Gaps and doubles demand above all a decision: prerequisites, speed, landing and cost of error. No recipes for big distances, but an honest roadmap.
The honest answer first: a gap or double is a jump across a gap between take-off and landing. Too short means a crash, in jargon "casing", the impact on the edge of the landing. That is why the most important ability here is not a technique, but the decision whether to jump. This guide gives you a roadmap for the decision, but no recipes for big distances. There is also no association or study description we have read for that.
What is documented: BASPO describes as a practice jump a small table without a gap a few metres long [1]. It names a controlled flight phase as the top aim and varying the approach speed as the most important element [2]. That is the logic of the gap: your speed decides where you land.
Why the caution? In the video analysis of 534 mountain bike crashes, poor jump landings preceded 64.4 percent of the over-the-bars crashes [3]. A fall during a jump doubled the odds of head impact (odds ratio 2.2) [4]. In bike parks, 20.8 percent of injuries were due to jump landings, fractures were the most common diagnosis (52 percent), and about a quarter of the injured were evacuated by helicopter (TRANSFER: bike park, not trail) [5].
How hard is it? It is the hardest skill of this series, not because of the movement but because of the cost of error.
In a gap it is not courage that decides, but the probability that you master it.
Ask yourself: can I land the small table 30 times in a row cleanly at the same speed? If not, the gap is not an issue (practice) [1].
Milestone: you can answer the question with "yes" and prove it on video.
Walk take-off, gap and landing on foot. How long is the gap relative to your speed? What lies behind the landing? Is there run-out? (practice).
Milestone: you describe the landing and run-out in your own words.
Speed is the decisive lever in the gap. BASPO names varying the approach speed the most important element in drops [2]. Set a run-in marker and first ride at the gap only without take-off to feel the speed (practice).
Milestone: you reach the marker in three approaches at the same speed.
Ask yourself: what happens if I am short? If the answer is "I case on the edge and crash", that is acceptable only if the landing is built for it. In a pilot study, experienced riders declined ramps when the product of perceived fall and injury probability averaged about 13 percent [7].
Milestone: you can name the probability and consequences in two sentences.
If prerequisites, speed and cost of error fit, you can ride it. If one of the three questions is open, the gap becomes a table today: you roll it or skip it. That is not defeat, that is the technique (practice).
Milestone: you made and justified the decision today.
Gaps and doubles are safety-critical. Severe injuries are more common in downhill, influenced by rider skill and trail design [9]. In mountain biking the head and upper extremity are the most common injury sites [10]. A helmet cut serious head injuries among cyclists by about 60 percent [11] (cycling in general).
We deliberately name no distances, take-off angles or speeds here: they depend on the jump and cannot be transferred by text. Practise only with experienced companions and with a coach, never alone and never under time pressure. This guide explains and motivates, it does not replace supervised training or a coach.
Turn the gap into a table first. If a gap is hard for you to judge, first ride a table with the same approach and the same take-off. Jump it until you reproduce the speed reliably. Only then comes the gap. BASPO names exactly this table as the ideal practice jump [1].
Both are jumps across a gap between take-off and landing, in scene jargon a gap or a double (two mounds). Too short means a crash onto the edge of the landing (practice).
When you land table jumps securely and at the same speed, control drops and can name the cost of error. No source we have read gives a fixed time or number (practice) [1].
That depends on the jump and on you, and we deliberately name no number. Start with the smallest version, preferably with a coach or experienced companions (practice).
No. Protectors are a fallback and do not replace control. A simulation study shows that test procedures for back protectors do not fully reflect the loads of real crashes [8].
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