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Positive vacuum? You mean...PRESSURE? Vaccum is a lack of gauge pressure, so pressure is what you want, right?

The exhaust is pressure, about the only pneumatic pressure and engine makes that has no use. Why would you need that tho?
 

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Discussion Starter · #3 ·
yea, pressure, lol.

To run my electric turbo I bought off Ebay.

Seriously now, I picked up ITBs from an R6. The secondary butterflies open with pressure, so its either find a pressure source, or find a way to make them stay open/remove them.
 

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You can always attach a small pneumatic pump that runs off 12 volts. The same kind they use to make vacuum for the brakes in electric convesion cars.

I would just delete them tho. And are you sure it's pressure, cause the dual runners in hondas run from vacuum. It's just a diaphram deep down.
 

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Discussion Starter · #6 ·
Its a 5/8" vacuum line, one per 2 TBs, and if you blow into it, they open... (great way to check, I know). I can't find what they attach to on the R6.

I could run solenoids or something of that sort, but it would just be easier to delete them...I hope, lol.
 

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rex2nr said:
Its a 5/8" vacuum line, one per 2 TBs, and if you blow into it, they open... (great way to check, I know). I can't find what they attach to on the R6.

I could run solenoids or something of that sort, but it would just be easier to delete them...I hope, lol.
Suck on it. I bet you they will still open. Sounds like its a diaphram and your blowing only opened it the one way.

I still say you should remove them. Why bother with dual runners on ITBs?
 

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Discussion Starter · #8 ·






Those are the ITBs. The "secondary" is a plastic plate which slides to the side, opening up the runner. Under that is the standard butterfly throttle plate which rotates to open. The large vacuum line on the left (in the second pic) is the line I am referring to. if you blow into it, the plates slide open, towards the line. Each line works 2 TBs.

Did I mention the Yamaha TPS works from 0-5V? And that the throttle control rod has the same thread as a CRX TB?
 

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Threads are standard. Normally they pick the cheapest (corse) one and since it's a Japanese company they both would run metric threads. I'm not surprised they match.

Sounds like you gotta alot of work to figure it out. Have you sucked on the hose to see if it opens?
 

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If you can blow into the tube to make the parts move, it doesn't take much air pressure... I've never been able to register even 1 psi by blowing into a gauge. Here's a thought... Maybe the positive pressure you need is normal atmospheric pressure. That slide might be acting as a venturi, creating a slight negative pressure on the opposite side of the diapragm that moves the slides. The reduction in pressure would make atmospheric pressure seem positive, causing the slide to open. The more air flow, the stronger the venturi effect and the further the slides open. It might be designed to help with the all-or-nothing tendancies of ITBs when it comes to throttle control.
If that's the case, those tubes should be hooked up to a filtered air source... But then, why the plastic fittings with screens?
 

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Discussion Starter · #13 ·
I'm kinda suprised that the diameter of the two throttle arms are the same. I would expect them to be metric, but I thought the bike's would be a bit smaller.

I'm not sure, but when I did suck on them, it had a strong oil taste.... which has me wondering if they ran to the PCV. Or, it just requires much stronger of a vacuum than lungs can create. If I force them open, air escapes around them, and a slight amount does come out of the lines. I guess I need to pull them apart.

The fittings have 2 screens, one at the bend, and the other at the base of the connector, which you can see in the picture.
 

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Poked around on an R6 site out of curiosity. The service manuals are of little to no help. One image I ran across in a how-to post:

I just can't tell exactly what's going on there. That's looking down from above the bike at where the airbox would be (it's been removed) The two big tubes at the top of the pic are intake ducts; the two smaller tubes just below them I think are what we're looking for, though the plumbing below that makes it hard to tell what connects to where. They just get filtered air AFAIK.

[edit]
Here we go:

One tube and fitting on the right, the other is being held back by the photographer (the bright blur in the lower left)
In a different thread, a pic showing the innards of the airbox, less the velocity stacks:

You can see the two holes for the air connections just on the other side of the divider. I guess those screens are there because they're getting unfiltered air:

Ahh, nothin like using other people's bandwidth. ^_^
[/edit]
 

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haha, its funny to see how kids these days have no idea how motorcycle carburetors work! :lol: just kidding.

Those slides are on all motorcycle carbs. They are either CV type or non-cv type. Non CV type uses a flat slide that lifts manually as you controll the throttle. CV carbs use a pressure differential to raise the slides a certain distance, which corresponds to the demand of the engine for air, and fuel as well. Under the slide cap, the slide has a sort of a hat section. See if the following diagram makes sense:

__ __ hat portion
...| |
...| | slide
....|
....| fuel metering needle

The underside which sees airbox pressure (ambient) (this is the one you've likely been blowing into) and the top of which sees vacuum. This when you open the butterflys, the flow of air increases in velocity, creating a stronger vacuum by using the venturi effect. So the top of the "hat" sees vacuum compared to ambient pressure of the airbox. This draws the slid up and also draws up the secondary fuel metering needle, delivering more fuel into the mix. So, although i haven't looked at a set of carbs in a while, That tube would likely go into the airbox.
 

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Discussion Starter · #19 ·
I wish I've been able too play with bikes... too many people are worried I'd kill myself or something along those lines :rolleyes1:

Bas: I am going to cut the runners from an A6 manifold, and use silicon tubing with hose clamps to attach the TBs. Most of the bikes I've researched have them attached this way. Also, I would have to drill and tap holes into the R6 TBs to even think about bolting them up. Using the A6 manifold allows me to use OBD1 injectors, with a Z6 fuel rail to keep fuel delivery as simple as possible. Also, if they don't work, or preform the way I'd like, then I can just swap over the the Z6 manifold.

Ok, so those lines attach to the air box, so I could just leave them open, or I could build an airbox, which I've been thinking about.

Wow, this thread has progressed pretty far from a stock question... maybe we should move this to the mod garage? Mods?
 

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Mmmmm, i haven't really studied, or sat down and thought about the fluid dynamics, but i think there may be reason of having them plumberd into an airbow of a given volume based on the flow requirements of the engine. Hmmmmm, good question though.
 
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