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  1. #1
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    Benching into wide & flat area

    Have a look at the photo below. We've routed a few dozen feet of trail along an old footpath, or maybe its the remnant of an old logging trail. The hillside comes down from the photo's left, levels out for 4-6 feet and drops away again.

    Benching into wide & flat area-bench03.jpg

    I benched the bright spot in the trail that you see close to the bike. What I found is that I actually had to scrape about twice the width of the trail in order to get the downslope that I wanted.

    In the area closer to you in the photo I'm afraid I'll need to work all the way out to that log, because just past the log is where the ground begins to slope downward again in a meaningful way.

    It is tempting to leave that stretch of trail alone and not even bother to bench it. Is that a reasonable thing to do?

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    Dunno. But looking at that photo... it looks fine to me. Mostly level tread already, and dry as a bone on the day you took that picture. I would ride it as is until you see a specific problem (poor drainage, deteriorating soil conditions, etc). You could always just make a little drainage trench that leads around the log, too (to avoid moving it and benching the entire area).

    But there looks to be a subtle left turn in the foreground. I would advise to avoid out-sloping turns - they are no fun to ride and only deteriorate further.

    I just posted on your other thread about doing full benches and not half-assing it. If this is an example of area that you were unsure about, I rescind my comment (somewhat). Looks ride-able to me!

    P.S. what area of the country are you building in? ( I wish this forum showed peoples locations next to their posts, in the user stats area. )

  3. #3
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    Thank you Deezler. What you see in the photo is part of that few dozen feet of existing treadway that I mentioned. Not sure why it was there. It was something that had been walked-in over the years, or maybe some ATVers did something there once. Hard to say.

    I test-rode the stretch yesterday. The few feet that I benched was a humpy spot that annoyed me. So maybe I'll leave the rest of that treadway alone. It side-slopes more than I'd like, but I guess it's not terribly bothersome.

    I'll take another look at that turn you speak of. Looking at my other photos, I believe the route turns slightly uphillish at that point. I really need to get on the ground and look again, and not trust my memory.

    Area of country: I am in Munising, Michigan. Very sandy soil. Heck, it's probably all sand for 100-200 feet down, if not more. Our hills are all sand with a thin layer of vegetation holding them together.

  4. #4
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    If you are in well drained soil then I doubt you'll have any trouble with the section. I'd leave it for now and keep an eye on it.

  5. #5
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    Quote Originally Posted by JonathanGennick View Post
    Have a look at the photo below. We've routed a few dozen feet of trail along an old footpath, or maybe its the remnant of an old logging trail. The hillside comes down from the photo's left, levels out for 4-6 feet and drops away again.

    I benched the bright spot in the trail that you see close to the bike. What I found is that I actually had to scrape about twice the width of the trail in order to get the downslope that I wanted.

    In the area closer to you in the photo I'm afraid I'll need to work all the way out to that log, because just past the log is where the ground begins to slope downward again in a meaningful way.

    It is tempting to leave that stretch of trail alone and not even bother to bench it. Is that a reasonable thing to do?
    Does water run down the length of the trail? The best time to have checked this was earlier in the spring.

    If the answer is "no", adjusting the outslope of the tread isn't necessary. If the answer is "I don't know", then you might want to make a knick, or a divert, or a rolling grade dip halfway down the inclined part of the trail and check how the water is flowing next spring.

    Walt

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    Quote Originally Posted by Walt Dizzy View Post
    Does water run down the length of the trail? The best time to have checked this was earlier in the spring.
    Not in that spot, no. I don't believe so. The trail is close to level in that stretch, in the direction of travel.

    I bought an inclinometer today and measured the outslope. The tread where I benched slopes 2 1/2 to 3 degrees outward at one end and actually hits 5 degrees at the other. IMBA calls for 5 degrees, right? So I think I am ok, at least in that one eight-foot segment.

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    You should clear the leave from the downhill side and rake it every fall. If water builds up when it's wet you can dig a shallow ditch along the downhill side.
    There's a big difference between ripping and skidding. Those who skid don't know how to ride.

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    Munising - awesome! Love that area. I'll have to bring a bike to ride your trail when I come camping at Pictured Rocks this summer (hopefully).

    I am starting to punch in some trail segments on my own land down here in Southeast MI. And while our conditions vary a bit more down here, I am in some pretty sandy soil myself. I was still surprised to see that water never even threatens to puddle on areas of the trail I have yet to fully bench out. (that should theoretically trap water). I bet you'll be fine up there - just make it pleasant to ride (and sustainably so!) and the drainage should mostly take care of itself.

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    Quote Originally Posted by deezler View Post
    Munising - awesome! Love that area. I'll have to bring a bike to ride your trail when I come camping at Pictured Rocks this summer (hopefully).
    LOL! Then you can tell us all where we went wrong.

    Hopefully by the time you get up here we'll have enough to make bringing the bike worth the effort.

    ...I am in some pretty sandy soil myself. I was still surprised to see that water never even threatens to puddle on areas of the trail I have yet to fully bench out. (that should theoretically trap water).
    I'm not too worried about mud puddles. What I do worry about is the ease with which the sand erodes if we don't shape and route the tread properly. There is a fall-line segment of ATV trail that runs adjacent to where we are building. It's an eroded out mess that's easily four feet deep or more in some spots, with easily ankle deep loose sand and deep ruts, and all that sand washes down to where we currently park our cars when doing trail work. It is a glaringly obvious example of what not to do that I refer to whenever I bring new people out to help on the bike trail.

    On a rainy day I can take you out to various spots on the ATV trails and you can watch the erosion happen live, right in front of your eyes.

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    Good stuff.

    Is this a public trail, or is it on private land?

    How many miles of trail are you hoping to get installed this summer?

    Sorry to change topics, no problem if you don't feel like discussing these things in this thread.

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    Quote Originally Posted by JonathanGennick View Post
    IMBA calls for 5 degrees, right?
    IMBA calls for 5 percent. There is a big difference between degrees and percent. Make sure you use the correct scale.

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    ^ word. And actually, between 3-5%.

    3-5% outslope on a 24" wide trail tread = just one inch of drop across it. So, not much. You only need enough to let the water off.

    Suggest to read this sucker:
    http://www.wnymba.org/static/report/...BBT_Manual.pdf

  13. #13
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    leave it alone....

    and ride it and see what happens. That looks to be a trouble-free section in the trail from what I see. Continue on with trail building sir.
    Too wet to ride!

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    Quote Originally Posted by BonkedAgain View Post
    IMBA calls for 5 percent. There is a big difference between degrees and percent. Make sure you use the correct scale.
    Oh, one little teeny-weeny mistake.

    I will figure out the math and convert 5% grade into degrees.

    I am so ashamed. I will have my son whack me upside the head w/the IMBA guide tonight.

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    Quote Originally Posted by prooperator View Post
    and ride it and see what happens. That looks to be a trouble-free section in the trail from what I see. Continue on with trail building sir.
    I've been dragging a test bike along every time I go up to work. I am finding it very helpful to ride back and forth to see how a segment flows. Plus, we have so far had a good handful of high-school kids helping. I am trying to have two bikes available when they are out with us -- for morale purposes.

  16. #16
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    I LOVE the Munising area. I bet it's be a great place to build some trails (other than the crappy soil).

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