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Loser
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Discussion Starter · #1 ·
I got my wife hooked on the idea of a pump track in our back yard. She ran with it and the next thing I know there's a 30 yard pile of dirt in my yard! All good! The dirt is super for pump track build, its got a lot of clay in it, very dense and should pack down very well.

I have a 50' x 40' area in the back yard that is relatively flat, there are some trees in the middle of it, but I will work around them. I drew out the below on Powerpoint, not the best for doing this thing - but I'd like some feedback on this before I start clearing and moving dirt. I have more room to the right to expand, but I think this is somewhat manageable. The greyed out area has a large rock and 3 large trees in it, probably off limits to some degree.

Anywhere there is an arc would be a berm, the straight lines would have bumps on them, I still need to figure out the spacing and height of the bumps. From what I've read its best to get the berms in first. The large-ish turn in the middle on the left would allow you to reverse direction.

Any feedback appreciated. I'll update this thread as I progress.
John

 

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Turns look a bit tight.

I would suggest trying to open up your turns to around a ten foot radius at the tightest. Maybe try just a simple oval style track at first on the left side of the trees and such. Dial that track in and learn the fine art of sculpting and flow. Simply dialing a 50x20 track will be enough to keep you busy for the fall and winter. Then, as your skills increase add little bits at a time. If patience isn't your things hire a pro.

Ben
 

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Loser
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Discussion Starter · #5 ·
That's probably good advice, unfortunately I have 30 yards of dirt on my yard that I have to move sooner than later.

But maybe I will move all the dirt, but only do the actual sculpting of the berms a few at a time... I'll have to think about that.
 

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giddy up
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I built a track this summer (and I am still and will always be working on it) and the one thing I would say is don't worry about the pile of dirt that is sitting in the front. Move as much as you can but the priority should be to dial in 1 or 2 sections in first like the previous poster mentioned. Just cover whatever is still in a pile out front with a tarp, it will be fine. Don't rush it and buy a can of orange spray paint and measure measure measure. Building berms first is a good idea and per Lee's book, get a string and make sure and I mean make sure that the "riding line" is where half way up the berm is going to be. If it isn't, move backwards of forwards, you'll either do it now or later I can guarantee it. This got me and I just literally reshaped one of my berms today because it just wasn't working the way I thought it should be.

Rollers should be sine waves as Lee's book states. I wouldn't say "no flat spots" but a good measure is to take the bike that you will be riding and it should just barely fit in between the transitions of the rollers. As soon as your rear wheel comes down off of a roller the front wheel should be touching the next roller. This should be the maximum distance. You can make them closer which adds to the excitement and opportunities for manuals and jumps but any further and you'll really working for momentum.

Good and luck and as Lee himself says, when you have 90% of the track complete, 90% of the work remains.
 

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giddy up
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203 Pump Track

Jisch,

Here is a link to a short video of the track I built. It's changed some but mainly tweaks and modifications. I spend everyday buttering it up and today was a good day. I've got it so close to perfect (perfect meaning absolutely no pedaling and high speed/minimal braking) with a jump thrown in. So damn fun.


Cheers
 

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Jisch,
No technical knowledge to add, but I ridden a few and unusual features def make some better than others.
Here is a video of one of my favorite tracks (more of a hybrid pump/bmx track)

http://pics.bikerag.com/showphoto.php?photo=7555

And a list of my favorite features-
1) bumps instead of berms- learn to jump and turn rather than always carving
2) elevated doubles /^^\ - to jump or manual
3) open s features- hard to see, but at the beginning of the video it a three dimensional open "s" feature. You throw the bike into a very open berm that ends in a j shape and kicks you into one on the opposite side
4) Pyramids into berms- Jump over the front, down to a side and carry serious g's into a berm. Would work right at the southwest edge of that gray block

Not sure if that will help you at all, but good luck!
 

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Discussion Starter · #10 ·
Thanks - cool ideas. I am definitely looking to incorporate jumps/doubles in this as well - that's quite an area in the video - wish I had that much area to work with!

John

BTW - I have changed the design on paper after walking the property:
 

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giddy up
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I just finally got an "elevated double" to work and you jump it and land into the berm and come out faallyyin. I like the layout you have. Looks you you'll have so many options. Post photos when the diggin starts.
 

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Discussion Starter · #12 ·
Here are some "before" pictures. I guess the real before pictures would have been taken a few weeks ago, but a picture of just woods wouldn't be worth much.

My pile 'o dirt - its much bigger than it looks, I thought by standing in front of it I would give some perspective, it doesn't. The piles are taller than I am. This is two full triaxles full of dirt - the driver of the truck said each one carries 14-15 yards of dirt - so 30 yards. According to the calculations in Lee's book this will be just about enough to do the track:




I am still concerned about having enough dirt. Where I live we have ZERO topsoil, its all rocks so taking advantage of what I have I am making retaining walls of sorts. My thought is that this will reduce the amount of dirt I need for the berms. I am only doing these walls on the outside berms, the inside berms will be all dirt so I can reshape them at will. I am building the walls 2' out from where the riding line is going to be (theoretically).




I marked the center of the arc for each berm and raked out a 2-3' wide path where the berms will be. I also raked out the entire track as per the above drawing (with the exception of the crossover, interior path.



I've got probably another hour or three of moving rocks to make the walls a bit higher then its earth moving time. I can rent a bobcat and someone to run it for $200 + a 30 pack. I'll probably start moving by hand this week and see how it goes.

John
 

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Discussion Starter · #13 ·
Its been extremely dry since I got the dirt and I've been moving it into the berms. I've got 3 of four berms started - I've done some basic shaping, but mostly just piling dirt. As I noted this dirt has a VERY high clay content. It rained all day yesterday and we got about an inch overall. I went out last night and put a foot on one of the berms and my foot sunk an inch into pure muck. I am wondering if this is always going to be the case after rain or if it will firm up more after it's been tamped down?

I'll post up more pics shortly..

John
 

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Get a peice of 2x10 about 10" long. Screm it to a 4' 2x4 and use that as a tamper or buy one. Pack a decent berm and before your done for the day tamp it. Keep the dirt well packed as you go and the rain won't bother it but instead it will make them sweet.
I'm building one in my backyard now. I should have 4 loads of dirt here wed. evening. I have 4 berms started and there is going to be multiple lines with many options. All flow (hopefully).
Good luck on your's it's looking like your going to have a nice track.
 

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Discussion Starter · #16 ·
Thanks - yeah I should have tamped them before the rain. I have to wait for them to dry out now... Really glad to hear that it will shed rain when tamped. I have a tamper.

John
 

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Discussion Starter · #19 ·
Nice tip on the burlap - I will try it.

BTW - nice pump track in the first video there... I can only dream that mine will look like that, but that's what I'm aiming for.

John
 

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Discussion Starter · #20 ·
I will take some pics if the sun every comes out! I went out at lunch and did a few loads of dirt. As I said this stuff has a VERY high clay content. Its very heavy and I couldn't move nearly as much volume as when it was dry. I could practically use a trowel to form it once I got it loaded into the berms.

John
 
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