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Discussion Starter #1
Well first off hello and Merry Christmas to all!

As some of you know I finally got my beloved cl350 up and running right before the weather turned, and while it does run pretty good I want it running great when spring time comes around.

So, in addition to picking up some main and pilot jets to experiment with, I've been eyeballing this carb gauge set:

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=330511019342&viewitem=&sspagename=STRK:MEWAX:IT

It's an EMGO product, I believe. I see them for sale everywhere but this is the cheapest I've seen it offered.

But will it work with a set of Mikuni VM carbs? The listing refers to it as a "vacuum gauge" set -pardon the ignorance, but do the carbs in question need to be vacuum type carbs for this to work?

Thanks in advance
 

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I don't see enough there to make those useful on a two cylinder engine having individual intake runners.

You'd be better off using plain vinyl tubing and colored fluid of choice.

Mercury first choice, many use atf, some use colored water.

Study mercury gauges and you'll see they are merely tubing with a scale.

Those gauges would require tiny metering orifices and/or a damping accumulator to obtain anything useful from them for ir applications.
 

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Those come with little plastic valves to put inline to act as an orifice/damper. They work ok but the Gauges don't always repeat -
 

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The problem is that the aneroid chamber is a fixed size.

It isn't possible to dampen the violent pulsations and have anything resembling accurate for a broad range of engines.

Save your money and make your own using clear hose and colored juice.

Secure them to a board with fixed increments marked.

Calibration is easy enough.
 

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HackA is right. Google "home made manometer" or variations of it and you will find some how-to's. It is easy and fun to make your own that will be more accurate than cheap gauges.

Ken
 

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Scrap the shitty green valves that come with those and get some drip irrigation valves( http://www.dripirrigation.com/drip_irrigation_info.php?cPath=35&products_id=65&osCsid=6b1boipfmhrmp55crme0ssk735 ).
Then you'll need some way of getting to the manifold side of the carb:
http://www.mcmaster.com/#barbed-hose-fittings/=aal3np
Drilla hole inyer manifold and plug the coupling in.
Calibrate both gauges by hooking them up to the same vacuum source. Hopefully they will read the same.
Then have at it.
To dampen the pulses, just dial down the valves till there is just a little flutter. It goes away once rpm's go up.
Gauges work best for me. They help you see if one side of the splitter/cable ass'y is hanging up. Plus it's just funner to watch 'em.

NE
 

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just stick a 25 pilot jet in first couple of inches of tube, it damps out pulses (as recommended by Suzuki when setting up TL/SV1000)
 

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Do ya think the same size jet recommended for a 500cc cylinder will be best for a 175cc cylinder?

I don't.

Regardless, I dig my mercury gauges and manometers.

They are indeed far more useful and less fussy than chambered analog vac meters.
 

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Mikuni :D
Hack, it doesn't matter, it's to damp down pulses.
The restriction will allow the main length of tube to act as a plenum, vacuum may build a bit slower but it will still be vacuum.
You need to stop sniffing mercury vapor, it's making you crazier than me [8D]
 

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Damn, now I'm crazy to go along with incomprehensible.


I certainly grasp the concept of the jet and merely posed a rational question.

Is the same orifice that is optimal for a 500 cc engine also optimal for 175cc's?

If not should the optimal jet for the smaller engine be larger or smaller than the previously prescribed jet?


Colored water or atf in clear hoses truly are far less fussy and provide a much more comfortable and useful visual interface.
 

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I have a 2 line home made manometer with no damping jets. I use fork oil and in it and it's never been sucked into any engine so far (mind you I have about 12' of tube in the set-up).

Only cost you a few $$ and is really accurate.
 

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Hack, doesn't seem to matter, anywhere from 25 to 45 seems to work OK, bigger jet allows a little more 'flutter' with a 500 cylinder
 

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Discussion Starter #14
Okay, you've sold me on the idea of making my own manometer. Looks like a fun little mid-winter project. But surely you guys have photos of manometers, mercury gauges etc. that you've built, and are just dying to show off your ingenuity....right?
C'mon, photos or you're all a bunch of blowhards that don't know what you're talking about and have never actually built such a contraption!;)
 

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There used to be instructions in the back of every clymer manual on how to build your own manometer. I think they stopped doing it because people didnt understand how to grasp the concept of making your own tools.
 
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