CBX "Air Tees"

[Randakk]

I get lots of questions about these.

They have nearly zero function, but if you're doing a concours level carb restoration , you may be interested in these beautiful reproductions I've sourced from from Germany:



Details here: http://www.randakks.com/CBX%20Page.htm#4

[alimey4u2]

Certainly look well made ....

[EMS]

I saw some repros a while ago where the tees were actually metal. This would mean you would have to break the bank of carbs to install them.
I haven't tried it myself, but I know guys have installed new rubber tees without taking the carbs apart.

[Randakk]

I saw some repros a while ago where the tees were actually metal. This would mean you would have to break the bank of carbs to install them.
I haven't tried it myself, but I know guys have installed new rubber tees without taking the carbs apart.

Correct. These reproduction "air tees" can be installed without splitting the carbs apart. I've done it myself.

Takes patience, good lube, good light, some "pick" tools and a serious reward libation after the task is competed!

[big al]

Yep, my mechanic at Apex Sports here in Colorado Springs managed to get them installed in mine not only without splitting the carbs, but with the carbs on the bike. (It was worth two 6-packs of Fat Tire!) He was of the opinion that they ABSOLUTELY have to be there, but it didn't solve the "why won't this idle" question.....

[Mike Nixon]

As Randall indicated, they are not necessary. They have absolutely no performance impact. What they do is essentially keep water out of the carburetors by allowing the bowls to vent to atmosphere but indirectly through a hose to shield stray material from getting in. I have run for over 50,000 miles on my own bike without any tees. Randall's German made tees look very close to the stock item and are apparently quality units and indeed at a good price.

I also sell air tees, of a different configuration, one that is better in my opinion because unlike the rubber based stock and aftermarket ones will not rot out and unlike the aluminum aftermarket ones 1) looks stock, 2) fits properly, and 3) having no rubber will not rot. They are also, unlike all the others, one-piece. Noting to separate, come loose, shift out of alignment, etc. However, like the aluminum ones the carbs must be disassembled to install. Depends on what your goal is, I guess. Shameless plug number 11. :) Please don't think I want to take anything away from Randall's product. He deals only in quality stuff, being a quality individual himself! :)

[big al]

My "highly schooled mechanic" put em in so they block the sync screws. Oh well, carbs are out (again) so I can move em around.....

[Mike Nixon]

Seen folks do that too. The notches in the steel steady plates seem to some people to be for the vent hose. They're not of course. They're for the synch tool. :) By the way, Al, you should have asked. There is a way to move them into correct position without removing the carbs.

[big al]

Oh, absolutely, I think if I just unscrew the top racks, point the tees down, and put the racks back on I'm good to go. I have the carbs off (again!) to quadruple-check my float levels and make dang sure there are no obstructions in the pilot circuit anywhere.
Same mechanic, btw, was of the opinion that's it's way lean, and that's why it won't idle, and he suggested getting rid of the Dynojet Stage 1 needles & putting the stockers back in. So I grab my trusty digital caliper, and the end measures:
Dynojet needles 1.26 mm
Stockers 1.68 mm, which would lean it out even more. Anyway, how much do needles affect idle? Just OFF idle maybe.
So I'll check the pilot circuits AGAIN, my float levels were probably TOO low 'cause I was having leakage problems. Might be closer than i think to ironing this mess out!
Thanks Mike. Any ideas from the carb guru on this one???

[Mike Nixon]

I don't know who the carb guru is, but...Dynojet kits work in some bikes such as ZXR12s, GSXRs, various others. But they don't work in CBXs. Not only do you dump gas into the carbs, but you get no return for it. Having said that, I don't think your leanness, if that is what it is, has anything to do with the Dynojet kit. But leanness is extremely common on CBXs, mainly because their idle circuits require the patience of Saint Francis to get clean all the way. When the average person thinks they're clean, they're maybe halfway clean, I can practically guaranty it. A second effort gets them a little further. Not until they resolve to making cleaning the idle circuit a sit down and do it until it is absolutely right job, no matter what or how long it takes, do they get anywhere. I probably spend 4 hours just on the idle circuit on the carbs I do, and I have been doing them for a very long time. And when I say "circuit," I don't mean just the idle jet, although that part is hard enough to get clean. I am quickly becoming a believer in yanking the pressed in jets as a matter of course, just to save time. The idle circuit also encompasses the aircut valve, the pilot screw openings and cavities, the bypass passages and outlets, the whole deal. The only thing close to as much work as getting the idle circuit to work properly on a CBX is getting the accelerator pump circuit to work properly on the same bike! :) It can be a pain. I have developed special tools just to massage this one circuit, it is so important to how the CBX carbs work and work right.




I would definitely recommend stock jets. If a 79 with the airbox, no matter what pipe or replacement air filter element, I would go with stock secondary mains and 72 primary mains, idle mixtures 2 1/2 turns to start, and that is it. 80s with stock airbox, again, no matter what pipe or replacement air filter element, shim the needles 0.020", idle mixture screws to 2 1/2 to start, and that is it. 81/82 in the same configuration as above, I would leave absolutely stock except for the idle mixture screws at 2 1/2 turns, which isn't a modification anyway. :)

By the way, another problem with Dynojet parts is the needles (at least the early ones I have dealt with) are brass and very wear and breakage prone. The stock needles are very durable non-wearing beryllium.

[big al]

Thanks for the reply, Mike! (I'm referring to YOU as the carb guru, btw!)
Interesting tools, and since I own more than one of these babies, I'm curious about where I can procure a set, and, once you extract the pressed-in pilot jet, can you actually re-use it or does it need to be replaced?
Also, on the Dynojet kit, all the DJ parts are in the carbs, and the slide holes have already been drilled. Would it, at this point, be worth my while to fiddle with this and make it work? I have a set of stock needles I can stick back in there, but how's that going to work with the drilled slide holes?

Sorry for the "question overload..." I've been fiddling with this thing for MUCH longer than I thought I'd have to. I've done carbs before with great success, but on a bike with a lot of "known" factors.
THIS one I've been restoring, and it's the first time I've even had it running.

Sure appreciate all the info!

[EMS]

Thanks, Mike, for taking the time to "chip in". I don't think anybody here could have done it better. On behalf of all members on the site:

[Mike Nixon]

Thanks for the reply, Mike! (I'm referring to YOU as the carb guru, btw!)
Interesting tools, and since I own more than one of these babies, I'm curious about where I can procure a set, and, once you extract the pressed-in pilot jet, can you actually re-use it or does it need to be replaced?
Also, on the Dynojet kit, all the DJ parts are in the carbs, and the slide holes have already been drilled. Would it, at this point, be worth my while to fiddle with this and make it work? I have a set of stock needles I can stick back in there, but how's that going to work with the drilled slide holes?

Sorry for the "question overload..." I've been fiddling with this thing for MUCH longer than I thought I'd have to. I've done carbs before with great success, but on a bike with a lot of "known" factors.
THIS one I've been restoring, and it's the first time I've even had it running.

Sure appreciate all the info!

Not a problem. All the holes are for is to theoretically (actually works some times) make the slides raise at a faster rate than stock. This is not always desirable. It is simply a way to make the stock CV carbs behave more like mechanical slide units, which, again, isn't that good an idea on a street bike in my opinion. At any rate, a lot of folks have gone back to stock needles with good results, enlarged slide holes notwithstanding. Don't forget that you must chase down that lean condition as a separate issue not related to the funky DJ parts.

The tools are custom made. I have considered making more but they're time intensive. Folks on this board have recommended ways to remove the idle jet using a machine screw. That works. Yes, the jet can be replaced if it does not show any evidence of aluminum "tearing" on its surface. It only goes in a couple mm so galling or tearing of the aluminum carb body isn't that common. So yes they can be reused. Clean them up good. Wire stroke them. Make sure the hole in the jet is perfectly round.

[Mike Nixon]

Thanks, Mike, for taking the time to "chip in". I don't think anybody here could have done it better. On behalf of all members on the site:

Thanks. :) In reality, nearly everyone on this forum has said this same thing, in more or less the same words. I take no credit for being master of the more or less obvious, and especially that already repeated numerous times.

[alimey4u2]

Couldn't agree with EMS more, thanks for the support Mike...