Thankfully, we have "DOCUMENTED VIDEO EVIDENCE" of snake encounters on bike paths. Since the original question is not specific about the type of bike, trail, rider, speed, or snake involved, answerers had to guess.
Of course, with all these variables, the answer has to be, "it depends."
GENERAL BROAD ANSWERS FOR ALL SITUATIONS:
1) Avoid running over any part of the snake, if at all possible.
2) Do the best you can under the circumstances to give the snake a wide berth, whether by slowing down, stopping and waiting, or stopping and walking your bike off the path and around the snake. Pretty much all snakes you encounter on a trail will avoid you and slither away if they are given the chance. The only snakes that will attack you would be doing so to defend themselves. (Australia may be a special case) Bonus points: stop well before the snake but close enough it senses you, and wait there until it slithers off the path, to alert other cyclists, and help the snake avoid being run over by the next biker down the path.
3) Biker safety first! Whatever else you do, be safe and try not to make such sudden, panic maneuvers that you crash and the snake then becomes the least of your worries. The guy on "Large snake on MTB trail, very limited reaction time" does a great job. In another video, a guy brakes rapidly with his front brake and flies over his handlebars. At least while airborne he was out of reach of the rattlesnake! However, I do NOT recommend this airborne technique...
SPECIFICS FOR DIFFERENT TYPES OF SNAKES
RECOMMENDATIONS FOR SMALLER SNAKE, 1.5-3 FEET LONG, TYPICALLY NON-VENOMOUS
- Do everything you SAFELY can to avoid running over ANY part of the snake. A bike running over this snake is likely to kill or seriously injure it.
SMALL SNAKE VIDEOS:
- Small snake 1 injured/died from being run over by bike
- Small snake 2 injured/died from being run over by bike
RECOMMENDATIONS FOR LARGER SNAKE, POTENTIALLY VENOMOUS
In some videos, you will notice the startling speed at which these snakes can move and potentially strike.
Given a rapid and surprise encounter with a large snake, assume it is venomous. Be safe first and analyze species later.
Avoid running over ANY part of the snake, and give it as wide a berth as possible. * Stop if you safely can, back away from the snake, and give it time to slither off the trail.
Keep the bike between you and the snake if at all possible. See first large snake video below.
Don't stop and stay stationary within range of a potential snake strike (see "all bets are off" video below.
LARGE VENOMOUS SNAKE VIDEOS
- Large snake on MTB trail, very limited reaction time, see what the rider does!
- Larger snake at edge of MTB trail, rider does not see, watch what happens!
- This biker sees a rattlesnake and brakes abruptly, flying over the snake and over his front handlebars. The biker is out of range, but his bike gets slimed. I'm not sure what to say about this one; not a model, but everyone lived, nobody got badly injured. Simply an instructive example of what you might encounter.
- This is probably a typical scenario for an MTB rattlesnake encounter. The biker was going fast, had little warning, and took quick evasive action to the inside of the curve and barely missed the snake. Snake at about 1:40 on the video.
- Another rattlesnake. In this one, the biker didn't see the snake or notice it until editing the video later. Snake is at about 3:00 into the video. Sometimes it's best to be lucky so you don't have to worry about good.
- In this one, the rider sees the snake and manages to stop abruptly and safely and I expect the snake probably slithered off the trail.
OTHER, ALL BETS ARE OFF...
* Apparently things get very crazy in Australia with all the creepy-crawly venomous things on that continent. I guess the moral is if you stop on the trail, be aware of your surroundings. The video poster says it's a venomous snake; it's certainly aggressive to go after a stopped biker/bike on the trail! The real action starts about 45 seconds into the video.