How to make a bottle style manometer.


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Ok, I made one of these manometers instead of the usual ones a lot of the others have posted because there is no risk of sucking fluid into the carbs with the bottle style.

What you need:
-2 glass snapple bottles
-10-11 feet of clear tubing about 1/4 inch od and 3/8 or so ID.
- two rubber stoppers to plug the holes on the snapple bottles.
-and some automatic tranny fluid, or whatever fluid you want to use.

so in end you will prolly end up spending less than $10 for the manometer, 2 bucks for the bottles, 3-4 dollars for the tubing,and a dollar or two for the stoppers. Most people have some type of fluid sitting around the garage.

1. drill two 1/4 inch size holes in each rubber stopper just big enough so you can jam the tubing through, yet still small enough so it is air tight.

2. Cut a piece of tubing about a foot so it can go from the bottom of one bottle and the other end goes into the other bottle all the way to the bottom.

3. Measure and cut the rest of the tubing so both sides are equal and place one of the now 2 tubes into one of the rubber stoppers just so you can see the tubing through the rubber, but no further into the bottle, do the same with the other tube to the other bottle.

4. Fill each bottle with a couple inches of fluid and put the rubber stoppers back in the bottles and make sure you get the stoppers in far enough so they don't pop back out.

5. After the bike is warmed up, shut it off and hook up the two long tubes one to each vacuum port on the intake boots, then start up the bike.

6. The fluid IF SYNCED CORRECTLY will stay even in each bottle, but if the carbs are out of sync one bottle will start sucking the fluid from the other. If this is the case then you need to adjust the screw that adjusts when the butterfly valves open while the manometer is hooked up. As you adjust you will see the bottles evening out and once they are even stop adjusting and watch for a minute or two to make sure the fluid has stopped moving and stays equal and then your carbs are SYNCED off of the BOTTLE!!!!

See picture if you get confused, it's pretty easy to figure out. Let me know if you want more pics of the manometer.


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well ya you can even see one of my shoes in the background:thumbsup:

here's another picture from above so you can better see the stoppers and how the tubes are in the bottles.


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Looks easy enough but where would someone get those rubber stoppers from? I haven't seen those since chemistry class
I bought my rubber stoppers at ace hardware in the aisle with all the bolts and nuts, they were only a dollar a piece i think. They also had a number of different sizes in case you use a different class jar or bottle.
drewpy, I don't see why not. they already have holes in em right?

rubber stoppers: ace has them, lowes has them, home depot has them, you name it.

I used the little bottles from Preval spray kits. check your rig before use with a vacuum brake bleed tool or other single vac source hooked to BOTH inputs at once (the brake tool I got came with some T's)
if the liquid moves when both are hooked to the same source, plug the leak in your rig before getting near your bike with it.
(it's worth spot checking your dials this way once in a while drewpy, springs can vary, don't trust em w/o some sciency type logic in your corner)

I'm big on inspecting gaging equipment. I've seen too many guys put a two thou ding in their calipers and make parts that are EXACTLY two thou undersize for weeks thereafter without even realizing it.

it's worth mentioning that before attempting to vac sync carbs you will get NOwhere without FIRST.

making sure valves are in spec
making sure carbs are money clean and CV's drop shut with a snap
no vacuum leaks
bowl floats set
Bench sync

it is also advised when adjusting that although synch adjusters are spring loaded still take that lash out of the equation. that is if you want to back it out a half turn what you should do is back it out one full turn then in half a turn (just an example, that's actually a lot of adjustment). for this reason I like to bench sync then back out a 1/4 turn and sneak up on it. Same goes for idle mix screw. the correct way to get to say 2 1/2 turns out is to back out 3 from seated then in 1/2
I am probably going to try this myself; I like the idea of not being able to suck any fluid into the engine because my carbs are probably way off.

Is there a recommended fluid for this? Would a low viscosity be desirable since the risk of sucking it up is eliminated?
Sounds like a lot more stuff than you need. Just 15 to 20 feet of hose, a stick some tape and any bright or dark fluid. On ounce or two at most. If your engine does suck it in, it will just blow through and out the exhaust.
I tried the traditional home-made manometer before, but it defeated me and proved to be messy; I gave up on it.

Today I bought the supplies for a bottle-style one. I will follow up with my results.
To be clear ..the levels of fluid in the bottles don't need to be the same they just need to be at a point where they stay steady for a period of time between idle and a high rpm ...this is what I've learned from others. Correct or not? I don't personally know bc I haven't got to that point yet but can't wait to try this!
sub'd. thanks for sharing this bcboobers. One question, on the second pic, I see a Wilderness Kayak manual. Which model do you have and how do you like it?