt air flow, you should be OK on your bike.  (If you had CV carbs, it'd be a different story)

I still haven't got my jetting 100% on my GS550.  It's probably around 95% good.  For most people it would be fine, but I have a particular form of OCD that makes me crazy about tiny things.

BTW, that kit in the photo above is the one you want if you go with K&N filters.  The kit that is listed for the GS550  has four longer filters and the outer ones make hard contact with the frame.  The RC-0884 kit comes with two long and two short filters so the outer ones fit between the frame and the carb.
Quote from: jeff5150
just follow 129 on the map towards nc til it looks like a kid drawing it had a siezure
Quote from: Tomsljr
Know the difference between crack heads and Gap addicts? I have heard of people quitting crack.

I find a Soap Box comes in handy when getting on and off my High Horse!

Offline emd513

  • speed is an obsession. not a decision.
  • Legendary Member
  • *****
  • Posts: 2575
  • "adrenaline junkie"
Re: Re: Cheapo Pod filters....Why not?
« Reply #14 on: September 21, 2013, 02:46:45 pm »
What about bikes that are injected and not carb. Would it be a good idea to go with the dual mount filter or use the single pod on each be the same.

adrenaline rushing speed demon. insane? yes!!
03 Zr1000. Totalled
04 Zr1000. Traded
05 gsxr 600 under construction
Sent from my HTC6435LVW using Tapatalk 2
[/quote]

Offline IanC

  • Administrator
  • Legendary Member
  • *******
  • Posts: 2119
  • Fast from the Past
Re: Re: Cheapo Pod filters....Why not?
« Reply #15 on: September 21, 2013, 05:14:37 pm »
Honestly on F.I. bikes I would just put a K&N drop-in in and call it done.  Modern air boxes are pretty efficient and well ducted.
1978 Suzuki GS1000EC - Completely custom.
2012 Triumph Daytona 675R

Offline emd513

  • speed is an obsession. not a decision.
  • Legendary Member
  • *****
  • Posts: 2575
  • "adrenaline junkie"
Re: Re: Cheapo Pod filters....Why not?
« Reply #16 on: September 21, 2013, 06:53:16 pm »
Can't. Putting zx10 throttle bodies on mine and have to run pods.

adrenaline rushing speed demon. insane? yes!!
03 Zr1000. Totalled
04 Zr1000. Traded
05 gsxr 600 under construction
Sent from my HTC6435LVW using Tapatalk 2
[/quote]