Carb Syncronization Tool/Method?

Happy new year! Take care, stay safe…
I have thoroughly cleaned, statically syncronized and installed my carburetors.
Now I want to hot sync them while the bike running.
BUT… I can not reach the sync screw of #2 carburetor with L-Type carb. adjustment screwdriver due to interference with coolant pipes.
Can are any one recommend the best tool/method to reach this "ingenious’ location.
Thanks for worked out solutions.

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My brother and I worked out that the only way to reach that front screw was for one of us to partially open the throttle with the twistgrip while the other adjusted the screw - this was using the Sealey type 90° ended adjusting tool. As you say, there’s a pipe in the way with the throttles shut. There’s a fair bit of messing about to start with, but once you’ve worked out which way to turn it to get the vac gauges moving in the right direction, you can get it right. Bit of a pain kepp stopping and starting the engine, of course.

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Thanks for great advice.
Agreed it is bit of a pain but at least this is workable method.
Thanks again

Hey this is a message to anyone who is interested in the American website dedicated to V4Muscle Bikes.
They have a great discussion page and also are full of info about the V4 Machines. In relation to a carb syncronisation tool there is an article that shows you how to make one that actually works. For anyone interested go to “” and click on the sponsor called “The Carb Spa” on the left hand side. Go to his Thread section and find the “links to Magnandy articles” Find the link about the carb synch tool and then all you have to do is follow the instructions. There’s heaps of other articles as well and lots more on the website. I would advise that you become a member as it unlocks more areas of interest. I have been a member for a little while and have gained heaps of knowledge from it.

Hi everyone, I have found another very helpfull website with some very helpfull information about carby rebuilds. He also sells what looks like a pretty good tool for adjusting the carbs. this website is not just for V4’s.

After tinkering with various tools, I have found that 7mm socket attached to swivel joint is the best option.
I was even able to reach the notorious #2 Carb Sycn Screw, but only by twisting the throttle to expose the stubborn one, as advised by Pete.

Here is the photo of the tool that worked for me:


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