Review on ALPHA MOTO Universal Motorcycle Vacuum Carburetor Synchronizer Synchronization Balancer Carb Sync Balancing Gauge | Compatible With Honda Yamaha Kawasaki Suzuki GS KZ XS CB 550 650 750 850 900 BMW by Ray Mcknight

Good price. Worked very well, followed instructions for calibrating gauges and adjusting throttle valves. As the instructions and reviews say, be sure to calibrate. The calibration screw is a very handy feature. TIP: For greater accuracy after initial syncing, attach each sensor to the same cylinder while riding the bike and set each to the same reading, then reconnect each to the appropriate cylinder and make final adjustments . This moves any measurement error (if any) to the opposite end of the range you're using, meaning any measurement error will show up at zero instead of at the vacuum reading you're using. The restrictive holes on the vacuum port taps are also a nice feature, allowing you to turn off the gauge while the bike is running without stopping it.