TB sync-manometer

[kmac]

Afternoon guys,

I just made myself a homemade manometer. I used a piece of 1/2" thick x 5" wide x 4' long piece of oak floor plank. I painted it bright white so i could see the movement of the fluid easily.

I got 20' of 1/4" clear tubing at home depot for 3 bucks. And being a MX, desert, dual sporter i have hundreds of zip ties in the garage. I filled the tubing with water that I had put some yellow and red food dye in...orange IS my favorite color...I used the vacum/straw technique to put about 4' of fluid in the tube. Once I got the fluid settled I zip tied the tubing to the plank of wood with the center of the tubing length (priviously marked) at the very bottom of the board and zip ties about every 8" or so up to the top of the board. After the orange water settled I marked a straight line across the plank between the 2 tubes. The contrast of the white board, black level line and orange fluid really pops nice.

 

So now monday I am gonna do a sync. Any ideas on anything my system may need?

 

My service manual doesn't have much on tuning. Once the tubes are connected to the TB's and the motor is running, if one side is showing more vacum, pulling the water on that side higher in the tubing, which side do I adjust? The side that is pulling more or less vacum? Any links to TB sync and adjusting tips?

 

I have used the search function here, and either I am terrible at it, I don't understand it, or I just haven't found it after PAGES of reading. I just would like a "how to sync" link....

 

 

Thanks Guys, you are awesome...in advance...

Kelly

[NonComp]

Always adjust the right-hand side cable for off-idle sync. Leave the left-hand side as a reference.

 

Turn the Big Brass Screws all the way in and then back them out a about 1.5 turns to start. BBS set the idle sync.

 

By the way, I used two-stroke oil instead of colored water. The viscosity damps the response a bit.

[Fraidycat]

Kmac----I've had some experience here with a similar setup---and recommend that you insert some small 'sleeves'--- orifices) in your tubing to start with. The reason for this is that if your 'balance' isn't just really close the water on the side with the most vacuum will suck up so fast that it will suck ut up and over your 'loop' and right into your throttle body before you can shut your engine down. For that reason you want a very small orifice inline on each of your tubing leads----Put them maybe a foot from the end of each tube and inline with the tube (not far from where they hook to the throttle body's). Try inserting a 1/& 1/2 inch long length of coaxial cable with the center wire pulled out into your tube and see if that will fit tightly . This will provide you with a very small orifice which will limit the amount of water you will 'suck' with each stroke----. Do your initial tuning with this way and progress to larger I.D. orifices when you have the vacuum pretty well balanced. The larger orifices will, of course, give you a much 'finer' adjustment but if you get them too large you will have a devil of a time getting them to balance because it takes a period of time for the 'sucked' water to drop back---i.e. if the 'stroke has switched to the other cylinder before the water in the tubes 'neutralize' then you are never going to measure and display a true 'balance' of vacuum. In my experience an orifice' of about 3/4 to 1.5 inch long with an I.D. about the size of a coaxial solid wire works best.

[Fraidycat]

OR---of course, you could just use a heavier medium---as suggested by non comp. I prefer colored water myself with the orifices because water reacts quicker than oil and (I think) gives you a finer reading----if you get the size of the orifices right.

[kmac]

This is why I asked the question...all great ideas. I like the idea of 2t oil, wont hurt a dang thing if it does suck into the motor, neither will water really in the small quantities that the tube has in it.

 

Orifice was a thought I had never heard of, nice heads up.

 

What about a clamp? Start the bike with a clamp on the tubing, then pop off the vice grip clamp? I guess if one side is way off from the other it would still pull the medium thru tho right?

 

2t it is i think...do i still need an orifice if i use 2t oil?

I have a jug of Maxima Super M {which coincidentally is Orange} in the shop i can use.

 

So for an orifice what are you using? A piece of plastic with a tiny hole drilled into it? Then shove it down into the tubing?

[nrp]

You can be sure any fixed orifice isn't going to be what you want. I'd use a single vise grip or small clamp on the tubing between the two vertical columns.

[dan cata]

I have found out that transmission and FD oil works best for me.

 

When you adjust the cables in the rev section, it's best to keep the bike rev'd ad 2500 RPM using your right hand, and with the left hand adjust the R/H side cable, so you will want to adjust it as it is rev'd, instead of reving the bike, adjusting, rev again, adjust, etc

 

A, and for idle sync, make sure that both plates are resting on theire stopping screws

 

Dan.

[Boffin]

Afternoon guys,

I just would like a "how to sync" link....

 

 

 

The Oilhead Maintenance Manual will suit your needs.

 

 

Andy

 

 

[boatzo]

In reference to the BBS, I like to remove them and clean them. Also clean the inside where they go. Then seat them and back em out as described.

[NonComp]

I chose tubing with an inside diameter that matches the nipple size. Keeps things simple. I don't use an orifice and don't find I need one. I used a clamp-off that was left over from wine making the first time I tried this, but then decided that it wasn't really necessary either. You can easily grab and double the hose over if things are way out of balance.

[Starfighter]

I use ATF in my manometer.

Always a great sync. and my baby purrs.....

[kmac]

Ok so 3 more questions for you guys.

 

If I use a heavier medium like atf, 2t lube, diff fluid...I do NOT need the orifice in the ends?

 

When i am setting the high speed sync, can I use my throttle lock to hold the rpms steady at 3500 rpm while I adjust the crossover cable?

 

Is it a good idea to put a small clamp on the tubing until after the bike is running so that the vacum is consistent, then remove the clamp?

 

Thanks guys, the links and input have been awesome and much appreciated.

[dan cata]

Ok so 3 more questions for you guys.

 

If I use a heavier medium like atf, 2t lube, diff fluid...I do NOT need the orifice in the ends?

 

When i am setting the high speed sync, can I use my throttle lock to hold the rpms steady at 3500 rpm while I adjust the crossover cable?

 

Is it a good idea to put a small clamp on the tubing until after the bike is running so that the vacum is consistent, then remove the clamp?

 

Thanks guys, the links and input have been awesome and much appreciated.

 

1 I say use motor oil, 20w50. The thicker oil adheres more to the hose walls, if one side is way off, you won't get consistent readings because of the oil remaining on the walls.

2 The throttle lock would work, but set it at 2500 rpm. At 3000 or higher rpm, the plates are opened too much and the sensitivity/accuracy of the device decreases.

3 No need, during first adjustments, rev the engine for 1 sec, see which side needs adjustment most, adjust, repeat, until you can keep it at a constant 2500 rpm. What you want to do would deform the hose.

 

 

That's how I do it and works just great