Correct sag adjustment is the first step in having a properly handling dirt bike, and there are plenty of products on the market that help us achieve this goal. While most of those tools are analog and my even require some math, the Motool Slacker is aimed at making the sag adjustment process as simple as possible.
The whole kit includes the main unit that houses a hook-ended cable and reads the sag in millimeters, a clamp for your rear fender or numberplate, and a remote display and connector cord. You mount the main unit to your axle via a magnet that is so strong that when I went to unscrew the battery compartment lid, I had a hard time keeping my screwdriver away from the magnet. Then you attach the clamp to your bike, extend the retractable cable and hook it to the clamp, then hit the button on the main unit to zero the measurement. From there you simply take the bike off the stand, hop on, and read the display.
To make this a one-person operation, the Slacker comes with a remote display that is connected to the main unit via a cord that is long enough to put the display on the handlebar. The tool seems to be very sensitive as the slightest movement would change the reading on the display. But, once I got into the proper riding position the display would settle on one measurement. To check the accuracy of the tool, I set the sag of my bike to 105mm using the Slacker then used a friend and a traditional sag tool to measure the bike’s sag, which was right around 105-106mm.
The only issue I had was with the clamp that goes on your numberplate. I couldn’t get it tight enough so that it wouldn’t rotate when I hooked on the cable. It’s not that big of an issue since the shape of the clamp allows it to rest against the edge of the plate, but if you have a bike with weird shaped number plates, you will have to use tape to hold it in place.
I'm impressed with how the Slacker works. You do have to be super still on the bike to get an accurate reading, but that also shows how precise it is. The magnet is crazy strong and is the same diameter as most axles so it makes it easy to make sure the unit is centered. Also you have to make sure you have almost buck and a half in your bank account, because this baby ain't cheap. –Sean Klinger