I bought the 4 cylinder vacuum balancer to balance my 4 cylinder 4 stroke carburetted Mercury outboard, because my service guy only had the old mercury tube balancer and wasn't very successful.
The Raytech balancer was a delight to use, noting the carbies were WAY out of balance after an overhaul, and now the engine idles and performs like the day I bought it!
Only downside is you can't read the LED display outside in the sun, but I worked around that.
This device completely takes the mystery out of balancing the carburettors. I did mine in about 20 minutes from start to finish, away from the workshop, on my v-twin. Looking forward to doing my triple and eventually, when it is restored, my vintage 4-cylinder GPZ..
I previously brought a cheap carby synchronization tool online when I went to use it only one guage out of the 4 would sit still the dampener was no good on the rest making it impossible to use. I then went and brought a synchronizer from ray tech automotive I was nervous buying one after the last one. I tried it out straight away and was blown away by how easy it was to use and how accurate it was compared to the last one.
My motorbike is now tuned in a lot better and I was very happy with the product.