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Mercury used to be in everyones homes. And is still in many homes today in the thermostat. nice to know huh.
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homemade carb sync ?
- Thread starter WacoBrian
- Start date
mistercartoon
XS650 Enthusiast
Does any1 know how the mercury was used in the felt hat indusrty?
im as bloody mad as a hetter! but mad with a sync set of carbs!!!
i put a pair of stock xs 135 jets between the 2 sizes of clear tubing & worked a treat.
the right side carb (kickstart side) i found to be far more adjustable than the gear lever side carb.....any thoughts on that? i had the left side near all the way wound out, syncd the right side carb & just couldnt slow down the revs as much as i wouldve liked.
its a stock 650...assuming these brand new carbs from 650 central have stock jets, would jetting up or down be worth a bash?
thanks a lot for the help, im pretty bloody happy with the outcome!
im as bloody mad as a hetter! but mad with a sync set of carbs!!!
i put a pair of stock xs 135 jets between the 2 sizes of clear tubing & worked a treat.
the right side carb (kickstart side) i found to be far more adjustable than the gear lever side carb.....any thoughts on that? i had the left side near all the way wound out, syncd the right side carb & just couldnt slow down the revs as much as i wouldve liked.
its a stock 650...assuming these brand new carbs from 650 central have stock jets, would jetting up or down be worth a bash?
thanks a lot for the help, im pretty bloody happy with the outcome!
Wasn't sure where to put this, so stuck it in here.
I don't use vacuum gauges or manometer to sync, but would like to humbly offer a revision to the fluid type manometer design in use by others.
The issue of sucking the fluid into an unbalanced cylinder can be solved by adding a pair of large-volume reservoirs to the top of the contraption. If a cylinder pulls too much vacuum, the fluid will simply enter the reservoir, air will bubble thru it without entering the engine. The volume of the reservoirs should each be at least twice the volume of the working fluid.
I'll leave it to the members to come up with suitable reservoirs.
Edit: Meat marinade injectors and basting syringes come to mind.
Edit2: The volume of fluid, as shown in the above pic, 3 feet in a 3/16" tube, will be close to 15cc...
I don't use vacuum gauges or manometer to sync, but would like to humbly offer a revision to the fluid type manometer design in use by others.
The issue of sucking the fluid into an unbalanced cylinder can be solved by adding a pair of large-volume reservoirs to the top of the contraption. If a cylinder pulls too much vacuum, the fluid will simply enter the reservoir, air will bubble thru it without entering the engine. The volume of the reservoirs should each be at least twice the volume of the working fluid.
I'll leave it to the members to come up with suitable reservoirs.
Edit: Meat marinade injectors and basting syringes come to mind.
Edit2: The volume of fluid, as shown in the above pic, 3 feet in a 3/16" tube, will be close to 15cc...
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Have any of you used this type of manometer?
I tried using it with colored water. I hooked it up after trying to sync my carbs by ear, and the vacuum was so great that it ended up crushing the bottles and raising the water level to the capability of drawing it up into the right cylinder. It only passed a little through and I shut it off quickly.
The fact that it crushed the bottles is pretty surprising to me. I've watched a few YouTube videos of people using this very build and their bottles didn't deform like this. Is there such thing as too much vacuum?
I've lowered the water level and I'd like to see it work, but I'm leary about sucking water into the carb again.
I tried using it with colored water. I hooked it up after trying to sync my carbs by ear, and the vacuum was so great that it ended up crushing the bottles and raising the water level to the capability of drawing it up into the right cylinder. It only passed a little through and I shut it off quickly.
The fact that it crushed the bottles is pretty surprising to me. I've watched a few YouTube videos of people using this very build and their bottles didn't deform like this. Is there such thing as too much vacuum?
I've lowered the water level and I'd like to see it work, but I'm leary about sucking water into the carb again.
Attachments
racerdave
^ Gone not forgotten ^
Try putting a vent hose in the cap, that you can restrict it's opening. Are those water bottles? A pop bottle may be a little stronger?
A u-tube manometer with such light-weight fluid should NEVER be used until AFTER doing a bench synch to get the two carbs close. Otherwise, unless it's pure luck that they are close, it is quite likely that the vacuum on one side or the other will be enough stronger to pull fluid up out of the manometer and into the engine. There are many ways to do a bench synch; it is not difficult to understand or accomplish. The u-tube is for a final "trim" adjustment.
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To keep your fluid from pulsing so much add smaller orifices. Mikes pilot jets are perfect for that job. To keep from sucking the fluid into the motor add a valve on one side.
Only open it(the valve) after the motor is running and you are ready to shut the valve or hit the kill switch.
Only open it(the valve) after the motor is running and you are ready to shut the valve or hit the kill switch.
I have to agree simplicity is the key..... its not rocket science
I have always used a length of plastic tube and listened to each carb intake to sync and tune my carbs. These days everyone seems to need a tool or gadget to do most everything
This works...I have made a set, but I used "Starbucks" larger glass coffee bottles (The kind with a wider mouth) so it can take the pressure, then I got rubber cork stops at Lowes, drilled out the holes, inserted the hoses and done.
The key to this type is to fill only one bottle with fluid, and below the hose that goes to the vacuum port, then balance that amount out between the two bottles...so that even if one side pulls all the fluid, it CANNOT get out into the line going to the vacuum port. Also, I recommend using a heavier fluid...like ATF. Water will work, but it just moves really quickly.
I have since switched to the other style, with a yard of aluminum tubing as the frame, and creating the U shaped tubing held on with zip ties. This I hang from the rafters just above the bike and I have really long lines (at even lengths) going to the ports... so that I have plenty of time to shut it down if need to. So far, I've not needed to put any restrictors to limit the vacuum pull... and it's worked great.
However, as said before, a good bench sync is important so you're not chasing the sync drastically from the start.
You guys are mad and have way too much time on your hands making these cumbersome sets of gauges, I purchased carbtune gauges about twenty years ago and they have more than paid for themselves, well worth the $80 I paid for them, and over the years they have only gone up in price by about $10.
Ha ha... well I suppose it could be seen that way, but I like to tinker and build things if possible. It's fun! Cost/value? That's all about perspective.
Cost in $ and time:
For me, I had the tubing, had the aluminum, had the zip ties... didn't really cost me a dime. I suppose if I were to buy those off the shelf specifically for this project...the tubing would be around $5.00 and the aluminum would be around $10.00 and the zip ties a few bucks...so $18 + Tax?
Regarding time, it took me less time to put it together and connect it than it would to open a store-bought package, read the instructions and get it on the bike.
It's all good either way!
Does any1 know how the mercury was used in the felt hat indusrty?
im as bloody mad as a hetter! but mad with a sync set of carbs!!!
i put a pair of stock xs 135 jets between the 2 sizes of clear tubing & worked a treat.
the right side carb (kickstart side) i found to be far more adjustable than the gear lever side carb.....any thoughts on that? i had the left side near all the way wound out, syncd the right side carb & just couldnt slow down the revs as much as i wouldve liked.
its a stock 650...assuming these brand new carbs from 650 central have stock jets, would jetting up or down be worth a bash?
thanks a lot for the help, im pretty bloody happy with the outcome!
Mercury was used to aid in the release of the hair from the animal skins and the vapour from the mercury made the hatters mad to coin a phrase,
I myself in 1985 managed to ingest some mercury and boy was I ill within 2 months my body had lost almost a hundred pounds in weight, it took two years to get back on my feet and I have never fully recovered, thank goodness I was working for an American company as they took good care of me and compensated me nicely, had it been a British company I would still be fighting them. I have since had all the mercury amalgam removed from my teeth as this also leeches methyl mercury into your bodies.
Still the manometers you guys make may work well but still way to cumbersome fro my liking.
Bob Kelly III
Ranch Kid from way back,.... that got Old !
2M : Thank you for the link to your design ! I can see that the U tube idea is very sensitive because any imbalance would pull the liquid to one side
.... another method would be the vertical idea of just one jar ( with a vent) and a tube into it through the top lid.... and at the top of the tube have another jar for the resivour to catch the fluid should it go too high.... now this is just one side , a stand alone vaccuum meter...
make another for the other cylinder and you would have a carb Syncer.... the problem with this design is making sure there are no restrictions in the
design ( where the tubing goes through the lids) so drill the hole through the lid and Hot glue it in place.
this way it's not so touchie as to mandate you sync the carbs with a piece of paper FIRST.... (if your going to do that it's already purty darn close anyway)
and there is no danger of sucking the liquid into the engine because of the resivours at the top......
no valves or jets needed just hose/clear line and 4 small jars or cans....
simply plug the end of the tube into the intake port and start her up .... adjust the sync so they are level and ya have it ....
.... the reason I like this design is because it is less sensitive than the U-tube idea.... its vaccuum against the small weight of the liquid , on each cylinder
indipendant of the other cylinder.... where as the U-tube idea the vaccuum connects in the middle and the vaccuum fight each other to move the liquid
this may well be the most sensitive method, but do we need it THAT SENSITIVE ?....I don't think so....
......
You guys have exceded my expectations ! thank you !
....
Years back there was a carb syncer that was 4 vaccuum guages on a rack with plumbing and valves for each guage.... the idea was to set the guages on one cylinder and adjust each guage to the same mark with the valves . then hook them up and adjust the engine....
I have hurd that they wern't very accurate but the shop I worked in used them for years so they must have been close enough!
....
Bob.....
.... another method would be the vertical idea of just one jar ( with a vent) and a tube into it through the top lid.... and at the top of the tube have another jar for the resivour to catch the fluid should it go too high.... now this is just one side , a stand alone vaccuum meter...
make another for the other cylinder and you would have a carb Syncer.... the problem with this design is making sure there are no restrictions in the
design ( where the tubing goes through the lids) so drill the hole through the lid and Hot glue it in place.
this way it's not so touchie as to mandate you sync the carbs with a piece of paper FIRST.... (if your going to do that it's already purty darn close anyway)
and there is no danger of sucking the liquid into the engine because of the resivours at the top......
no valves or jets needed just hose/clear line and 4 small jars or cans....
simply plug the end of the tube into the intake port and start her up .... adjust the sync so they are level and ya have it ....
.... the reason I like this design is because it is less sensitive than the U-tube idea.... its vaccuum against the small weight of the liquid , on each cylinder
indipendant of the other cylinder.... where as the U-tube idea the vaccuum connects in the middle and the vaccuum fight each other to move the liquid
this may well be the most sensitive method, but do we need it THAT SENSITIVE ?....I don't think so....
......
You guys have exceded my expectations ! thank you !
....
Years back there was a carb syncer that was 4 vaccuum guages on a rack with plumbing and valves for each guage.... the idea was to set the guages on one cylinder and adjust each guage to the same mark with the valves . then hook them up and adjust the engine....
I have hurd that they wern't very accurate but the shop I worked in used them for years so they must have been close enough!
....
Bob.....
Using vacuum gauges was and is a very bad idea. They are not very accurate and expensive as well. Just because a motorcycle shop used vacuum gauges, does not mean they worked very well. I'd say a lot of their customers had carbs with a poor synch, and most of the customers wouldn't even know the difference.
Also your idea of 4 jars and 2 independent measurements is cumbersome and again not very accurate.
The whole idea is to keep it as simple as possible.
Also your idea of 4 jars and 2 independent measurements is cumbersome and again not very accurate.
The whole idea is to keep it as simple as possible.
angus67
Welder's penetrate deeper!!
Mine with atf.
Ditto. Just to give folks an idea of the relative accuracy difference between the gauge and manometer, consider this gauge set:
The full sweep, from atmospheric to complete vacuum, 0-30 on the scale, is about 220° of needle movement. On a 3" gauge, the circumferential needle tip travel is about 4.5".
Using a clear tube manometer, with ATF as the working fluid, the full travel from atmospheric to complete vacuum would be about 45 feet.
Expanding that 4.5" needle travel range to 45 feet of ATF travel range is a magnification of 120x.
Edit: And, if you look closely at that brand new gauge set, you'll notice that the needles are pointing differently by about 1mm . That tiny 1mm needle offset would be about 5" on the manometer...
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Bob Kelly III
Ranch Kid from way back,.... that got Old !
2M:......Ok . Here's my thoughts....in the Manometer the idea is to draw the liquid up the tube against the pull of gravity....it would need to go a long way to reach -30pounds of vaccuum.... But the U tube Manometer doesn't work like that, Its not measuring vaccuum per say it's measuring the diference between 2 vaccuum points because the tubes are connected at the bottom of the "U".... If the tubes were seperate and had their own resivour then they would be the same, measuring the amount of vaccuum for each cylinder seperately.
the interesting thing is , that it's not nessarry to measure the Vaccuum on each cylinder. Only the diference between the 2 cylinders is needed.
so the "U" tube idea works very well for what it was designed for . but it's use is technically diferent.
.....
Bob........
the interesting thing is , that it's not nessarry to measure the Vaccuum on each cylinder. Only the diference between the 2 cylinders is needed.
so the "U" tube idea works very well for what it was designed for . but it's use is technically diferent.
.....
Bob........
angus67
Welder's penetrate deeper!!
with the sync I posted, you don't have to measure or guesse at anything. hook it up, and if one side is higher that t'other, adj.
Bob Kelly III
Ranch Kid from way back,.... that got Old !
indeed ! the "U" tube design is really the best thing I can see for balancing the carbs with ! very sensitive, and that's what I want
to get the carbs SPOT ON ! ......
How often do you check the carb Sync ? is it a once a month thing,.... Or once every 6 months ????
.....
Bob...........
to get the carbs SPOT ON ! ......
How often do you check the carb Sync ? is it a once a month thing,.... Or once every 6 months ????
.....
Bob...........
angus67
Welder's penetrate deeper!!
Every spring. And for the most part barely off
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