carb sync question

[walker70]

I am ready to put my carbs back on my 86 Goldwing,now I would like to know if they should be synced up or since the only things I did was install new parts in the float bowls and did not move any adjustment screws at all,in the past when I have rebuilt carbs as long as I did not mess with any adjustments on them they ran fine,thanks for any info,if I need to sync them I would like to know what type of synchronizer is best so I can get a set,I am not going to have a shop do them since it is so expensive.

[deanbw]

just rebuilding them can cause them to flow different, you may (and should) sync them. I am not saying it won't run, it most likely will, it's just that it could run better. I have had both types of tools, tubes and gauges, I like the tubes best, a little harder to store and cost a little more, but they are dead on. Gauges work ok and fit most peoples budget better, just make sure if you go that route you calibrate the gauges before using them, ( instructions show how, very simple)

[walker70]

Thanks for the reply,I will probably sync as you say but I just needed some input.

[ColdShadow]

Greetings,
If you still have the carbs off the bike there is actually a way to sync them on the bench. It's just as accurate and to me easier then gauges, since synchronization is a matter of all the throttle plates opening and closing at the same time. Using a small slender feeler gauge, I prefer .003" because its flexible, Set the main carb to that gauge, on my 1980 GL1100 it's carb #3. With that carb set go to the remaining carbs, setting then to the same gauge and drag on the gauge as the main carb. Once you have them all done actuate the linkage, recheck and readjust as required until they all read the same, Then your ready to install and set idle mixtures.
This worked very well on my GL1100, as the local dealer wanted $480.00 to sync and set mixtures, they also were going to drill into the pipes to use a gas analyzer for mixture set up. While the gas analyzer would be dead on, I didn't want my exhaust compromised.

[walker70]

Thanks for that bit of information because all the shops in my area charge about the same ,that seems to be a good idea so I might try it,now a question for you, when you set the main carb with the feeler gauge do you mean with the throttle plate closed with a slight drag,sorry if that sounds silly but I like to be clear,have got some gauges on the way as well.

[deanbw]

Thanks for that bit of information because all the shops in my area charge about the same ,that seems to be a good idea so I might try it,now a question for you, when you set the main carb with the feeler gauge do you mean with the throttle plate closed with a slight drag,sorry if that sounds silly but I like to be clear,have got some gauges on the way as well.

you can get close bench syncing but you still have to sync with bike running to get them right, it will run ok with just bench sync but you cant match the vacuum on all carbs unless it's running.

[ColdShadow]

Yes, throttle plates closed with a slight drag. Once all carbs are the same you can return the main throttle stop to Idle position. It helps to count the number of turns you backed the idle stop off of, so you can return it to a near to idle setting. Vacuum sync shouldn't be but a micro setting off.

[Old Fogey]

Try it this way (carbs off ). No risk of damaging the fragile edge of the throttle plates.
http://www.wingovations.com/synchronisi ... 4590612876

[walker70]

Hi again,thanks for all the help,now I have a question about the pilot screws,according to my Haynes manual you turn them out the amount of turns as stated in the book then adjust them again after you warm the engine for ten minutes or so,then hook a tachometer to the bike and turn the screws either in or out depending on the rpms,I would think the initial setting and synchronizing them would be fine,if I am thinking wrong,let me know,the reason I ask is because the person who had the bike before me had all the pilot screws on the wrong settings.

[deanbw]

Personally I set them to factory start point, (1-1/2 - 2 turns, cant remember what it is) I go through and sync carbs ( not bench, engine running) get that done and idle set, then I one at a time slowly turn in or each screw until I get highest idle, , turn screw back about 1/8 turn, reset idle go to next carb, do it again. Once all carbs have been done I re-check the sync and adjust if necessary, takes some time but bike will run better than you ever thought it could.

[salty1]

I agree with re-synchronization when the carbs are back on the bike. Turn your pilots out the same number of turns on the bench and leave it at that, all will be good. Fussing with rpm changes as you turn the pilots etc. is a PITA and a waste of time IMO.

[walker70]

Thanks salty1,it is a good thing I rechecked everything today because I had not really noticed that two of my pilot screws were stuck at the wrong adjustments,I was going to replace them anyway so now all is good,and also thanks to everyone for the help.

[deanbw]

I agree with re-synchronization when the carbs are back on the bike. Turn your pilots out the same number of turns on the bench and leave it at that, all will be good. Fussing with rpm changes as you turn the pilots etc. is a PITA and a waste of time IMO.

I agree 100% if all your after is for it run OK, then leaving the pilots all at the start point is the way to go. If you don't want to take the extra 20 minutes to see how it could run you'll never know the difference and all will be good......enough.

[walker70]

Hi again,my carb synchronizers came today so I can throw the carbs back on,need to know if anyone can tell me something,according to the the kit it was supposed to have the tee adjusters for, connecting to the hoses,I have contacted the company I bought them from to see if I misunderstood the description,they have not gotten back with me yet because it is the weekend,but if they do not supply them,does anyone have any ideas on where I can get them or possibly have a way of making them,thanks.

[deanbw]

Hi again,my carb synchronizers came today so I can throw the carbs back on,need to know if anyone can tell me something,according to the the kit it was supposed to have the tee adjusters for, connecting to the hoses,I have contacted the company I bought them from to see if I misunderstood the description,they have not gotten back with me yet because it is the weekend,but if they do not supply them,does anyone have any ideas on where I can get them or possibly have a way of making them,thanks.

Well, most gauge kits come with the little valves to take the bounce out if the needle, but I have to say I have not seen "T's" in any kits. I just bought a little package of them at oreilly's.

[walker70]

Sorry deanbw,I should have said valves instead of tees,that was my bad,I will check with O'reillys if the company I bought the synchronizers doesn't send them to me.

[salty1]

If you have an aquarium shop nearby, they will have an air supply valve/regulator that you can use. Can you put up a picture of the device you purchased, that might be helpful?

[walker70]

Hi,I have thought of aquarium shops for the valves,have a photo of the synchronizers,here is what I got,

[Old Fogey]

Decent looking kit. You will definitely need the valves with it. Remember to calibrate all the gauges to one vacuum source ( one cylinder) before connecting them up to all four.

[walker70]

Hi again,went to PetSmart today and got these valves,they look like they will work,cost $6.00 for a pack of five so I have a spare.

[deanbw]

Hi again,went to PetSmart today and got these valves,they look like they will work,cost $6.00 for a pack of five so I have a spare.

IMG_0212.JPG

Perfect, and probably better than the crappy ones you get (normally) with the set.

[tbeiler]

Hey, Walker70, do you mind passing on where you got the synchronizer and price paid. I am also looking to buy a synchronizer, least expensive one I could find here in Canada is about 150.00. Thx.
Oh and what are those valves called at Petsmart. Part number.

[froche]

"Hey, Walker70, do you mind passing on where you got the synchronizer and price paid. I am also looking to buy a synchronizer, least expensive one I could find here in Canada is about 150.00. Thx.
Oh and what are those valves called at Petsmart. Part number."

http://www.carbtune.com/
Includes everything!
According to an online calculator = 127.48 Canadian Dollars

[walker70]

Hello,froche,I bought the synchronizers from a company called supermotopartsfactory on their ebay store,the price for them was around $60.00 with shipping,also they are going to send me the air valves and o rings that were missing so I will have more than I thought I would,the set I got from PetSmart is a kit that comes with 5 air valves,4 y connectors and 2 two suction cups and it's made by a company called Great Choice for about $6.00,only part # I see is on the back next to the bar code,#gc-13-011.

[salty1]

I've used vacuum synchronization gear, manometeric systems, etc and spent a lot of money. They worked but by far the best sync system for the money is the DigiSync. Simple to use and as accurate as you can get IMO.

http://thedigisync.com/