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  1. #1
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    Pump Track Plans

    Hey all,

    I am once again thinking about building a pump track in my back yard. I was all ready to get going on one a couple years ago, but other responsibilities got in the way. Hopefully I'll move forward with it this time. I want to build a fairly basic track that is fun but will also let me push it once I get better. I am thinking I could build forms out of plywood for the rollers - similar to a jump ramp except without the top surface - and fill them with dirt. This will provide some support to hold the dirt in place and also give me a guide to make the perfect sine curve. I'll use rocks to mark just outside of the perimeter of the berms since I have alot of them around the yard. I'm thinking they will offer some support and maybe reduce the amount of dirt I will need. Other than confirming that those are sound ideas, I have a couple of other questions I would like some input on.

    First, the soil I have access to is a kind of crumbly/loamy/dusty soil. Anyone know if there is a way to get it to pack together well? I could try to find some more clay-like soil, but it would probably be expensive.

    Second, as far as designs go, I have three different concepts and I have attached a picture showing all three. The most basic is two straights with two 180 degree turns. The rollers go from 1'3" for the end ones, 1'6" for the second in from each end and 1'9" for the middle. The radius of the outside edge of the turns is 14'. The next track is the same basic design except with four 12' radius 90 degree turns. I also added a straight section with three 1' rollers between the turns. Finally, the triangle design has a 10' radius 90 degree turn and then two ~135 degree turns, one 12' radius and one 14' radius. One straight section is the same pattern of increasing sized rollers to the middle as described above. The other straights are 1' rollers and 1'3" rollers. In all the designs I would not build the center transfer sections initially. I also could make one of the straights in the designs a larger table top or two rather than rollers. I think all three designs would call for about 50 yards of dirt. Also, our entire yard is fairly flat so elevation change isn't really an issue.

    So, any input on the track designs or build concepts. I know alot of you would say make it more dirt jump and less pump track, but I am getting older and crashing hurts and often causes longer term damage to my body so I am more interested right now with getting excersize and increasing my skills versus getting big air. If/when I add the center sections I could shift some things around and add some more jump features.

    Thanks for any comments.

    Matt
    Attached Thumbnails Attached Thumbnails Pump Track Plans-pump-tracks.jpg  

    Last edited by snmhanson; 09-03-2012 at 10:06 PM.
    2008 Titus El Guapo
    2011 Transition Bank
    Giant Yukon HT w/ skinny tires (for family rides)

  2. #2
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    Buy Lee Likes Bikes e book for a start. You'll have guidelines for dimensions and the core rules of start outside first.

    For a small space I'd indeed start with the outside first. When you know how that rolls you'll know where and how to move in a different direction.

  3. #3
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    Thanks for the reply. I actually have Lees book and the triangular track is inspired by one of one of the sample plans in his book. I used his recommendation of 10-1 spacing of the rollers in each of my plans, and when I get around to building, I will follow his advice. I do value the practical advice offered here on MTBR as well though, so I figured I would see if anyone has any additional input to offer on the track layout or construction tricks. For example, I am looking at a range of berms from two 180 degree berms to four 90 degree berms, and then of course the triangle with one 90 degree and two 135 degree berms. I'm not sure which would be easier and more fun to ride while still offering up a challenge as my skills improve. I know it's just dirt and I can change it over time, but I would rather start off with a versitile design than have to keep making changes.

    I'll certainly start with the outside loop and then go from there. Not even sure if I'll build the interior transfers or not, but the option would be there. Depending on how quickly I can get started, this may also turn into a spring project, though I can cut the wood forms and get those ready of our cold and rainy Washington winter. Hopefully though I will make some progress this fall.

    Thanks again,

    Matt
    2008 Titus El Guapo
    2011 Transition Bank
    Giant Yukon HT w/ skinny tires (for family rides)

  4. #4
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    Profile view of the track will give you a better idea of the flow. You should have the elevation and spacing of each roller/feature already on paper. There're specific ratios that make a track fun to ride. Experience make a difference at that point.

    You didn't account for landscaping on your plan. All features should have at least a 1:1 ratio on the backside. A 1.2m tall berm will need some space behind it. This can cause major drainage surprises if you don't consider it from the start.

    Also, most berms in Lee eBook are freaking tight. We average 4m radius on most of our tracks. Depending on the skills of the rider, we go down to 2.5m to 3.0m but never under that. Longer berm will require massive speed or a feature midway to maintain momentum.

    This will also allow you to calculate the volume of material needed. You should also account for a 1.3 to 1.8 ratio for compaction depending on the type of material used and the base of the track.

    I can send you some examples of track we built. Email me for info.
    A trailbuilder from the north

  5. #5
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    nice, i'm in the same boat. overall space is around 30'x50' that i will use.

    thread is here
    building a pump track...
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  6. #6
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    Thanks for the additional feedback. I am attaching a profile view of the rollers. As the image shows, there is roughly 10 times the distance between rollers compared to the height of the rollers. Also, they are nice gradual curves that should be easy to navigate, but with just enough steepness to generate some power. Let me know if they don't look right. I'll think about the radius of the berms. What radius should I consider to make a fun and rideable track? Sounds like 10-14' would be about right. I've got plenty of space to work with in terms of layout and landscaping and neighbors are not an issue. My biggest issues are finding the spare time and getting my hands on some decent soil, and then of course the skill to build it correctly. And I still can't decide whether more turns of less turns would make a more enjoyable track. I don't think I'd build the track with two 180s, but either of the other two might be fun.

    Thanks,

    Matt
    Attached Thumbnails Attached Thumbnails Pump Track Plans-rollers.jpg  

    2008 Titus El Guapo
    2011 Transition Bank
    Giant Yukon HT w/ skinny tires (for family rides)

  7. #7
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    prepare yourself for a LOT of work. even after it is built, it is a LOT of work.






    but damn is it fun!


    The fastberm is 14' radius and about 2.5" tall now (was 3'+ a year ago). the 90 berms are 10' i think. (I use a 20" bike very rarely, most of the time is it fat bike or 26" dirtjump so my berms need to be longer)
    all rollers were built 1'x10' (very fast and fun)
    used flags and spray paint to make sure everything went where it was planned. (measure twice, wheelbarrow once. clay is heavy)
    ~50' of french drains to keep water levels in check after heavy rains
    tarps for the entire track help keep the weather off and plants from growing

    if you were local...

  8. #8
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    OK, here is my latest rendition of the track. I decided that 12' radius berms (radius to the lip of the berm) might be a good balance between power and controlability. The actual radius of the berms where the tires run will probably be closer to 10' once all is said and done. Also, the two rollers in the middle of the diagonal sections create kind of a pumpable step-up/table top feature. They only extends 1/2 way across the width of the track so they would be optional. Any advise on this new plan? Berm radius seem ok? Roller height and spacing? Anything that looks like it might not work? Looking at things right now it looks like the spacing of the rollers on the sides might be a bit tight. Maybe three rollers instead of four? Or make them shorter in height? I would greatly appreciate any input before I start building.

    Thanks,

    Matt
    Attached Thumbnails Attached Thumbnails Pump Track Plans-pump-track.jpg  

    2008 Titus El Guapo
    2011 Transition Bank
    Giant Yukon HT w/ skinny tires (for family rides)

  9. #9
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    For a small track, figure 8 & heart shapes seems to offer a good balance of turn/roller. Offering the option to switch direction is a big plus also. Always turning the same way become annoying at some point (and most track are usually more fun a way than the other).
    A trailbuilder from the north

  10. #10
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    Do you have dirt on site? You will be using a lot of dirt...

    the 18"x9' rollers might be a little rough. what about a stepup or another bmx track looking feature to throw the spacing back into alignment.

    6' wide is pretty big. mine is under 3'

    The odd berm out i would tighten up the radius to allow you to pop out of the corner with more speed. and just to mix things up.

  11. #11
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    Quote Originally Posted by dl1030 View Post
    Do you have dirt on site? You will be using a lot of dirt...

    the 18"x9' rollers might be a little rough. what about a stepup or another bmx track looking feature to throw the spacing back into alignment.

    6' wide is pretty big. mine is under 3'

    The odd berm out i would tighten up the radius to allow you to pop out of the corner with more speed. and just to mix things up.
    We have five acres and alot of dirt, I just don't know how good it would work for the track as it's a fairly crumbly loam without much clay. I might start with the dirt we have here on site and if it doesn't work well scrape a few inches off and bring in something better for the top. We also have a ton of large rocks/boulders on our property so I will use those as fill. I have read the warnings about using rocks as fill, but these are pretty big boulders that would be easy to seperate from the dirt if I had to move a roller or berm. Also, I have a tractor and bucket which makes the process much easier than doing it all by hand.

    I will look at alternatives to the 18"x9' rollers. I want to be a bit careful about putting in features that will kill your speed so I may leave them as rollers and just stretch the lanes out a bit. I can always add fun features down the road once I get a fast and flowy track. I will also look at tightening the fifth berm up a bit. Once again though, I want to make sure it is going to be a speed killer. On a track I ride quite a bit there are two 12' berms and one 9' berm. You always see braking ruts at the entrance to the 9' berm. As a matter of fact, I generally have to brake coming into that one to keep from getting thrown off the track and into the tree at the exit of the berm. However, when I do rail it I seem to come out going faster than when I entered.


    Quote Originally Posted by HypNoTic View Post
    For a small track, figure 8 & heart shapes seems to offer a good balance of turn/roller. Offering the option to switch direction is a big plus also. Always turning the same way become annoying at some point (and most track are usually more fun a way than the other).
    Thanks for the feedback. The track has perfect symmetry so that it should be virtually as easy to ride one way as the other. I am sure there will be some differences in each direction, but as much as possible I want to make it rideable in both directions. I may add some additional features later that might work better in one specific direction, but I want to start with somethign versitile.

    One last plan just so you can see where I am hoping to go with this. I took the original design and kept the four corner berms at 12' and made the rest of the berms 10'. I obviously added a bunch of lanes and made everything come together at a middle feature which could be rolled, railed, or used to transfer to a different lane. A track like this is my ultimate goal, but I need to start somewhere. The plan a few posts down would allow me to eventually end up with this.
    Attached Thumbnails Attached Thumbnails Pump Track Plans-pump-track-vision.jpg  

    2008 Titus El Guapo
    2011 Transition Bank
    Giant Yukon HT w/ skinny tires (for family rides)

  12. #12
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    I'm planning on building a pump track soon so thanks for all the good info here. I'll post up once I have plans etc

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