carb sync question

[Clint]

Has anyone tried a homemade carb synchronizer? Made from clear tubing.if so does it work?

 

[dirtdigger]

It will work. Its just a basic manometer. The key is you have to have a restriction in the line connected to the engine to dampen the liquid movement. You should have one for each cylinder so you can adjust all 4 at the same time and watch the affects of one cylinder on another.

 

[Clint]

Would the fittings restrict it enough? Like the elbows t's and whatever I use to connect to the carbs

 

[dirtdigger]

I would put something in the line, the Honda carb adapters for checking the sync have built in restrictors about the diameter of a needle. Depending on the design of the manometer, fluid used, amount of fluid in the tubes, etc you run the risk of sucking all the fluid into the engine while it is running. The restrictors also dampen the vacuum pulses created by the engine running and give it a smoother consistent vacuum pull. I use a block with guages and adjustable dampers. The guages are nice because they will show vacuum bounce and can be used to diagnose engine problems etc. We talked about vacuum gauges on here before about a year ago, might want to do a search on the site.

 

[Clint]

Ok thanks

 

[Clint]

Is the set screw a 5mm? And where do I get something to adapt to a1/4" hose

 

[pidaster]

I tried a homemade unit years ago. It worked but it kinda sucked. Gauges would have been better. Last time I had to do it I found this Motion Pro unit on sale for about $35 at Cycle World. Somebody had opened it and sucked the fluid out. I put new fluid in and it worked like a champ for me.
http://www.amazon.com/Motion-Pro-08-0411-Syncpro-Carburetor/dp/B000K7JHWA/ref=sr_1_1?ie=UTF8&qid=1366339824&sr=8-1&keywords=motion+pro+carb+sync

 

[Clint]

pidaster Thank you.that directed me rite to the pieces I needed

 

[Lechy]

I use a simple "U" tube manometer to synch the carbs on both my bikes. I had 2 5x1mm screws beheaded and drilled 1mm. Use the copper washer and a lock nut to secure, some insulation tape around the adapters to ensure a seal. Cylinder #2 is the benchmark, synch #1 with #2, then synch #3 with #4, finally hook up to #1 and #4 to bring both left and right banks into harmony. You don't need to hook up to all 4.
Most folks find this difficult to understand so, the 4 carbs are not connected together #1 & #2 are connected together, #3 & #4 are connected together so you have to imagine the 4 carbs being separated into 2 separate banks. There are 3 adjusting screws, the left hand one synchronizes the 2 left hand side carbs, the right hand one synchronizes the 2 right hand carbs, the center one brings both left and right hand banks into synchronization. It is best to use 2 stroke oil just in case some gets sucked into the intake.