Every now and then you may find that you need to readjust the chains back to a known position. This could occur if you power/connection issue and the controller lost it’s position, had a chain skip, took apart something for some reason, etc… Fortunately, there’s a way to reset the chains without a lot of work.
During calibration, after you set the sprockets vertical, you extend the chains out to reconnect to the sled. If your “Extend Chain Distance” is a multiple of a full revolution of the sprocket (i.e., 63.5 mm for a stock sprocket), both sprockets should end up with the same tooth back at vertical. Note: see @dlang’s comment below. Take a permanent marker and mark on the link that is sitting on top of the vertical tooth of each sprocket. I’ve heard some people have used nail polish, but so far a permanent marker has remained permanent enough for me.
If Using Ground Control
When you find yourself in a situation where you have to reset your chains, set both sprockets vertical using "Actions->Set Chain Lengths - Automatic" but **DO NOT** press "Set Zero" .. instead press "Quit". You'll get a message about quitting calibration early and then be brought back to the Actions menu. Now, re-place the marked links of each chain back to the top teeth of the sprockets. If all is well, the sled will be in the same position as it was had you actually gone through the adjust chain process. Lastly, press "Actions->Advanced->Set Chain Lengths - Manual". This will send a code to the controller to tell it that the chains have been extended. Voila.. chains reset.. the easy way.
If Using WebControl
Set both sprockets vertical using "Actions->Set Sprockets Vertical" (It's in the Calibration/Setup group). Once both sprockets are set vertical, re-place the marked links of each chain back on the top teeth of the sprockets. If all is well, the sled will be in the same position as it was had you actually gone through the adjust chain process. Press "Manually Set Chains At XXXX mm" (XXXX will be whatever Extend Chain Distance is in your settings). Voila, chains reset.. the easy way.