The Digi Sync 4-CHANNEL Digital Carb Sync Tool | Digital Vacuum Gauge | Works on 2, 3, or 4 Carbs or Throttle Bodies | Easy to Use | Improves Power & Fuel Economy | Made in USA

Very easy to use and the tachometer feature is great for the older bikes I play around with.

It is expensive for sure, but holy smokes did it make carb syncing so much easier and faster. I have (which wont be for much longer now!) a Motion Pro manometer that I could never get to work properly because one cylinder would always shoot through the roof for some reason. With this Digisync, I spent more time getting the engine up to temperature to do the sync than it took to do the actual sync. Seriously, it took less than 5 minutes from turning on the device (to do the self-calibration), to me having all the carbs dialed in. I just checked and noticed that the Motion Pro is over $150, and when compared to this device, which I paid about $260, which is more than it is listed for now that I am checking again (annoying), but it is still totally worth the extra! The self-calibration is totally worth it, so is the tank mount and not trying to hang a tool off a handlebar and trying to read the pulses in fluid. The only thing I had trouble with was figuring out how to turn it off. You have to hold down the power button for about 1/2 a second. Shorter and it wont register the shut down request, any longer and it will change some settings (auto off, and units).

Expensive, but Sooooooo worth it. I have an old GS750 and these bikes are notorious for being difficult to balance and sync. Cheap vacuum dial gauges bounced around so much that it was virtually impossible to use them. This thing auto calibrates every use. Plugged the vacumn tubes onto my port extensions (from the old dial gauge set) and this unit worked perfectly. Very little bouncing around (the digital display cancels out a lot of the noise). Love it !!!! Note: this unit does not come with the brass port extensions. If you need them for your bike set-up, be sure to pick some up beforehand.

If you want the best possible carb synchronization this is it . I tried those 4 round gauges and they will get it roughly synchronized. Then I bought a carb tune and that was better but not as good as this product. So I purchased this digital carb synchronizer and it will get the carbs more in synch than anything else will. I think seeing digital numbers next to each other helps as well because the analog gauges can show different readings depending on the angle you view them where this is a number that isn't affected by what angle you view them. For the heck of it I switched the hoses all around to prove these are accurate and calibrated to a high degree. This product senses the peak vacuum signal instead of an average signal through a restrictor like the others and that makes it more accurate as well. It's worth it for sure.

As some other people commented, this carb tuner has totally been a great purchase to bring my bike from a hit or miss carb tune up to 100 percent tuned! Before this I used to rely on overall feel or ear to how my carbs should sound. My older 1984 VT750C Shadow was hesitant to start and idle felt like the front cylinder had issues. After plugging this tuner in I had my bike in sync in a minute! Wow, now that's something to be said how this simply works! It's super easy to use also, just unscrew the vacuum screws on your engine, screw in one of the included brass screws and attach the hose to it and the tuner then turn your adjustment sync screw for your carbs and that's it! I will add this to future users, do not screw the brass screw that's included with a socket or wrench! As I found out by slightly tightening it the brass screw sheared off with a piece stuck in my cylinder. I easily removed the part luckily. My advice is finger tighten the brass screws in and attached the vacuum hose. I reached out to support and within minutes I was given details how to purchase more screws at a very reasonable price and shipping to Canada even!