Learn the rear wheel lift: wedge between bars and pedals, press the soles, hips up. 5 steps with milestones, typical mistakes and safety notes.
The honest answer first: with flat pedals you lift the rear wheel by "wedging" yourself between bars and pedals, pressing the soles of your feet firmly onto the pedals and bringing your hips up. You do not need the front brake for this. That is how BASPO, the Swiss Federal Office of Sport, describes it [1].
With clipless pedals, by contrast, it is enough to "hop" slightly with your legs and pull them up [1]. The difference matters because with flats you work only through pressure of the soles. That is why DIMB recommends flat pedals for learning: the tension in the bike should be learned without mechanical help [2].
What do you need it for? Lifting front and rear wheel in combination is, according to BASPO, a direct preparatory exercise for pumping (unweighting and weighting) and the bunny hop [3]. On the trail it helps with obstacles that would otherwise stop the rear wheel, and in tight passages.
How hard is it? You learn the movement in an afternoon. It becomes clean and controlled after a few weeks (experience-based), because pressure, tension and timing must fit together.
It is not the pull on the bars that lifts the rear wheel, but the pressure of your feet.
You roll slowly in the base position, cranks level, fingers on the brakes [1].
Milestone: 30 seconds of standing roll without correcting your position (practice).
Shift your upper body forward and down. The centre of mass moves forward, where the front wheel stays [1], [3].
Milestone: on the side video your upper body is lower than when rolling in, the arms are not locked straight.
Wedge yourself between bars and pedals. That means: body tension, toes down, soles pressed onto the pedals [1].
Milestone: you feel pressure in the soles without the bike swaying.
From the pressure you bring the hips up and pass the momentum onto the pedals. The soles stay on the pedals and the rear wheel lifts [1].
Milestone: you lift the rear wheel a few centimetres, five times in a row, without the front wheel deviating.
Land with your legs absorbing [1]. Shortly after landing you are back in the base position.
Milestone: five clean repetitions where the rear wheel lands without a thud.
If the rear wheel is lifted too high, you risk flipping forward (practice). Over the bars was the sequence in 55.2 percent of 534 analysed mountain bike crashes [6], mostly through sudden deceleration. So do not touch the front brake, and keep the height low.
The most common injury sites in mountain biking are the head and upper extremity [7]. In a meta-analysis across cyclists, a helmet cut serious head injuries by about 60 percent [8], a figure for cycling in general. Practise on soft ground with run-out, without traffic and never near edges. This guide explains and motivates, it does not replace supervised training.
Separate pull and pressure in your head: the hands hold, the feet press. In the rear wheel lift the weight acts through the feet, not the arm on the bars. That also explains why it works more cleanly with flats: you feel at once whether the pressure is right. DIMB considers flats better for learning for exactly this reason, because the tension in the bike arises without mechanical help [2].
One more note on shoes: flat-pedal technique lives from grip between sole and pedal. Firm, flat soles and grippy pins make the pressure of the soles predictable (practice). If you keep slipping off, it is often not your technique but the shoe or worn pins.
Base position, upper body forward and down, wedge between bars and pedals, toes down, press soles onto the pedals, hips up, absorb with your legs. The front brake stays unused [1].
Yes, and more easily: hop slightly with your legs and pull them up [1].
For obstacles that would stop the rear wheel, and as a preparatory exercise for pumping and the bunny hop [3].
Your upper body stays too upright or too far back. Bring your upper body forward and down so that the centre of mass sits over the front wheel [1].
BASPO names no height. A few centimetres are enough for practice (practice). The higher the rear wheel goes, the greater the risk of tipping forward, and the higher the speed, the harder the technique becomes [3].
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