Need Help synchronizing my Carburetors

[Vonwolf]

I finally got my '87 running and am trying to sync up the carb's, but I'm having problems. I'm using an old 4 vacuum gauge setup and the no 1 carb is steady, but the other 3 are bouncing all over. I think I've ran into this problem before, but I'm not sure, I think there needs to be some kind of valve in each line to act as a dampener, but I'm not really sure and the number 1 carb holding steady really throws me off? I suspect the valves need adjusting but again I really am not sure, I've owned the bike for 6 years yet I have probably only put 25 miles on it. if anyone can tell me what I'm missing again I'd be grateful

[Flyinfool]

Just for testing switch hoses between 1 and any other carb. Does the same gauge stay steady or does the steady move to a different gauge?

[Squidley]

In the units like the carbtune, which is what I have, there are restriction tubes in them to help keep the slides from bouncing. I would be willing to bet that your issue is arising from not having them in your vacuum lines....0.02

[Vonwolf]

In the units like the carbtune, which is what I have, there are restriction tubes in them to help keep the slides from bouncing. I would be willing to bet that your issue is arising from not having them in your vacuum lines....0.02

 

I think you're right I need some kind of valve to restrict the vacuum and calm the gauge down. The one that does work kind of throws a wrench in this theory so I do have to switch them around and see if the gauge is bad or everything else is bad, the fun never ends

[Patmac6075]

You can make a simple restricter.... all you need is a vacuum hose coupling (those barbed couplings available in any auto parts store, sized to your vacuum hose of course) and a straw from an old can of WD-40 (or brake cleaner), and some epoxy. Insert the straw onto the coupling (making sure you have plenty of straw sticking out on both ends), now fill the inside of the coupling with the epoxy, let dry, then trim the straw to the same size as the coupling (the coupling should be blocked and the much thinner straw should be clear).

Now I'm not sure about this part, but the restricter/coupling should be very close to the vacuum source which allows the vacuum pulse to even out....or it's the other way around....I can't remember, but it works!

[zagger]

It has been quite a long time, but as I remember, I made simple restrictors by inserting the threaded portion of a bolt into the tubing so that the only airflow has to pass down the tiny passage created by the thread. The restriction can be adjusted by changing the length of the threaded bolt. Without a restriction, the pressure measuring guage will jump all over the place. You can experiment with the restriction for the best gauge reading.

 

Many years ago I tried a U shaped tube with liquid inside to measure the vacuum (I forget whether this was on my venture or another bike). You cannot imagine how quickly the engine slurped that liquid in one gulp! Fortunately, the tubing ID was pretty small and the engine didn't even notice! That's when I switched to liquid-free gauges.

[videoarizona]

They make vacuum restrictors...really cheap...most auto stores. Cut hose, insert restrictor into hose.done.

 

http://www.oreillyauto.com/site/c/search.oap?keyword=vacuum+restrictor

Edited April 14, 2015 by videoarizona
add

[Brenner]

I personally use the old school mercury filled manometers. My unit has 4 tubes so it is perfect for the venture application.

[Vonwolf]

Thanks for all the suggestions If I would have seen them I probably would have saved some Money. I ended out going to Homer and getting 1/4" Quick Release Valves, with these I can just restrict the vacuum till it stops bouncing all over, well at least that's the plan I hope to get a chance to try them out tomorrow.

 

The only flaw in my plan is the 1 gauge that doesn't bounce at all, I tested it on Carb #1 and #2 they both were steady so there's something strange going on with that gauge. I just hope it gets me close

Edited April 14, 2015 by Vonwolf

[friesman]

have a look at this in case you ever get mercury sucked into your engine accidentally.

 

I personally use the old school mercury filled manometers. My unit has 4 tubes so it is perfect for the venture application.

[Condor]

Exactly my thought when I saw that post Brian. Too much damage can be caused using 'old school' mercury syncs. Hopefully if they are used the carbs are fairly close to being sync'd, or it could be come very expensive, and I'd never use them on a fresh rebuild.....

[Brenner]

Well to each their own, and I have never known anybody to pour that much mercury into a stationary object and use a time lapse camera to see the effects. A running engine being set up by a competent mechanic that knows how to setup and use a tool correctly really has not to worry about this concern. How many bikes have been set up using these tools over the years? How many reports of damaged engines due to this procedure? I know how to use the tools that I own correctly without adverse effects, have done so for years in a licensed trade and am competent enough to be able to set my carbs close enough to not have a problem using my manometers and it is not my fault many others may not be skilled enough to do the same. I did not post my experiences a to be put down by others that feel they are superior or know better. I see many things on this forum that I do not believe are right but I am respectful enough to keep my opinion and negative comments to myself. Just because one person may not have the skill or talent to use a tool correctly does not mean that others have the same result. Now if I was instructing someone to do something dangerous to hurt themselves call me out on it but do not judge my competence due to your negative experiences or inadequacies. EVERYONE has an opinion and having an opinion does not make a person right. I really do not appreciate the judgement and take it as an insult. It is my mistake as I was under the impression this forum was supposed to be friendly and positive but I am now corrected. I will gladly back up my claims efficiently, effectively, and far faster than most. Flat rate competition as shop foreman for over 20 years has made me what I am.

[Freebird]

I hate to ruffle any feathers but feel that you need to lighten up a bit. Showing what can happen if the mercury gets sucked into the engine can be nothing but helpful. Nobody said that you didn't know what you were doing but that does not mean that the possibility of it happening shouldn't be mentioned in case somebody might not have your expertise. To be honest, I have seen it happen and it's not always because the person didn't know how to use the tool. There are certain conditions of the engine and settings of the carb that can cause it to happen almost immediately. I saw it happen to a good friend who has synced hundreds of these carbs. As far as I know, it didn't cause any problems but apparently it is possible that it could. You are correct that this forum is friendly and positive but it is also a source of many opinions that may not always be the same as yours.

 

Sorry, but I think it was your response that was less than friendly.

[Brenner]

I hate to ruffle any feathers but feel that you need to lighten up a bit. Showing what can happen if the mercury gets sucked into the engine can be nothing but helpful. Nobody said that you didn't know what you were doing but that does not mean that the possibility of it happening shouldn't be mentioned in case somebody might not have your expertise. To be honest, I have seen it happen and it's not always because the person didn't know how to use the tool. There are certain conditions of the engine and settings of the carb that can cause it to happen almost immediately. I saw it happen to a good friend who has synced hundreds of these carbs. As far as I know, it didn't cause any problems but apparently it is possible that it could. You are correct that this forum is friendly and positive but it is also a source of many opinions that may not always be the same as yours.

 

Sorry, but I think it was your response that was less than friendly.

 

 

Freebird I respectfully understand your response. I my defense why would someone post a time lapsed video of a sizable amount of mercury poured on a stationary piece of aluminum stating that I would destroy an engine? Am I that stupid to pour mercury into an engine and wait for it to react? Is a running engine stationary? Or when mercury contacts the running engine does it damage on contact? My point is that all I stated was that I used my manometers on my venture successfully. I did not tell anyone to use them only or what was right and wrong and now I have others posting how I may be damaging an engine. All they needed to state was in their opinion they are not comfortable due to their specific reason. Traces of mercury that may have inadvertently made it into in a running engine will not in no way do the damage that they have shown. Believe it or not there is a combustion process in the cylinders in which the mercury would make its way into by means of vacuum then expelled through the exhaust. Time is a factor in this chemical reaction and I personally felt that video was unnecessary as it does not apply to a moving component as an engine. I have seen posts where I have seen comments made by those against me were in my opinion wrong but I was courteous enough to consider the fact that they had an opinion too so I did not reply. Why were they not friendly to me and serve me the same courtesy? When I am unsure or do not know something I openly admit it but I am not comfortable with others trying to make me look bad intentionally or not by use of a time lapsed video on a stationary object. I do not want problems and if you review all my posts and comments since I have joined I believe I have never put anyone down, degraded another or another's choices. I have highly praised this forum, advertised to others, and have a the site address sticker on the front of my bike and the emblem from you on the rear and highly respect those who have assisted and made constructive recommendations. Now I feel that the dog I have been petting has turned around and bit me for no reason. Touchy? It has not been a good week for me bit but I am not a dumb a**, and if they want to compare apples to apples so be it. They claim a trace of mercury in an engine for a fraction of a second "IF" it happens destroys and then they show a video of a "TIME LAPSED" video of a large amount of mercury that clearly has taken much longer than seconds (2 hours according to description). It's like saying "Do not wash you bike with water cause if you leave the water on long enough the metal will rust". Maybe they have not handled mercury before as I have and currently have 3 pounds of it from an old dental practice. I am familiar and have used it in vials on pendulums on antique rare clocks as well as my tools. My point again is all I stated was that I used my manometers and they make me out to be doing wrong. Is that fair? Now if I make a recommendation how trust worthy can it be after they try to make me look stupid? I really was hoping to become someone who could advise and help on this forum and my area and even have altered my bike with some not so traditional changes that was recommended here so I could confirm how they worked for me. I have been careful with my recommendations to not steer anyone in the wrong direction and trying not to be biased as can be seen in some members (not a bad thing on venture specific site). If I owe an apology then I am man enough and apologize to those I may have unintentionally offended except to those who have tried to make me look bad. If you want me to leave the site because I made a simple post of what I used to sync carbs and my defending of my actions on my personal bike that I KNOW are not damaging as they state then I will do so at only your request. I do not want a war but I do not want to be belittled or put down as I did not sign up for this on this site. They have more seniority and may think they know all but in all fairness everyone makes mistakes and just maybe I am not wrong on this one. This is supposed to be "family" and "family" should not be destructive to each other. I respectfully await your ruling, I am really not hard to get along with but do not like to be made to look stupid when all I did was make a harmless comment about what tool I used.

Edited April 15, 2015 by Brenner

[Freebird]

Brenner,

There is no ruling to be made. It would never be my desire that you leave the site over this. There are very few people here that have not posted something at some point or another that got under somebodies skin. I agree with some of what you said but was just taken back a bit by the attitude in how it was said. I didn't feel that you should have taken such offense and went on the attack about it. Like I said, I don't know of a case where mercury was sucked into the engine and caused any damage. I tend to agree that it would just pass right through but I've never torn down and inspected an engine after that has happened so I can't say with 100% certainty that there was absolutely no damage. The point is, it was just another opinion and a different viewpoint. I honestly don't think it was meant as an attack against you or your choice of tools.

 

Now the readers can make their own decision about which tool is best for them. Many user the Mercury sticks, many use the Carbtune. Some HATE the Carbtune and don't trust it at all. I used the Carbtune for many years and it did a good job. I'll be the first to admit though that if not kept clean, the rods can stick and cause some bad readings. So there are positives and negatives to both.

 

At any rate, I am not wishing for you to leave and hope to see you hear for many years. You input here has been very helpful many times.

[syscrusher]

However, I thank friesman for his post, letting me know the potential dangers of using mercury manometers.

 

 

I was shocked and amazed by that video. It is common knowledge now how toxic mercury is to people. I remember as a little kid when a thermometer broke and my mother let me put the mercury in a small bowl and watch it spin around when I shook the bowl. I would jab it with my finger and it would amazingly reconstitute into a ball. I'm surprised I didn't try to taste it or something. I may have ingested some just by getting my fingers into it. The bottom line is that if you don't really need mercury then you really don't need mercury. Stay away!

 

I don't want to pile on at all but it just didn't appear to me that anyone was exceptionally harsh about "old school" methods. I learned a lot from reading this thread without judgement. To me that's a good part of what the site is all about, learning from others who may have a different background or experienced situations before. People usually tend to use what they already have, that's working for them. That's fine, but if there may be real issues with those methods then it wouldn't be right to not mention some of the downsides for those of us who are trying to learn about maintaining our bikes.

 

I do have a sync tool that is electronic, digital, and very accurate. I recommend it to anyone who doesn't already have another device but may be looking to acquire one. It's more of a project right now than a product because you have to source the parts and put it together yourself but it's easy to do.

 

Here's a thread about the digital carb sync project.

 

 

 

[BlueSky]

I think the video of what mercury does to aluminum is a useful and interesting post. Brenner, I don't know why you took offense to it. I'm sure nobody intended to offend you. And as far as using a mercury manometer, if they were still available that would be the one I'd buy. As heavy as mercury is, it makes an ideal liquid for the carb sync.

Edited April 17, 2015 by BlueSky

[Brenner]

Bluesky, I am trying to let this issue go and once again will politely state that my beef was that someone posts a video that is time lapsed and says that I destroy engines with this tool which is not related to what I posted in my opinion is an attack. I am not arguing that mercury is something that must be handled with respect as it is dangerous but rather in a controlled environment (the manometer) when used correctly and responsibly as intended it is a hard to beat tool. Mercury does not expand and contract with temp, it does not leave a film or residue in the manometer tubes so it can be read quickly and accurately. I am sure the poster of the video and many of our members who have fillings from dental work have had contact with mercury. I am sure unknown to them the mercury I use is caulk mercury from a dental office used in the process of making amalgams and alloys for dental repair. I had access to it and it is purified so why would I not use it? This stuff even today is not cheap, hatd to acquire, and it is a quality product. You are right it is the tool I have and it is tried tested and true if respected while being used and I have used this over 20 years and no damage and will not lend it out. Regarding my beef, lets do the math : the video posted is time lapsed over 2 hours according to the description on you tube of which it came. Now our bikes are supposed to be synced at roughly 1000 rpm ( our tach might be a bit off one way or the other) so that means a single cylinder in this engine reciprocates 16.6666666 times per second and I'll round up to 17 revolutions per second for easy numbers. Can anyone honestly say that trace of mercury accidentally contacting an engine component during combustion process for a 17th of a second during a carb sync do the damage shown in a 2 hour video of a large amount of mercury on a stationary object? So my point is why would someone use that video when it does not directly relate? I suppose it is the only one available to make their point or maybe they did not consider the other factors I have mentioned. venturesome has requested an apology from me and has called me arrogant, and my reply is that I maybe so but for a reason in which I can back up and when one is challenged or vilified is it wrong to defend oneself? If it happened to you would you apologize and make the other look correct when clearly they are not? I would not fight if their point was valid and accurate to my original post. I have not heard a response about the timing of the video, and perhaps it is not needed as it proves I am correct. Accurately show me I am wrong and I will apologize openly and publicly as we all make mistakes. I have been told this forum is for respectfully sharing opinions but this has proven it otherwise when one as myself am thrown under the bus for a tool I use and demonstrated in an inaccurate timeline video. Okay, please no more trouble over this, time to let it go, I just compare apples to apples, and time length to time length, and reactions to reactions before I make replies and I wish others would respectfully do the same. Every family at times has bumps in the road let's not have this steer us in the wrong direction any further and thank you to those who have shown support on my side of the disagreement.

Edited April 17, 2015 by Brenner

[Prairiehammer]

time to let it go,

 

Yep, agreed.

 

(And I use a mercury manometer).

[Brenner]

Yep, agreed.

 

(And I use a mercury manometer).

 

Thank you my friend.

[cowpuc]

Hey Wolfy, take a quick peek at the bottom of your gauge rack where the hoses connect onto the guages and see if the hoses are connected to a nipple that also serves as an adjustable flow restricter - I had an old set that had em (my newer gauge rack has em but they are knurled and easily noticable) and unless you knew they were there you may not even realize the gauge rack had them - never know, might be worth a look.. If nothing else,, it sure seems like 4 of those cheapy little plastic inline fuel petcocks could be adapted real easy like,, or,, how about an aquarium air bubbler flow restricter - turn the knob to adjust the flow..

[Vonwolf]

Here is a picture of my synchronizers with some valves I got from Home Depot, they're old, dirty and rusty, but they do work. I think the valves will calm the needles down, I managed to break one already and I'm having a rough time finding 1/4" hose clamps so I'm still in the theoretical stage. One way or another I'm going to get these things working today I don't care how many Auto Parts Joints I have to go to, I finally got my Truck running right so now I can put all my energy in the bike. I might ditch the Homer Valves and try to find those restrictors vidioarizona posted back in post #7 , I have to put some miles on my truck to make sure the codes don't come back anyway. Thanks for all the suggestions and cowpuc I just might visit some pet stores as well as a backup to a backup plan.

 

[Prairiehammer]

The only flaw in my plan is the 1 gauge that doesn't bounce at all, I tested it on Carb #1 and #2 they both were steady so there's something strange going on with that gauge. I just hope it gets me close

 

While you are at the auto parts store, pick up a five-way vacuum manifold or splitter. Connect a source of vacuum (a Mity-Vac is ideal) to one nipple and your four gauges to the other nipples. When you apply vacuum to the splitter, all gauges should read identically. If not, then perhaps there is some adjustment capability on the gauges.

[Vonwolf]

While you are at the auto parts store, pick up a five-way vacuum manifold or splitter. Connect a source of vacuum (a Mity-Vac is ideal) to one nipple and your four gauges to the other nipples. When you apply vacuum to the splitter, all gauges should read identically. If not, then perhaps there is some adjustment capability on the gauges.

 

 

[ATTACH=CONFIG]98881[/ATTACH]

That's a good idea thanks, I'm not really confident with this unit. I tried to use it today but to get the needles to stop bouncing I just about had to shut the valves off completely to the point I was hardly getting any vacuum showing at all. I got them close to each other and the motor was running pretty well, but it was popping when I revved it up and let off the throttle. I know I'm getting spark to all the cylinders but I don't think all 4 are firing all the time because the exhaust pipes are different temperatures. I'm not real confident with this synchronisation and that could be the problem, but the TCI is looking kind of rough, I don't know much about what they control but I'm a little suspicious of it. I know nothing of this bikes history so god only know when the valves were last adjusted and that could be a reason the vacuum is bouncing so bad, I think I have my work cut out for me.

[Condor]

Found this at Auto Zone. Probably other sources as well.

http://www.autozone.com/fittings-and-hose-line-connectors/vacuum-connector-and-tubing/dorman-autograde-3-16-in-dia-hard-vacuum-tubing-restrictor-connector/369702_0_0/