Wednesday, March 16, 2011

Pump Track Physics

My enginerd head has been trying get itself around pump tracks.

pump track backyard from Jason G on Vimeo.

As in, conservation of energy laws - you have to put energy in, somehow, to keep the bike rolling, and it's obviously not by way of the cranks. It's magical.

I'm not there yet, just getting started. Wonderful brain food for those 3 am can't-sleep sessions. With luck I'll eventually dispel the magicality and turn it into something logical and boring in my mind, but probably I'll just let it stay there and not kill the magic for everyone else. It looks so zen. But I don't know the first thing about it.

As for the kid, he's got some crazy shit burned into his psyche. Doesn't stand a chance of being "normal". Good for him.


John Speare said...

yes! obsess my friend. obsess. i hereby publicly pledge to spend many hours hauling, shoveling, packing, and swearing at dirt if you decide to put your giant double lot to proper use. i will even throw in on a bobcat rental, assuming I get to drive it a bit. and liza has a great dirt hauling truck. and we have the spokane mini on the way, which will prove all the naysayers wrong! f yeah!

Jason Gilman said...

That's pretty cool! I knew a pump track was a small banked track that people built in their backyards, but I hadn't realized the point was that they were ridden without pedaling before your post.

Anonymous said...

I suspect the soundtrack provides the additional momentum to maintain forward motion without pedalling.

I've watched lots of pumptrack on youtube, and all of them have soundtrack input.

Make sure to include a soundtrack in your design.

Unknown said...

push hard and extend your legs as you roll down a roller, then flex your legs and push down lightly as you roll up the next. there will be a net forward impulse.

mtbers on pump tracks work similarly to kids on swingsets, and like skateboarders on halfpipes.

Maddie said...

can i help? i already have a good outfit figured out: I have overalls that are very dirty already. Maddie.

Jonathan Eberly said...

Pretty cool. Never seen anything like this before.

Pat S said...

John, sounds like your're not all that crazy about the prospect of a pump track popping up in your hood. Sorry, man. I have rights.

Maddie, you can definitely help. Your outfit sounds all kinds of cool and just right for the job. But you might have to throw the ball for Brandy while you're trying to work. Just so you know.

Andrew, the swingset analogy helps a ton. If I google 'pump track physics' I get zilch. But 'swingset physics' is another story. Pretty sure, as you say, that it's the same stuff going on.

Anon, rest assured. Soundtrack included.

Pat S said...

P.S. Andrew: What's your take on John's minivelo pump track assault?

Anonymous said...

I thought of another name for the Spokane Minivelo Pugsley Thing:

The spopuggalo.

Spopuggalos kind of do for pumptrack what juggalos do for hiphop.

Maybe ICP should be the soundtrack when John's pumping the track:

Fucking pump track, how does that work?

Anonymous said...


Unknown said...

i bet that the minivelo will work fine and be fun on a dirt track. it will probably feel a bit like a BMX bike: lightweight & nimble.

BUT, i bet that pedaling will be required, because unlike a BMX bike, the frame and saddle will be too dang tall to do all of the leg flexing/extending that pumping etc. require.

if i were in john's shoes, i would lower the saddle a bit and try that shiny salsa on a pump track.