Airbox vs. Pods

Hey folks:

I'm wondering if anyone can advise me on removing my airbox (82' XJ750) and changing to pods. I want to use a set of UNI-foam pods that I have sitting around.

All my Suzukis are "podded" with K&Ns. However, all my Suzukis' are also re-jetted.

Has anyone had any success with simply removing the airbox and going with foam-pods (without having to purchase a jet-kit)?

 

It will lean out really bad without rejetting, and from what ive seen people have alot of problems getting them jetted right with pods.

 

You can guarantee that you'll need to rejet by switching to pod filters. WAY too much airflow for the stock carb setup.

 

You can do it but there is the catch. You will have to rejet and then continue to tweak jet sizes and air/fuel ratios until you get it happy again. A long and arduous process requiring the removal and installation of the carbs a few to a bunch more times. And remember, this will get you some power gains but you will pay for it from somewhere else, such as power loss in the low end and so on. Additionally, you run risks of problems if you get caught in the rain or run through a big water puddle. And pods will not give you their full potential unless you get the exhaust freed up as well. You should perform the upgrade as a set, not piecemeal or you have to go through the whole process all over again.
You make the call.

 

My bike (seca 750) came with pods, and some non-mechanic swapped in 118 ' s for the factory 120 ' s , and I have a 4 into 1 pipe that's a little noisy. I should have 122-124 ' s.

My bike runs a little flat at full throttle, but very drivable on the low end.
I'm at sea level + 100 FT. There's an odd chance my 118 jets are "drilled" but I didn't inspect them with a microscope.

 

The Hitachi Carbs are designed to share the combined Intake Air through the Airbox Opening Inlet.
I don't know what Cubic Feet per Minute they are designed for ... I DO know that they share that Intake Air.

Pods add so much more air to the equasion that its impossible to know, with any degree of certainty, how much more Fuel is needed to make them perform well without the shared Intake.

There are some guidelines to follow but the end result is having the Carbs rigged to force them to respond to the additional air brought-in without the stock airbox.

Very few people are 100% satisfied with the results of re-jetting and experimentation to MAKE the Carbs work within the new Air Flow measurement using Pods.

I have never been successful in the ability to rearrange the jetting and tinker with an engine that has Pods and not its stock airbox.

So frustrating did it get for me that I have abandoned working-on and giving advice on how to make an engine run good with Pods.
There's just too much air to deal with and not any way to regulate the Mixture to provide real tuning throughout Idle and the Power curve.

Even with the popular Kits available, some sacrifices have to be made in the performance of the bike.

Pods look good and are very sexy looking on the bike.
You pay the price for vanity in the inability to get the bike dialed-in and running very well throughout the whole range of performance.

 

One of are members has switched to pods and running a open exhaust and he did not rejet.

 

It's a safe bet that engine won't be lasting very long.

He's going to be running way too lean and end up burning piston.

 

I was planning on podding the maxim I'm taking to Europe with me until I read all of the postings regarding it. Your reliability goes out the tubes in wet weather and any performance gains you may get after countless hours of tweaking just don't seem worth it.

That being said I will do my Seca when I get back, cuz it is a cool look. Who needs reliability when you look good.

 

You'll be glad you didn't put-on the Pods before shipping the bike overseas to do some touring.
Europe has some challenging terrain to deal with and loads of Mid-range Cruising.
The Pods would have put you at a serious disadvantage trying to keep-up with traffic on ascents and open highway running.

Adding them because they "Just look good" isn't a wise choice. I'd rather be able to crank-it open and get down the road than look good puttering-along because the engine isn't tuned efficiently.

Your call!
Get the bike dialed-in for the tour and you might find a new respect for running well that you won't genuinely experience when you abandon the airbox and add-on the Pods.

 

One thing to consider. If you just like the look but don't want to deal with the excessive airflow. Perhaps you can put some restricter plates on the carbs when installing the pods. Granted you would still have some serious experimenting to do, in order to determine how much restriction is needed to keep the bike in tune. But it would still be a lot less work than taking the carbs apart multiple times for re-rejetting. Perhaps someone could do this and pass the information on. I could see some simple plates made of aluminum with the right amount and right size holes drilled into them working just fine. Just a thought.

 

In theory ... a good idea!
In Practice ... not so good.

The Rubber Boots which connect the Airbox to the Carbs are designed to act as Velocity Stacks.
They form the incoming air into a compact column of air that enters the Venturi and gets further compressed and accelerated to cause a pressure variant above the Emulsion Tube facilitating the drawing-up and into the air stream of the Main Jet Fuel Supply.

One of the factors that is not easily overcome is operating the Carbs WITHOUT a Velocity Stack.
Absent a Velocity Stack, the Intake Air is turbulent. The turbulence of the Intake Air and the close proximity of the turbulent air to the Emulsion Tube opening contributes to the Lean condition so difficult to overcome.

The design of the "Restrictor Pod" would have to include a tubular "Stack" to aim Intake Air at the Center of the Venturi.
The "Stack-add Pod" would have to have a tunable Intake Air orifice that could be widened or narrowed as needed for the Fine Tuning.

That ... plus an Oversized Main AIR Jet feeding atmosphere to its surrounding cavity around the Emulsion Tube would also be a benefit.

As would increasing the Air Metering Ports on the Emulsion Tube to allow for MORE Air to enter the Emulsion Tube, particularly its Mid-range Openings and Wide-Open ports near the top to answer the need for increased Fuel Levels to the Main FUEL Jet Supply at Mid -to- Wide Open Throttles.

The Turbulence factor is not likely to be overcome unless Velocity Stacks are somehow added to the Carbs Main Intake Opening.

 

He's talking about me. I'm not running lean as verified by both the performance of the bike and the color of the plugs. When you're ready to make that bet, look me up. I've been with this setup for over 4000 miles with *ZERO* problems.

 

So does all this extra airflow come into effect with a 4-1 exhaust and stock air box with a drop in K&N filter? How about with 4-1 and stock filter?

 

Thanks for input folks.........I have probably "podded" and "jetted" some twenty different bikes. However, I have never used the UNI-foam pods that I am considering.

These foam pods are much more restrictive than the K&N or EMGO pods so whether I'll have to rejet or not is to be seen. I don't think I'll have to.

Ain't it a gamble though, man I hate to have to cut the airbox to remove it. . The main reason I always opt to remove the airboxes from my machines is access to the carbs (although they do look cool). It is so easy to work on the bike with the airbox gone. Trully, I have never noticed any huge boost in performance from podding and re-jetting. In fact, I believe I lost a bit of low-end torque on my GS1100E (gained some power on the upper-end; but I rarely ride my GS1100E in its' upper-end; I have kids and a brain).

 

I sell pod filters. I have plenty of them in stock, UNI, K&N, Emgo brands.

I suggest that everyone read the advice of dtkid above very carefully.

 

Hey all, New guy here. I have a 81 xj650 and I've been riding the bike for 2 years now, I'm not a wrencher, so forgive me if I say something stupid. The bike has been running great but I noticed that the rubber stacks that connect the air box the the carb. in not connected, so the carb. is not pulling air from the air box, there is a 1/2'' space between the rubber and the air box, now the bike still runs good. I have pods, culbman bars, exhaust wrap, and a jet kit I got with the pods from speedmoto company, after reading all the post about bikes running bad what would you suggest I do, I'm a little stumped any help would be greatly appriciated. Thanks in Advance

Rev

 

Ride over to Billerica and we'll tune it up once.

Easier to try and tune it up stock ... than to put-on Pods and start the dancing around with rejetting.

I think you should give me a shot at syncing the carbs ans adjusting the Mixtures with my Colortune Plug before doing Mods that are going to require more work and jetting.

 

Good luck with that. I hope you don't fry a piston.

However, you won't know for sure whether or not your running too lean until you put it on a dyno with a sniffer.

 

well guys...my stock airbox is bad news...and Im going to go with pods....I plan on getting a colortune plug, but I want some pods that if i do hit some rain I wont be on the side of the road....instruct me through this guys....plus I just dropped my engine back into the bike...if I did get an air box...i dont want to go through the trouble of putting it in....