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Was assembling my Motion Pro Synchronizer #08-0009. I was installing the restrictor plugs per the instructions. When I noticed that one of them had a piece of plastic flashing near the orifice. The thought occrued to me. That if I had pushed it in the tube like that it may have been forced back into the opening. Causing more restriction. It was the last one I installed of course. :( So I tried sucking air thrugh the four tubes. To see if I could desiren any difference in flow. SURE enough. 2 of them were about the same. I put them on tube #1&2. #3 got the one that seemed slightly more restricted. The one that seemed most restricted went on #4.
:? My Question is will this affect the vacume readings?
I have noticed in the past several threads where people were haveing trouble getting accurate readings. Could this be the cause?
This will be my first Sync attempt. I install the tubes in the order above so I could attempt to answer this Question myself. However I will not be able to get to the job for a few days. So I figured maybe one of you very wise souls out there could inlighten me about vacume Versus volume.
 

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No.

In my experience, the amount of restriction will only affect the dampening of the bouncing, but not the reading.

When you run the bike attached to the sync tool, you can see for yourself by gently pinching individual tubes.

Vacuum IS different from volume.

I use one of those.



:)
 

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To my knowledge, no. They will all bounce. The reading is the 'perceived' average of the bounces. The amount of restriction will only 'shrink' the range of the bounces.


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LOL

I'm not an engineer, but I play one on TV. ;)

Those were my impressions after kinking and piching the lines of the sync tool, because I too was curious about that.

I've been using that tool for several bikes now. Simple, but it works well.



:)
 

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Liquid is right. I use a TwinMax electronic guage for TB syncing and it doesn't use restrictors, but to check the amount of vacuum at the cylinder I want to sync to I use a common vacuum guage I bought at the auto parts store. Big dial and big hose and the needle jumps around so bad you can't tell what the reading is. So I just pinch the hose a bit until the needle settles down and all is well. It's definitely not brain surgery.

Note, however, that it is still nice to have all four tubes of mercury on your carb stick bobbing up and down at approximately the same rate and tolerance so you are comparing apples to apples. The restrictors don't have to be exactly alike but should be pretty close or you could have one tube bobbing up and down about 2 inches and another only 1/4 inch. Identical restrictors just make it easier to make similar adjustments.
 

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Restrictors

The restrictor orifices do affect the column heights. When I first started using my Motion Pro economy model I checked to see if the columns were the same if they were connected to a common vacuum source. They weren't. There wasn't a huge difference but the error was greater than the accuracy I wanted.

I had a few needles from various sewing kits I'd collected at hotels over the years. I selected one needle that was snug in the largest orifice. I then pushed this needle through the other orifices until they were all about the same. Now, with a common vacuum source, the four readings were much, much closer.

The position of the orifices affect the bouncing of the columns. The closer the orifice is to the mercury the bigger the column bounce. Thus for minimum bounce you'd move the orifices to the end of the hose nearest the engine.
 

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Very contrary to what I've experienced with the unit. I also swapped the lines around and got the same readings. The bouncing is not that dramatic at all. I've synched about 20 different bikes with it.



:)
 

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Gents, I haven't used the synch device that you are talking about, but for what it's worth, with the Morgan Carbtune II you put a piece of plastic with a needle sized hole as a restrictor in the 4 tubes. You place the restrictors CLOSER to the engine than the Carbtune to dampen the readings & provide greater accuracy. Hope this helps.
 
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