Biketrials pedal hopThe Static Hop: one burst to go
The static hop helps when there is no room for a run-up, with the front wheel already up on some corner. Very useful in real trials riding on sharp rocks or weird shapes. It is a good preparation for launching a pedal hop from an edge where you can only transit quickly on the rear.

Start already in balance with the front wheel up onto some edge or kerb
1° From there, flex down on the bike as much as you can, like a spring before impulsion. Keep the brakes full-on all the time. 2° Extend to the maximum in one hop, pushing on the legs to jump but also with the arms to boost your impulsion on the bars (the front wheel is static). 3° To follow up with the impulsion, you should pull on the bars to lift the bike forward, while lifting up the knees to let the bike go up.
Then, try to stay in balance on the rear wheel.
See the move in a video and also in slow-motion

video
Excellent to reach some edges

More tips?
The best places to practice are stairways, or small wood logs. To boost the impulsion, really try to bounce back from your flexion by using the spring of both your legs and arms (and low pressure bouncing tires). When you get the right move, you can land directly on the rear wheel one step higher. In difficult situations, you can even try to combine it with a pedal kick at the very end of the impulsion, to give it a boost.

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Rolling on the front
If the obstacle is wide enough for both wheels, just roll over by pulling on the bars after the extension, and then pushing the bike in front of you. That is smoother than pulling up the whole bike in the air (for nothing) and it is less physical. But if you feel like it, land directly on the rear wheel, with the front wheel in the air. video
Climbing on a beam

At a Pro level: pushing the move further
Experienced riders are able to run this technique with amazing precision, on sharp edges, slanted corners and other slippery stuff where any miscalculation could result in a nasty crash. Concentration is decisive, especially when the ground is far below you.
video
Ben Savage hops after rolling-over
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Cesar Cañas preparing a gap jump
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Chris Akrigg nailing a fork lift truck