Carburetor Syncronisers.

[KiteSquid]

Seeing your drawing reminded me of the mercury oral thermometers from my youth, sometimes they needed to be "shaken down" if there was a break in the column of mercury, and they are a sealed instrument...

 

Sounds like you experienced the same issue, but I would not recommend "shaking down" the mercury in a manometer as they are NOT a sealed instrument.

 

Good job on correcting your issue.

[Brake Pad]

I did'nt read all the posts, so I'll start here.

I had mine tested yesterday

1. 18

2. 24

3. 31

4. off the chart

what are they supposed to be?

also, I see sometype of grease, all over the carbs? any ideas?

[Dave77459]

Based on this article and my needs, I have settled on the Motion Pro SyncPRO Carb Tuner. It comes with 5mm adapters, but the product website seems to say I need the 6mm adapters (extra cost).

 

Should I buy the 6mm adapters, or am I set with what comes in the kit?

 

Dave

[Squeeze]

You don't need any Adapters. The Ports are already in the Carb-Boots, plugged with Rubber Caps.

[Dave77459]

You don't need any Adapters. The Ports are already in the Carb-Boots, plugged with Rubber Caps.

 

Awesome. Thanks!

 

Dave

[GaryZ]

Greetings...

 

Let's talk accuracy for a second...

 

But if you are riding a 20+ year old machine (like a lot of us are) for fun or economics, and aren't overly anal retentive - Any difference in accuracy between syncing your carbs with a simple $3.50 oil column or a $100+ mercury filled High Tech gizmo - is going to dissapear the instant you come home from this weeks ride - That's reality - When you ride - your carbs go OUT of sync. It's called entropy. It's a law of the universe.

 

 

You make an excellent point here. However, most folks are too wrapped up in their own ego to accept such a simple idea. BTW, have you been watching me synch the carbs on my VR? You described my adjustment method almost exactly!

[Sideoftheroad]

I did'nt read all the posts, so I'll start here.

I had mine tested yesterday

1. 18

2. 24

3. 31

4. off the chart

what are they supposed to be?

also, I see sometype of grease, all over the carbs? any ideas?

 

Others more experienced can chime in here. I haven't synched mine or have watched it done, but from reading several posts here about the subject, there isn't any set level (like all of them have to be 24). You just have to make sure that they are all equal across the board regardless of what the number is.

[MiCarl]

$9.00 for 32' of tubing and $0.50 for 50ml gear oil. Worked perfectly!

 

(Well, there was the $35 tachometer and the $5 10" #2 screwdriver.)

 

http://hosting11.imagecross.com/image-hosting-01/2397Homemade-Manometer-3-.jpg

 

I like this design. I don't see how adding bottles does anything more than make extra work and places for it to leak. Placing a couple "T"s in the bottom of the loop will let you have 4 tubes so you can sync the whole thing at one shot. Probably add $2 to the price tho.....

 

BTW that set up is not accurate, it is however sensitive (more sensitive than mercury sticks which are accurate). What I mean by that is it in no way will tell you the pressure in the intakes, just the relationship. The MotionPro SynchPro is similar. That is perfectly fine for synchronizing and I love my SynchPro.

 

If you have even one cylinder that is not firing the vacuum on a synchronized motorcycle will drop very low. There is no way to see this situation on an open manometer (above) or the SynchPro. With mercury sticks or gauges you can see that situation at a glance.

 

I still slap the vacuum gauge set on if I have any suspicions about how well the engine is running.

[Guest scarylarry]

I went today my dealer for a retro fit on the CD holder and while I was there I ask the dealer on sync. the carbs. since I do most of all my own except the valves, and he told me 150.00 to to do the carbs. and it was like a 1.5 hr job and the tank had to be remove...I thought I was going to fall off the stool...

 

Thanks for all the info here...

[KiteSquid]

I did not have to remove the tank to synchronize my carbs.....

[Guest scarylarry]

That kinda got me, but 150.00 for carbs....thought that was pricey

[KiteSquid]

My dealer did them for free at my 600 mile maintenance, but now I have a set of Mercury Manometers, so I adjust the linkages myself.

[SilvrT]

I went today my dealer for a retro fit on the CD holder and while I was there I ask the dealer on sync. the carbs. since I do most of all my own except the valves, and he told me 150.00 to to do the carbs. and it was like a 1.5 hr job and the tank had to be remove...I thought I was going to fall off the stool...

 

Thanks for all the info here...

 

It cost me $75 and it took the mechanic less than 10 minutes!! No removal of the tank.

[david e]

i was told it is a common thing with ventures? any one with expeirience with this problem

I think it might be dirty carbs and air filter.

[V7Goose]

i was told it is a common thing with ventures? any one with expeirience with this problem

I think it might be dirty carbs and air filter.

Yes, this is a very common issue on these bikes, and it has been discussed here MANY times - a search for afterfire, backfire, popping, or decel will find more posts than you probably want to read.

 

In short, this is caused by incomplete combustion of the fuel and/or exhaust leaks. The two most common issues are vacuum leaks at the rubber caps on the intake manifold nipples and poor carb sync. Many of my older posts will go into causes and fixes in much more detail. You will also see many members suggest you just disconnect the AIS to simply hide the symptom of your actual problem instead of fixing your bike. I think this is a really dumb thing to do, but everybody will make their own decisions.

 

Here is one thread with a lot of technical information on how the AIS works, especially if you look at my post #24:

http://www.venturerider.org/forum/showthread.php?t=22961&highlight=afterfire+popping

 

And here is another post where I spent a lot of time trying to describe the unintended VALUE the AIS gives you:

http://www.venturerider.org/forum/showthread.php?t=38403&highlight=plugs

 

The bottom line is that a stock RSV in good tune will NOT pop on decel unless something is wrong with either the combustion or the exhaust system.

Goose

[saddlebum]

this is one I made myself and if your good at scrounging should cost next to nothing. It only use's one guage to avoid discrepency. you simply open the valve linked to the cylinder your working on and take a reading. dampening is accomplished by adjusting the needle valve.

 

[ame=http://venturerider.org/forum/showthread.php?t=36518]home made carb tune tool - VentureRider.Org[/ame]

[massey130]

http://www.sportingforless.com/servlet/the-carb-sync-gauge/Categories

this is where i bought my carb sync tool from. paid 48.5o shipping included. i have not used it yet but hope to real soon. just plain busy and when i get some "free" time, i will either sit at the PC and surf VR or i will stand at my lathe and make some wood shavings. i have some scooter stuff planned when it gets a bit colder . i am still waiting on my rear tire, also. anyone loose an unused pop rivet? no takers from my previous thread.

it is a tuner that was pictured before. but i have doctored the original to be more user friendly. I believe i have some vacuum leakage at the the vacuum rubber cover, but i will take care of that then as well.

[Mandride]

I have used the Emgo to synch my 96 Royal Star and and my 82 Honda Goldwing. It works great and you can get it from JC Whitney

[atlm]

I've been looking at the different carb sync tools because I'd like to buy one, and have questions I'm hoping someone here has the answers for.

 

The Motion Pro SyncPro needs to be calibrated, and shows a procedure in the instructions. Why is that? If it's simply 4 tubes with liquid from a single source, how could that go out of calibration? I've seen the thread in these forums that clearly shows the tubes out of whack at different RPM, but don't understand how that happens, unless the ID (interior diameter) of each tube is different, which I wouldn't expect with today's manufacturing tolerances.

 

There's the mercury unit on eBay sold by Saber, which doesn't mention a calibration procedure. Is this unit perfectly balanced in some way different than the SyncPro? Or does it need calibration, and is it just built cheaply, without the option? Is there something different about mercury than the blue fluid that makes it stay in calibration? Or is it all about manufacturing tolerances, and the ID of the tubes? Does anyone who owns this unit ever hooked it up with a common vacuum divider to test its accuracy?

 

Then there's the Morgan carbtune. Does that unit ever need calibration, or is it always right on the money if kept clean and rarely used? I know with its moving parts that if it was used every day it would wear and go out of whack, but for personal use, a couple of times a year maybe, wear shouldn't be a factor. But, it seems the the plastic aging and possible distorting over time could be a factor. Again, has anyone who owns this unit ever hooked it up with a common vacuum divider to test its accuracy?

 

I'm sure in the end they'll all do the job fine, but I'd like to get the one that's most accurate and the lowest maintenance, if possible. I like these 3 because they're small and can easily fit in a cabinet out of the way when not in use. I also like the 4-side-by-side tube design, since it looks easier to read when synchronizing the carbs than the 4 needle gauge setup. The mercury unit is $44, the SyncPro is $86 and the Morgan is $94 (prices include shipping).

 

It appears on the surface that the mercury unit is the most accurate AND the lowest cost (home built specials not included). Am I missing something? My only hesitation is the mercury. It the unit well sealed? No children in my garage, but at the same time as being very useful, it seems like mercury is pretty nasty stuff. Although I don't know how nasty, since it was used in thermometers for like 100 years.

 

[V7Goose]

In my experience, the Motion Pro unit is simply junk. I cannot explain why they do not maintain the same calibration at different amounts of vacuum, but that is just one of the reasons I unhesitatingly label them as junk. I base that opinion on hands-on testing.

 

Mercury is the long-time standard for measuring vacuum- it is a very heavy metal (also very dangerous) that would require no calibration beyond ensuring the level of each tube at rest is the same. It is possible to break, spill, or accidentally suck the mercury into an engine.

 

The Morgan CANNOT be calibrated, as is stated plainly in the instructions that come with it. This is unfortunate because it DOES need this capability. I unpacked and checked a brand new unit for a friend and found one of the tubes significantly off from the others. I managed to fix it by bending the spring, but that should not have been necessary. This tool works on a different principle from the other gauges; it does not actually measure a true vacuum level, but relies on measuring the volume of air rushing by the steel rods and suspending them. Personally, I absolutely detest the Morgan carbtune in use - it sticks a lot (even when brand new or properly cleaned), must be held scrupulously vertical, and requires constant tapping to ensure the reading is correct before you accept what you see.

 

You seem to have just dismissed the possibility of purchasing the mechanical four-gauge set. I have had mine for over 30 years, they are very rugged, and they can be easily calibrated (but virtually never need it). They used to be about $50 at JC Whitney, but their price went through the roof in the past year or so. However, with a little bit of searching on the web, you can still find them for around that price. In my personal opinion, this is the ONLY sync tool worth buying.

Goose

Edited January 21, 2010 by V7Goose

[Larry M]

Wow, after reading the posts on this article I'm wondering if anyone else feels the same? First, I bought a Morgan Carbtune late last fall because of the feed back on them and others, I haven't used it yet and almost afraid to because of the feedback! It seems there are so many biased opinions on tires, windshields, carbtunes, oil and many other items that a person don't know what the hell to go with! I realize feedback is good but can get confusing at times!? That's just MOPO...

 

Larry M

[V7Goose]

Sorry if my thoughts caused confusion, consternation or discombobulation. In my defense, however, I must state that I have posted my thoughts on those tools several times in the past.

 

Certainly the Morgan Carbtune is very popular with many members here. I do not wish to speak for any of them, but I do wonder if the people who actually say they like it have ever used a better tool? There is also the possibility that someone who has already bought an item and finds it at least usable will at try to tell themselves that they like it instead of publicly kicking themselves for maybe buying the inferior item. The Morgan Carbtune DOES work, but it is easy to get a wrong reading, and it is just not worth the effort to use it for me. The problems with this tool are instantly noticeable every time it is used, and I have personally pointed them out to many who have watched me use it.

 

The mechanical gauges work absolutely consistently and with no variation every time. True, the needles have to be individually looked at instead of just seeing if four rods are level, but that is not a negative to me at all. In just a glance I can as quickly see if all four gauges are about the same, then a closer look at the actual vacuum reading on each gauge confirms if they are absolutely identical.

 

I am only speculating on those things, simply because I have personally used all of the different tools mentioned here, and I honestly cannot understand someone finding the Morgan Carbtune acceptable after doing the same comparison. But that is just my opinion, so if someone else DOES find it acceptable, or even the best option, well, their opinion is every bit as valid as mine. At least I tried to give y'all very specific details of why I hold those opinions so you can make up your own mind instead of just accepting my advice. In the end, I believe you will get the best and most consistent results from a tool that you fully understand and personally like. Good luck on liking whatever you choose!

Goose

Edited January 21, 2010 by V7Goose
pontificate some more

[atlm]

Thanks for all the information and your opinions, Goose! There's something I'm not clear on, though. If mercury is the long time standard, why do you prefer the mechanical gauges over the less expensive mercury setup?

[V7Goose]

Because mercury stix are more bulky, harder to store, easily broken, can loose their mercury from breaking, spilling, or getting sucked into engine, and the stuff is dangerous. As far as I am concerned, they provide absolutely NO benefit over mechanical gauges and a lot of draw backs.

Goose

[atlm]

Don't hold back. Share what you really think.

 

 

I've been concerned about a mercury mishap since looking into different gauges. I've just had a bad feeling about it, and have learned to listen to those feelings over the years. So, I've been hoping to find a good alternative.

 

Since you have had such good luck with the dial gauges for so long, and haven't found them difficult to use, I'm leaning towards going with a set of those. I had only previously crossed them off the list because I thought they would be much harder to read, but that doesn't seem to be the case. Saber Cycle has some via eBay for about $52 shipped.

 

OK, three more questions:

Are yours the Emgo gauges, like those being sold by Saber?

Did you do a similar test with yours as you did with the Motion Pro unit, testing their calibration across different amounts of vacuum with a hand pump? Is that part of what you refer to when you say the mechanical gauges work absolutely consistently?

Is my understanding correct that they can be calibrated?

 

Let me know. If so, I think I'm sold.