Carb syn'ing with a synrometer

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LC Cnd
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Carb syn'ing with a synrometer

#1 Post by LC Cnd » Mon Jan 01, 2018 8:13 pm

Just got this Vacuum Mate TS71 to do my carb syncing as apposed to the popsicle stick method. Just need to find a set of frost plugs to attach the hose lines 1&2 for the intact end of the carbs. Never used one before but look fwd to see how it works out now that I found a youtube vid on the Vacuum Mate. Found another vid that shows you how to use a carb syn (dial type) and adjust your carbs to sync them. Demo is on a banchee (Cool head?) motor. Be interesting to hear what my LC motor/carbs sound like in sync and rd test it come Spring.
https://www.youtube.com/watch?v=hZ6EeABS3gk" onclick="window.open(this.href);return false;
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hondaror
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Location: Alberta, Canada

Re: Carb syn'ing with a synrometer

#2 Post by hondaror » Mon Jan 01, 2018 11:23 pm

You will like the results.

Can you say super smooth?!
Rory
2 1984 RZ350s
1985 RZ350
9 1986-1990 RZ350s
2000 ST2
2005 749
2005 749 with 999 engine

LC Cnd
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Posts: 1454
Joined: Sat Feb 08, 2014 5:39 pm
Location: Vancouver Is. Canada

Re: Carb syn'ing with a synrometer

#3 Post by LC Cnd » Sun Feb 04, 2018 10:41 pm

Found a couple of beer bungs (#9's) to fit the intakes and fittings for the tubes back to the carb sync. The only thing is Rory with this set up I don't think there is enough air volume going into the carbs for readings while the engine runs - would you agree?. What another possible solution?
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hondaror
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Re: Carb syn'ing with a synrometer

#4 Post by hondaror » Mon Feb 05, 2018 2:36 am

You're right about the air. Your engine will not run. That unit is for a 4 stroke with intake access. You'll need to buy a unisyn.
You could drill the carbs and install bungs on the intake track, barrel side, but that sets you up for "other" air leaks and possibly other problems.
Roughly $80 gets you the unisyn.
Rory
2 1984 RZ350s
1985 RZ350
9 1986-1990 RZ350s
2000 ST2
2005 749
2005 749 with 999 engine

LC Cnd
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Posts: 1454
Joined: Sat Feb 08, 2014 5:39 pm
Location: Vancouver Is. Canada

Re: Carb syn'ing with a synrometer

#5 Post by LC Cnd » Mon Feb 05, 2018 10:34 pm

K, got one. Did the gent in the noted youtube link do use it correctly. Appears to be a lot more room on a GT750 than on a RD to use it - not that it can't be done.
https://www.google.ca/url?sa=t&rct=j&q= ... a5XTA2fDPc" onclick="window.open(this.href);return false;
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ZedSledder
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Location: Vancouver Island British Columbia
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Re: Carb syn'ing with a synrometer

#6 Post by ZedSledder » Tue Feb 06, 2018 12:18 am

What about the Dellorto one the guy on South Texas Banshee uses? Might have to sync the carbs then install the airbox? I’m not sure, just putting it out there? So far I do the window for open throttle and then the throttle stop and it ran, I went with it.
In laymans terms if South Texas Banshee can tune carbs with those catchers mitts ,anyone can.
Yes Spring is here on the Island, and we are rideing.
1985 Canadian Rz350. Restored with collector plates. Stock VM26, Triumph Calipers, Galfer brake lines. Brand new DG’s, 260 main, 22.5 pilot jet. Economy pre-load adjusters. Ohlins shock. Oem Banshee crank.

hondaror
Posts: 2828
Joined: Mon Mar 03, 2014 8:44 pm
Location: Alberta, Canada

Re: Carb syn'ing with a synrometer

#7 Post by hondaror » Tue Feb 06, 2018 3:13 am

You should be able to remove the air box rubbers to access the carbs. If not, remove the air box. (Not fun).
You want to set the idle, and check the vacuum on both carbs. They must be set the same. Use the idle adjustment screws to set them the same at idle. Now you need help from a friend. Someone needs to hold the throttle steady at about 3,000 rpms. By checking the vacuum at this rpm you are ensuring that the slides are advancing at the same time. This adjustment is tweaked with the throttle cable adjusters at the top of the carbs. Again, you want to match the vacuum of both cylinders. You will have to adjust the unisyn flow to read the floating ball. Finally, after shutting the bike down, twist the throttle wfo to be sure the slides are completely up in the carbs.
Every time you change a screw or adjuster setting, you need to blip the throttle to allow everything to settle down to the new adjustment. When everything matches up, you're done.
The bike will run way smoother. You should notice that.
Rory
2 1984 RZ350s
1985 RZ350
9 1986-1990 RZ350s
2000 ST2
2005 749
2005 749 with 999 engine

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