Carb synchronizing question on a 1979 GS750

[earlfor]

Only during that portion the bit is above the tangent of the radius, but if that is a concern, you can flat spot the area with a dremel and 1/4" grinding wheel, or a couple strokes with a small file.

Earl

You dont need a flat spot. Drill a pilot hole with a 1/6" bit

Drilling into a radius (curved surface) results in an elipical (oval) shaped hole. You can then tap that hole and you'll still have an elipse. It may work if you use a sealant around the fitting when you screw it in place.

~Adam

[stiksave]

One more question. If I have an automotive vacuum gauge And I read the first value, couldn't I do each one individually? Just being cheap.

Siksave

[earlfor]

Technically, yes you could do it that way. BUT, there are 4 vacuum ports and when you check vacuum, none of them can be open, so you would have to cap the ports off and switch back and forth changing caps. also, when you change the vacuum level on any one carb, it will change the level in the other three. Thats simple enough, but the problem is it will not change the level by the same amount in each of the other three. so for example if your carbs 1 through 4 have vacuum levels of 20 cm hg, 10 cm hg, 30 cm hg and 20 cm hg and you start with carb #2 which had 10 cm hg of vacuum. If you raise the vacuum to 20 cm hg in carb #2, it could/would change the vacuum in carb #1 to 15 cm hg. You set carb #2 to 20 cm hg. Carb #3 is now 40 cm hg and carb #4 changed to 10 cm hg.
all this because you changed the value on the #2 carb. It can still be done, but you will probably be retirement age before you get them all set to equal values.

Earl

One more question. If I have an automotive vacuum gauge And I read the first value, couldn't I do each one individually? Just being cheap.

Siksave

[stiksave]

I'm almost retierment age, so forget that idea. So I guess I'm old, and old school. If you look at some of the commercial setups, all they are is a board with 4 vaccum gauges and hose and adapters. The motion pro is a vaccum monimitor. I use monimitors at work and other pressure type gauges. I know that the cost of a simple 30# pressure gauge is minimal. So if vaccum gauges of the same quality could be dug up, couldn't I make a 4 guage pro setup. Playing with mercury and glass with my kid around sets off an alarm for me. Like a $50 one time use Motion Pro.

Just a thought from an old guy who's done everything himself restoring my Suzy. Why not make the tools to keep her purring?

[earlfor]

yes, you can make your own using 4 vacuum guages. The biggest drawbacks to vacuum guages are they are more difficult to read accurately from a distance and you will need to calibrate them to each other each time you use the set. Considering the cost of buying four of them. I think the better choice is to spend the bucks and buy a Morgan carbtune II. It does not use mercury, but instead uses four stainless steel cylinders, requires no calibration and is easy to read. Accuracy is superb!
The downside is the four guage tool is about $80. Upside is John Morgan is a great person to deal with and he stands behind his product. Parts and service are available. I ordered mine direct from him in England.

You could also use water tubes instead of mercury. But, you will need a rather tall instrument for a column of water equivalent. :-)

Earl

I'm almost retierment age, so forget that idea. So I guess I'm old, and old school. If you look at some of the commercial setups, all they are is a board with 4 vaccum gauges and hose and adapters. The motion pro is a vaccum monimitor. I use monimitors at work and other pressure type gauges. I know that the cost of a simple 30# pressure gauge is minimal. So if vaccum gauges of the same quality could be dug up, couldn't I make a 4 guage pro setup. Playing with mercury and glass with my kid around sets off an alarm for me. Like a $50 one time use Motion Pro.

Just a thought from an old guy who's done everything himself restoring my Suzy. Why not make the tools to keep her purring?

[stiksave]

For the sake of discusion. A U type monometer reads 12" water column. Is marked from behind, at "0" half way up the U,and 1" thru 6" above and below. When reading, the sum of both sides are added. So basicaly it's only about 14" high. It would read either way, pressure or vaccum, if my old brain isn't failing me. These also could be mounted as a foursome as a gauge set. Calibration can be done by moving the measurement display or adding or subtracting the fluid in the gauge to zero it out at rest. You would eliminate the mercury. We use a 50 50 antifreeze mix, but anything that's a bit more consistant than water. Just a thought.

Stik
8)

[earlfor]

Or you could "calibrate" by having excess tube length and allowing more or less length of tube to lay flat at the zero point. The principle also works well for finding two points 50 feet apart (or any distance) that are at exactly the same height. Its a lifesaver for building a deck all the way around your house and having the two ends join precisely in height. :-)

Earl

Calibration can be done by moving the measurement display or adding or subtracting the fluid in the gauge to zero it out at rest. You would eliminate the mercury. We use a 50 50 antifreeze mix, but anything that's a bit more consistant than water. Just a thought.

Stik
8)

[stiksave]

Can one of the math geniuses convert cm to inches water column. I'm looking at magnihelic gauges that read inches water column. They can be set to read either pressure or vaccum. I told you I was stuborn. Cm stands for ? :roll:

Thanks,
Stiksave

[earlfor]

cm is centimeter. 100 cm equals 1 meter. 1 meter equals 39.37 inches

1 cm equals .3937 inches

2.54cm equals 1 inch.

Earl

Can one of the math geniuses convert cm to inches water column. I'm looking at magnihelic gauges that read inches water column. They can be set to read either pressure or vaccum. I told you I was stuborn. Cm stands for ? :roll:

Thanks,
Stiksave

[Anonymous]

Home Made Manometer

Here is a linke to one of many threads about home made twin carb/throttle body sync tools on a BMW site I frequent.

http://bmwsporttouring.com/ubbthreads/showflat.php?Cat=&Number=464573&page=&view=&sb=5&o=&fpart=1&vc=1

Here is a link to a pricture of it:

http://www.rightspin.com/motorcycles/lowcostmano/mano.html

This thread also talks about a home made dial type guage.

I've not ever synch'd carbs this way but it would seem that you could sync carbs 1 & 2, then carbs 1 & 3, then carbs 1 & 4.

I think the cost of the home made guage is $7 for plastic tubing.


Frank

[stiksave]

Thank you. Just did'nt know if cm was a secret vaccum term. So a 25 cm reading will equall approximately 10 inches. That was my concern with this type gauge as it ranges from a 20" model or 40" model. Needed to understand the perameters in order to see if this gauge would work in the carbs range.

Thanks,
Stiksave

[earlfor]

You got it. No secrets around here anyway. :-) :-)

arl

Thank you. Just did'nt know if cm was a secret vaccum term. So a 25 cm reading will equall approximately 10 inches. That was my concern with this type gauge as it ranges from a 20" model or 40" model. Needed to understand the perameters in order to see if this gauge would work in the carbs range.

Thanks,
Stiksave

[stiksave]

Once I have it together I'll share. It's a commercial grade gauge. I should have 4 of the darlins tommorrow. Just a matter of setting them to read vaccum and mounting them onto a stand.

"Cheap is Good, Free is Better"

Stiksave

[earlfor]

Good going! Where there's a will, there's always a way. :-)

Earl

Once I have it together I'll share. It's a commercial grade gauge. I should have 4 of the darlins tommorrow. Just a matter of setting them to read vaccum and mounting them onto a stand.

"Cheap is Good, Free is Better"

Stiksave

[stiksave]

I got the gauges home today. Already converted to vaccum. I don't know how to add a pic here. So I'll add the url to view them. http://photobucket.com/albums/v643/s...t=HPIM0419.jpg

Thanks,
Stiksave