$12 carb sync tool

[Hooplehead]

Alrighty. This is going to be a sloppy page, but my picture editor went bad, so there will be rough cuts only. I have used this carb tool, and it seems to be very accurate. I got my adjustments down to the point that visually seeing the adjustment was too much. I actually ended up down to the finite movements that could barely be felt with the screwdriver. After and hour or so, the bike idles smooth and sounds awesome. Even as hard as I tried, the homemade gauge showed slight vacuum variances. So, I will assume that this gauge is as accurate as you could possibly need. Hell, you can only turn a screw so little .

You will need:

(2) 1/4 O.D. plastic line connectors. I found them at lowes in the plumbing section. $3-4 each.

(25') 1/4" O.D. vinyl plastic tubing. This stuff holds up to heat and vacuum fairly well. kind of an opaque plastic tube. $.07 a foot! $3

Some kind of board or plank. Anything to hang the hoses off of.

A plastic tee, but you could always rob the one that's under the gas tank. You'll need one of these to tee into the vacuum going to the fuel safety valve.

Zip-ties as usual.

1qt of 10/30 or 10/40 oil. And a cup or two of tranny fluid. I used 10/30 GTX and merc dex. Try and stick with the heavier oils, I used 5wt fork oil on my first attempt, and it was way too sensitive. The vacuum kept pulling the oil up too fast.

(3) 5mm bolts. Buy four! Get the longer one's and drill the smallest hole you can thru the center. I drilled from the botton and then used the grinder to lop the bolt heads off.

To assemble.

1)Hit the bong and relax.

2)Refer to step 1 then skip to step three.

3)

4)oh yeah, the gauge.

5)Cut the tubing into 4 equal lengths. 6' each should do.

6)Cut a 1" piece of tubing from scrap.

7)Connect the tubes as shown in picture.

8)Keep tubes straight and mount to whatever plank you are using.

9)Marvel at how simple this is and wonder how to improve the design.

10)Refer to step one then skip to step 11.

11)Take the 3 bolts, drill a very small hole thru the center (from the bottom).

12)Lop the head off the bolt but be careful to not damage threads at other end. I used Vise grips and a grinder.

13)Wrap with teflon tape a few times, so it will seal where it screws into the engine.

14)Screw the bolts halfway into the engine w/pliers.

15)Cylinder 2 should have a nipple that directs vacuum to the fuel safety valve. Using scrap, tee into it but cap off spare end.

16)Mix transmission fluid into the oil(not in the bike!) until it is the color you want. Don't go too thin however.

To Fill:

Get the gauge all set up, then unhook two hoses at the very bottom. While holding it upright, I took the oil (colored with tranny fluid) bottle and put the two unhooked hoses down in it. I then sucked the fluid up into the tubes until it was about 2 foot from the top on both. Wasn't too easy, but some of you could suck the bottle dry w/o issue I'm sure. Be sure to not draw air while you do this, or it takes a long while to settle! Put your thumbs over the tops, so you lose no oil, and re-connect the bottom lines. If you got it right, the oil will settle level in all four tubes. If you got some air, try swinging it or pulling vacuum on the line(s). You could always burn a lefty, stare at the thing for 20minutes, and be content that this just may work!

To Hook-up:

Locate all the vacuum ports. If you are blind, here you go. it's the 3 allen bolts and the nipple with a hose attached. Here is cylinder 1 and two (left to right). The other two are below carbs 3 and 4, inline with 1 and 2. If this confuses you, refer to step 1 then skip back here in 10 minutes.

I installed my 5mm bolts w/the telfon end in halfway. Leave the nipple and hose on cylinder 2. Using pliers worked fine. I also installed a tee into the fuel shut-off vacuum line coming from cylinder 2. I used leftovers, rather than cutting the factory hose.

Cap-off all the ends, Warm the bike and set idle speed (1100 +-100 rpm).

Shut-off the bike, uncap the ends, and hook all the hoses up. Cylinder 2 will hook up at the tee for the fuel cut. Be sure to hook the hoses up in order, so you can easily tell which cylinder goes to which tube on the gauge.

Start the bike and be ready with the kill-switch. Using oil probably won't damage the engine, should some get sucked up. However, if any of the levels get down to the tee fittings at the bottom of the tool, it'll draw air and you'll have to try swinging it or pulling vacuum on the line(s). You could always burn a lefty, stare at the thing for 20minutes, and be content that this just may work!

It took me starting and shutting off the bike maybe half a dozen time before I got the balance adjusted to where the gauge would be steady enough, long enough, to adjust it on the run. Remember, cylinder 3 does not adjust. The oil never got too far, it just sucked a little low at the beginning when my carbs were out badly! I can't remember which way to adjust to make the vacuum more. I believe that loosening the screw would decrease it, yet I may be wrong. Let's just say I had to "recalibrate" enough that I barely recall.

The gauge worked perfectly! The bike idles smoother and seems to have better throttle response. I haven't had a chance to ride it, but it sure sounds better! i have a quick-time clip of the gauge working after I was finished. You can rev the bike and watch the vacuums go rock steady. Seems like the vacuum pulses completely disappear when you gas it. Really cool to watch. The video sucks, and I don't know how to post it. It's 6mb so if anyone wants it, tell me how.

If you have any questions, read the fucking manual and refer to step 1 of this how-to.

Peace you bunch of Wangs!

-Shane aka hooplehead

here's a 3$ prototype version that didn't work!

Edited July 7, 2008 by shanesublett

[blackhawkxx]

Good job and to think that some people call you a hooplehead.

Just thinking out loud, why couldn't you just stick the end of the four hoses into your quart of oil at the bottom of the board instead of connecting them together?

[Hooplehead]

Good job and to think that some people call you a hooplehead.

Just thinking out loud, why couldn't you just stick the end of the four hoses into your quart of oil at the bottom of the board instead of connecting them together?

Doing that would only succeed in getting oil into the engine. This isn't a vacuum gauge so much as a balance gauge. If you were to just put the tubes in oil, you would be balancing against atmospheric pressure, thus oil into engine. This tool is measuring vacuum between each other. When you get a small increase in vacuum on one cylinder over another, the low cylinder starts to lose it's tug of war with the other(s). I sat and pondered on this for a minute, and it makes perfect sense. Reefer to step one! It is really amazing how the pressures affect one another in this system. After about 5 minutes of use, any normal hooplehead could understand the relation between the four cylinders. They all act cohesively on the gauge, but it's still a bitch because of how the adjustments on the bike all react to each other. At least cylinder 3 gives a no fuck-up reference point!

Now you the hooplehead too!