Good news about "pods"

@TimeToRide

Enlarging the vacuum port or reducing spring resistance has that effect when the carbs are operating normally. Because the vacuum will be stronger or the spring will be weaker allowing the slide to raise faster. When the slides aren't operating normally because of low +/-, it will allow them to function properly. Get the lift that is needed.

 

Hold on now. This thread was started, according to you, because you had "good news about pods."

Apparently that isn't the case. What IS the case is that you are waist deep in the "trying to do" phase, like so many others before you for the last umpteen years.

What Rick is trying to do is explain some of the SCIENCE behind what it is that you are trying to do and why you're seeing the issues you are.

Comparing the attempts to make pods work on a four-cylinder, high revving motor with 4 CV carbs to the fitting of a "pod" to a single CV-equipped, low-revving twin is evidence of the fact that you don't fully understand the science behind what you're actually up against.

Rick is just trying to explain the battle you're having and why you're still having (and will continue to have) it.

Be sure to let us know if you actually do succeed. Because, despite the optimistic title of the thread, it sounds like you've got a ways to go.

 

8O :? :lol: :twisted:

 

Interesting thread.....

You would think that the solution would be to add more fuel to remedy the lean condition (rejet, shim needles, pilot jets,etc). However, Rick and others have pointed out in the thousand threads before this, this lean condition is not caused by the failure or amount of fuel delivery (tuning, sync, blocked passages, etc). Instead it is caused by the poor vacuum condition that the pod creates. This poor vacuum does not allow for the proper amount of fuel to be sucked into the chamber or the proper atomization of fuel to effectively combust. Re-jetting + shimming will only increase the amount of improperly atomized fuel.

Look at my bike. Yes it runs and rides nice. However, it is a b***ch to start (improper fuel/air ratio), lean - no matter what I do to it (too much/too turbulent air), backfires (improperly combusted fuel), and when it's good + warm, it want to idle @ 4500 rpms (hanging slides due to improper vacuum)

When you or someone else finds THE ANSWER, please let me know! Although, I doubt it's gonna happen, unless maybe you would stick Fitz, Robert, Rick, and a few others in a garage for a month or so. Someone told me this a long time ago - not in relation to my bike, but it certainly applies here.... "A team of engineers with years of experience in this area designed this over the course of months, and you think that you can do better than them in an afternoon w/ a case of beer? I think not."

Cause I gotta agree on one thing... anything looks better than that clunky hunk o' plastic stuck in there. I do agree that appearance is important, but it's not everything. Every Harley owner I know will chrome anything and everything (i bet that they would chrome the tires if they could). But you know what? It's all cosmetic. Ask one of those guys to make a mod that will damage the bike in the long run, and see what they say.

Now if you'll excuse me, I have an airbox to put back in.

 

I like my airbox but I was reading on other website that if you put an extension of 2 inches in between the pod and the intake of the carbuarator that makes the turbulance go away and will run good. I think is worth to try.

 

This makes sense as it would help to reform the air and may help restore the propper pressure around the main air vent. I have seen some have success running the stock intake boots on their pods which is what I plan on trying when my dynojet kit comes in.

Cheers
Dave

 

Just as a note to the curious, my bike runs fine. It idles at 1200, goes thru all the gears, fast throttle, tan plugs at idle and mid range, and gets to the bottom of the speedo in 3rd gear. I could easily leave it where it is.

Update: Checked plugs @ WOT and they are tan, too. All the action just takes place at the front half - 3/4 of the throttle. Not something I noticed until people started talking about airflow and WOT after my post on chasing the lean condition that I realized was weather related. Afterwards, I took my bike out and checked it out. That is when I started looking into all these +/- pressure scenarios.

 

SOUNDS GOOD!!!

skillet

 

Update:

Not good news. Clipping the springs only allowed me to get to 3/4 throttle. Save your springs and do not get into drilling the slides unless you're adventurous.

3/4 throttle was the best I could get. Slide and spring altering together MIGHT find what you are looking for, but slides are expensive and JB breaks down in a constant environment of gas. Hard brittle pieces are not advocated in carbs or engine.

As I said before, podding 550s is a pandora's box. It's an adventure you must wage yourself. You could listen to people that have come before you, but who does that?

My setup is at sea level, with east coast humidity and an average 85 temps, it ran fine with stock springs, only the throttle was condensed to within half. Not noticeable if you're not looking for it, because it behaves as any other bike would. Just more sensitive throttle.

I had everything you want in a bike. Just not WOT. Hit me up with a message if you have questions. I learned a shit load about tuning these carbs as far as jetting goes. I'll help if I can.

Four spacers on the needle
137.5 main jets
hand tuned air/fuel

I do believe that the fuel makes up for the lack of vacuum. I could almost watch the needle go down.

All stages had tan plugs. Idle, mid-range, WOT

This held true at the lowest spring level, but it still registered as a rich environment, due to the false lean condition created at WOT due to the lack of vacuum.

I also adjusted the valves, synched the carbs and they are clean. It's not impossible to run them, but your bike has to be straight to even touch the carbs.

I've pulled the carbs so many times to adjust, I could do it in my sleep. I'm tired off chasing. It gets old. Especially with such a small window to find.

 

love it

 

And just to reiterate... I posted a video of my bike running, idling, revving etc. perfectly YEARS ago with pods and open exhaust. Now, approaching 25k miles later, it's running just the same. Surprise, no holed pistons, no backfiring, no misses or crappy acceleration, pulls strong through the entire power range straight to top speed. (id say redline but do not run a tach) My video has been reposted many times by others, but seems to get overlooked by the non believers.

P.S. I love stirring sh!t, and it's even better with video evidence to support my claims. Pods4life

 

im new to all this and now have an 82 xj750 rj and i'm restoring/modding it. but i was thinking, what if you put a shield around the pods, all of them.

basically have 1 oval piece of sheet metal mounted around all the carbs? I'm not too sure on what length it would need, probably a good point to start would be the same length from the base ot the pods to 1/4 in past the top of the pods.

would this create enough vaccum evenly for all the carbs to run the same?

 

There was a member (from England I think) that did something similar. His wrapped around the sides and top to about 1/4" from the ends of the pods. He only posted a few times and then dropped off. He never said anything about the tuning on his scooter...

skillet

 

bummer, i would imagine that it would have to help somewhat, cause your giving all the pods a central area for breathing

 

I was thinking about adding restriction and using the velocity stacks from the airbox.... w/ a combination of re-jetting..... my bikes way too lean + getting sick of too much downtime.... put my airbox back in.... maybe someday i'll mess with it again....

 

Update:

I took the front half of my air box, that I had held on to after cutting it out, cleaned it up and trimmed a little so I could get it back in without pulling the engine (had to still remove the starter). I installed stock springs and went to two shims at needle and kept the same main. Since this was an experiment I left it open at the air filter intake. Gave it a test run and had full throttle again. Checked the plugs and at mid and WOT they were a very light tan. Took it home and attached the stock filter with a thick bead of silicone. (I didn't really care if it would be a hindrance in the future, since silicone is easy to clean off and a filter is cheap, and would be better if the foam was gone. Then a mod could be done to make a better mating surface.) After that I went for a ride with the filter attached, the plugs were a perfect tan throughout the power band.

That was the first time I had to reinstall the carbs with the intake boots. :evil: OFMG! I am still thankful it worked, because I would rather rebuild an engine than wrestle with those carbs and a stock air box again! I don't know how you purists do it! God bless you!

The end scenario is that I still have the performance that was my ultimate goal in the first place, but it took the front air box chamber to allow the carbs to function. I don't regret anything, because I learned so much about motorcycles during this process. Had I not won those NOS MAC 4 to 1s for $30 on EBay in the first place, I wouldn't have opened this pandora's air box. I would still be an owner and not a mechanic if I hadn't though, so I cherish the entire experience.

I still love working on the bike in one way or the other even though it runs fine and looks good, because what do you do after you work on it? Ride it? Lol!

 

So after all that, the "good news about pods" turned out to be "put the airbox back in?" (The front half of it anyway.)

The front of the 550's airbox has this suction tube: http://xjbikes.com/Forums/viewtopic/t=31872.html Did you eliminate it, or put a new filter in it?

 

Ah, yes! Couldn't help yourself, could you Fitz? (Redacted)

The air box had everything as it did stock. The only thing missing is the filter enclosure.

(Redacted)

(Redacted)

 

Nobody's being a prick.

You proclaimed "GOOD NEWS about pods" and I've been waiting to find out what the solution is; I have a couple of friends who are STILL struggling with them and I'm unable to do them any good. I'm open to suggestions, and yes, I've indeed read the entire thread.

I was HOPING maybe somebody did actually have some "good news." Unfortunately, you've seemingly learned the same lesson as the rest of us-- ain't no "good news" to be had.

You've proven it again; I didn't do anything except hope for some "new news" that didn't happen. The "fix" was reinstall the airbox, so no progress has been made in regards to pods.

Not trying to be a prick; just callling it like I see it. 'Twarnt no "good news about pods," you ended up putting your airbox back in.

 

I didn't bother to read your response Fitz, but I apologize for blowing up at you. I feel bad about it. You are an expert on our bikes.