Pushing through a BMX double
Dear Lee,
I bumped onto your site whilst desperately seeking info on a jumping technique that seems to be difficult to find on the web, at least if one doesn’t know the name of it. So in this video that is attached, Mike Day uses it as per text book example in the first jumps after the gate: he pumps the rear wheel mid-air.
http://www.youtube.com/watch?v=JsR_TjG_brU
My question then is, what does this achieve: I think that it is to scrub speed so as to allow for taking the lip of the jump with more speed and then scrub off some mid-air so as to not land too far. Am I correct in my thinking?
Yours,
Rauli
Hey Rauli,
Thanks for the interesting question.
This is a common technique among BMX racers. Some people call it “double pumping.” The modern term is “pushing through.”
Danny Caluag pushes through a double in the book Pro BMX Skills:
Click for bigger |
Why you do it
Because you are very skilled, and you are going fast, and you want to fly low and fast.
Riders push through jumps they know they will clear. This is an expert technique to carry maximum speed when you have absolute skill and confidence for the situation. There’s a real risk of clipping the frontside of the landing. Use this technique with caution!
How you do it
Jumping gets pretty complex, especially among the best riders, but basically:
• Suck up the jump. This means pushing down hard right before the lip then pulling up over the lip. This absorbs the lifting force of the lip and keeps you lower than if you’d pushing into the lip.
• In the air, push your bike away from you then pull it toward you.
• When you reach the top of the landing, the bike should be very close to you.
Study the above image. I sure learned a lot from watching Danny C ride!
Did I already tell you to be careful with this advanced technique? Learn all about jumping in the book Pro BMX Skills.
Benefits of pushing through
• You stay fluid and dynamic in the air. Anything is better than a dead sailor.
• You can feel out the landing in case you come up short.
• This up-and-down cycle is the same you’d use to pump or manual the same roller-double. If you’re going fast enough to manual, you manual. If you’e going fast enough to jump, you jump. IMPORTANT: You maintain the same up-down rhythmic engagement no matter what. This allows you to use whichever technique you need in the instant, without having to make major changes in your movement or timing. The best riders, like Danny C, mix and match techniques in a blur of power and smoothness. They ALWAYS maintain the same rhythmic engagement. This is a pretty advanced concept. Make sense?
• This is even more esoteric, but I love this stuff so: When you pull your bike toward you, you also pull your body toward your bike. This means your body is even lower when you land, and you get even more pump on the backside. Full racer radness!
• Most of all, pushing through a double is fun. Anything that keeps you loose and happy is going to help you ride better and faster. Do you know who taught me that? Danny C!
In contrast …
Racers rarely push through the biggest jumps. On this monster step-up at the Olympic Training Center in SoCal, Chris Powell pushes into the lip to get maximum boost then keeps his bike close until he’s ready to extend for landing. This approach is more conservative — but pretty sweet.
 Click for bigger |
Have fun out there,
Lee
Know more. Have more fun!
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Thanks for your engagement, Lee! It seems I would agree with the majority of what you’re saying, as regards the purpose of pushing through (great to have the term for than now!)and to a large extent to how to do it.
However, I would point out that in the ‘benefits’ section I’m not so sure that the concept of the push through makes sense. I would contend that the problem is somewhat different: it would seem to me that you use a push through when you are going too fast to jump (to jump a neutral jump)and as such it is a ‘reversed’ manual; to push through, it would seem to me, is to pump a jump, same as you pump a ‘roller-double’. As such, pushing through, could not be likened to a manual, but is the equivalent of a ‘jet-hop’ (another term I learned from your site!) However, it seems that you would push through to slow down your forward movement, just as is the function of pumping: you pump if you don’t have enough speed to manual. Thus, to push through would be to convert a jump into a jet-hop, which could then be called a pump-jump, since it slows a jump down to the ‘up-and-down cycle’ of a manual. In the videolink above from the olympic TT we see how Donny Robinson just kind of jumps those first jumps neutrally and overjumps them, resulting in excess airtime and landings which do not make use of the shape of the landing.
Another really cool observation that you put forward is that when airborne you pull your bike toward, you also compress yourself at the same time! That’s a worthy point to notice, dude. However, again, (sorry, not trying to be a pain in the back or a wise-crack, but as you say, this stuff is just super interesting, and I’m fascinated, too) I have a somewhat different idea regarding the result of this phenomenon: for, when you land compressed, It seems to me that this is precisely the opposite of getting a pump because you will be effected by the downforce of your body and bike landing and this force will keep you compressed for that little second, rendering you unable to manouvre or get on the pedals. This is seen so clearly in Day’s case on the video link above: if someone were to land in sync with Day, but more extended, they could then pull on the bars to pump, or get on the pedals sooner than Day, who’s affected by downforce.
I’m not quite sure I got the idea of always maintaining ‘the same rhythmic engagement’, so if you have time at some point, could you maybe drop a couple of more lines on that. (Ah, maybe I should just buy the book, just being a cheap student:)
@Rauli
Once you leave the ground, you cannot “scrub speed” (with the exception of manipulating air resistance which I believe should be ignored in this conversation). You are in the air, with nothing to bear against. All body movement in the air is with respect to your center of gravity, which is flying in a nearly perfect ballistic arc. The push through is therefore not a jet hop, which is distinguished by contact between the rear wheel and the ground, resulting in an up force (the ‘hop’ part). I don’t want to put words in Lee’s mouth, but the push through is simply an air/jump, with the freely flying body mimicking the motions of a pump or a jet hop, **but not touching anything**, therefore just like a normal air/jump landing spot can be altered (you put your landing gear down earlier or later), landing body position can be altered (compressed or stretched out), but none of the stuff (like speed) that you are talking about can be. You can’t pump air. Good luck!
Lee, I know this as an expression pronounced ’emming’ – named after the letter ‘M’ which is the letter traced by the back wheel – up, down, up, down.
I would like to chime in that riding with measured aggression is always going to make you faster than riding without it. If I dead sailor a jump I don’t feel as fast MENTALLY as when I pump the heck out of it. Unleash the fury and you will release the speed.
That’s why I used to race DH with my ‘Palmer Face’ as per the cover of the video ‘Chainsmoke’.
Thanks Matt and Chris.
I’ve been working on my Weir Face, hence the beard.
I haven’t reached Kung Fu levels to do a controlled and conscious double pump. But I’d say that I can understand how push through can really lower and shorten the flight. If you can have two days on A-Line kind if trail to test such techniques you will be amazed how short you can land in contrast to launching the lip. At some speeds normal squashing doesn’t help anymore even if you stand on your toes before the lip, time it right and get the rear tyre into your crouch – no matter what you do too much speed for the size of the jump and squashing will actualy turn you into a dead sailor, that’s why you need to kind of jump before the…jump. By doing this you are directing the vector of your CG before the lip does it at the same time squashing it a bit, hence minimizing its ability to launch you upwards. However I think that Lee is perfectly right with saying to be careful as Timing is everything at such speeds and I can only imagine that push through done too early makes an ultimate dead sailor going through the front door 😀
Ah and there is the third way to shorten tha jump and that is one of the most effectful, sick rad things you can do on a mountain bike and that is: doing a Scrub 🙂 you get lower by leaning the bike and you direct the upward force of the lip sideways. Someone please teach me that 😀