Know the type of group you're joining, and whether it's a good fit for you. If you struggle to maintain 20mph on flat ground, and have little-to-zero pack riding experience, joining the local racer-boy group ride is not going to go well, and could be dangerous for everyone. If your intent is to hammer at race pace, and attack the group, this is not going to be welcomed behavior for a slower-paced, no-drop, casual/coffee ride.
Also...Protect your front wheel, hold your line, and brake smoothly.
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