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Discussion Starter #1
ok i have this 94 xlt chassis with a indy 88 650 motor in it with pipes and i need to have my carburators syncronized.

for the cost of having it done i know i could buy the tool to do it but i have never done it before and would need some advice and help on how to do it from some of you guys who have done it before.

1. is it worth me getting a tool and doing it myself.
2. what is the best tool out there or whats a good one to use.
3. how do you hook it up and what do you exactly adjust.
4. how do i know after i do it that it worked.

i havea few other questions but i will ask later.
thanks in advance for any information.
 

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dont buy the tool it works like crap anyway, use your fingers.
 

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Discussion Starter #3
how do you use your fingers. i seen one in Dennis kirk for$94 its a motion pro and it looks like a thermomiter and you can do all the carbs at the same time to make sure they are all the same. not sure how it works. like i said i have never done it before.
 

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I have always had wonderful luck with the uni sync tool. Cheap and every sledders garage should have one.


2007123172439568_3287.jpg


I am guessing when he said use your fingers he was referring to the slides pulling at the same time. You can check that with your fingers. Get 2 timed and the the third in relation to the first 2. I just stick my fingers in 2 carb throats and pull the throttle. You want them to pull at the same time. You adjust the pull at the top of the carb at the cable. Do the third when you get the first 2 to pull at the same time.

I normally
-make sure the slides are going up all of the way in the carb.
-adjust the throttle slide to all pulling at the same time
-use the uni-sync tool to do the actual final adjustment of the idle screws for proper sync-ing.
Done...
 

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Discussion Starter #5
dodger said:
I have always had wonderful luck with the uni sync tool. Cheap and every sledders garage should have one.


2007123172439568_3287.jpg


I am guessing when he said use your fingers he was referring to the slides pulling at the same time. You can check that with your fingers. Get 2 timed and the the third in relation to the first 2. I just stick my fingers in 2 carb throats and pull the throttle. You want them to pull at the same time. You adjust the pull at the top of the carb at the cable. Do the third when you get the first 2 to pull at the same time.

I normally
-make sure the slides are going up all of the way in the carb.
-adjust the throttle slide to all pulling at the same time
-use the uni-sync tool to do the actual final adjustment of the idle screws for proper sync-ing.
Done...
where can i get that uni sync tool?
 

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Discussion Starter #7
i just want to be able to do it myself and know how to do it and make sure i do it rite the first time. i dont want to blow it up lol
 

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Blowing things up is jetting and whatnot...buy it and if you can get the airbox off...you can sync the carbs!
 

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Sorry, ran out of time so I couldn't explain it, but yes, use your fingers like dodger explained, I had one of those sync tools and sold it because the little plastic ball would stick in the tube and not move, and no matter how I adjusted it when I would hold it over the throat of the carb it would choke it out, I personally would never own one again.
 

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Discussion Starter #10
i am going to get one and try it out. if it works great if not i can throw it on e-bay. is there any other than the uni syn tool?

who is a good guy to talk to on here about jetting this 650 tripple with pipes? i already jetted accordingly to spec from what bruce told me from psi racing for my pipes but i seem to have a major low end bog. or could that be my clutching? i have stock 94 xlt gears and secondary and a 88 indy 650 primary.
 

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They should have been able to give you some clutching info with the jetting specs but start a different thread...you will get more info on what you are looking for.


I do agree with Drew a bit...the tool can be a bit finicky but if you get them as close as you can with the 'ol fingers you can just stick the tool up there for some fine tuning...that almost sounded bad!
 

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whitexc said:
They should have been able to give you some clutching info with the jetting specs but start a different thread...you will get more info on what you are looking for.


I do agree with Drew a bit...the tool can be a bit finicky but if you get them as close as you can with the 'ol fingers you can just stick the tool up there for some fine tuning...that almost sounded bad!
HAHA god that made my day! "Just stick the tool up there for some fine tuning"
 

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None of my factory manuals say anything about a "sync" tool. Use your fingers to check slides at full throttle and to see if the slides are opening at same time. The "screws" (at least on round slide mikunis), only adjust idle to 1/4 throttle. After that its all in the jets.
Does that make any sense?
 

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Your close, the idle screws work up to about 1/4 throttle, then the needle, then the jet is about 3/4 throttle to WFO.
 

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Discussion Starter #15
dtmmil said:
Your close, the idle screws work up to about 1/4 throttle, then the needle, then the jet is about 3/4 throttle to WFO.
so the idle screw controls up 1/4 throttle. but why would i have a low end bog through the first qtr of the throttle?

i hit the throttle and its kinda doggish and doesnt seem to want to get goin.....but after i get it rolling and start tapping the throttle it seems to get goin fast enuf to want to take off and then it runs good. i have been through these carbs so many times i kinda have run out of things to try except sync them. which im pretty sure they are really close cause i made sure they open at the same time.
 

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slayerfish said:
None of my factory manuals say anything about a "sync" tool.
does it say anything about checking with drill bits? timing with your fingers?
don't use a sync tool and your carbs will never be spot on. Your 2 carbs are not always built the same. All the tool is meant to do is make sure the carbs all have the same air flow through them. This is a vaccum reading. I have noticed through the years that this is very important on triples. Many sleds have pulled into my drive running like crap. Pulled away running much better with only 5 min. of work with the sync tool.
For those complaining that it stalled/bogged your engine. You weren't using it right. It has an adjustable center cone that you can screw in and out to allow more or restrict airflow. If you would have opened it up then your engine would have never tried to stall. I have one that has a sticky plastic ball in it also. I just add some lube (blaster) to the tube before I use it and all is well.
 

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I use a drill bit, you know that the sled set at an idle speed, find a drill bit that is real close to the average of the carbs, that is what you use to set idle speed so all 3 are equal, then you make sure they are all going up at the same time by adjusting the screw on the cap of the carb, at the same time you are setting throttle lever slack.

you dont need any special tools, learn how to do it by feel.
i dont like that vacumme gauge becuase not all thing are equal in the cylinders to each other, one cylinder might have slightly better pipe than the other cylinder and that can affect the vacumme gauge. on a trail sled you will notice no difference of setting them with a drill bit vs the vacumme gauge.

go to slednutz.com and the how to section, look up setting chokes by me and sync carbs by me.
 

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Discussion Starter #19
madcow said:
I use a drill bit, you know that the sled set at an idle speed, find a drill bit that is real close to the average of the carbs, that is what you use to set idle speed so all 3 are equal, then you make sure they are all going up at the same time by adjusting the screw on the cap of the carb, at the same time you are setting throttle lever slack.

you dont need any special tools, learn how to do it by feel.
i dont like that vacumme gauge becuase not all thing are equal in the cylinders to each other, one cylinder might have slightly better pipe than the other cylinder and that can affect the vacumme gauge. on a trail sled you will notice no difference of setting them with a drill bit vs the vacumme gauge.

go to slednutz.com and the how to section, look up setting chokes by me and sync carbs by me.
will do thanks again madcow
 

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I am not saying my way is better than the tool, its just a simple way for the average guy to do it without needing to spend money.
 
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