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Discussion Starter · #1 ·
So on our local trail all our jumps are made of dirt and have a nice lip. I can easily pump these and get a great jump.

A buddy added a new jump made of wood and it has no lip (flat wood is the jump surface) and I find hard to get a good jump off it. Is the technique for flat (no lip) jumps different than one with a lip?
 

· killin clear creek
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It's pretty easy to add a lip to a wood jump depending on how it's built.

I'm in a dry area where it's hard to get dirt to pack, so I use wood. The only difference imo is that on something without a bit of pop (wood or dirt) you need to pop more yourself.
 

· Rider, Builder, Dreamer
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photos always help when asking such questions......maybe there is a lip, just not as steep of a lip as you have on some of the dirt jumps?

For some reason I feel more comfortable launching off a wooden lip. Dunno why. Plus that humming sound is pretty cool.
 

· trail addict
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Is it steep? Maybe make a dirt transition leading into it so it doesn't feel like you are "slamming into a wall" and losing momentum.

Or is it a shallow angle? Need a low, mellow landing.

Either way, speed is your friend. It will help make up for a little less pop.
 

· Roll on Spring Time!
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I have only just got the hang of building dirt takeoffs. I always ended up with not enough transition even when I knew it was a habit. Building wooden jumps is soo much easier to get right. Sounds like there is no curve/radius to the wooden jumps your build built. Building wooden jumps with a string line really helped me understand radius and that in turn helped improved my eye when building with dirt.
 

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Discussion Starter · #8 ·
I'll try and grab a picture but it' basically a ladder bridge type structure set up and at 15 degrees - about 6 ft long.

I just hit it more like a drop right now.
 

· Now with More Wood
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Jason B. said:
I'll try and grab a picture but it' basically a ladder bridge type structure set up and at 15 degrees - about 6 ft long.

I just hit it more like a drop right now.
So yeah, just to summarize for you what has been said here already be people:

You obviously don't get any pop off that lip because there isn't one, really. By the time you go airborne, you are simply traveling along in the direction of the plane you are on (which is a flat surfaced angled upwards). That generally means you will be arriving at the lip with little to no compression on the suspension/in your body, so you'll just end up floating out in to the air a bit disjointed unless you do something about it.
To do something about it, you can:
-add a lip to the jump, or build it in a radius as JP suggested (look up some of his posts for some nice pics of how to do this)
-bunnyhop/huck off the lip
-come with more speed (which also probably means adding a bit off dirt at the beginning of the ladder, so as to create a nice smooth transition onto it. This should help you build up a bit of compression in the suspension (which is what is giving you that nice solid feel/"great jump" on the dirt jumps you mention in your post). The more active you are on the bike at take-off, the better the jump will be, typically - flat wood ramps tend to just immobilize you and set you up nicely for some dead sailor action (or just riding off it like a drop, if there is no real gap to clear), so try to combat that by pumping the jump a little bit yourself. That is only possible to a degree though, no amount of pumping can replace the effect of a nice progressively rounded lip, especially not for the size of jump you are talking about (quite a short ramp that).

Here's a good video that illustrates this kind of jump, although this one is much bigger than the one you are describing (I have nothing to do with this video, just looked it up). You can see that people are using speed to clear the gap, but other than that, not much going on in terms of compression. Some of the guys going off this one even use a bit of drop technique (as you described yourself doing) to get into the right position in the air (given the lack of pop off the lip this ends up being a good way to regain some pedal pressure in the air). So depending on what you are trying to achieve with your jump, sounds like you could already be doing the "right" thing...


:thumbsup:
 

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I started a thread with pretty much the same title a couple of years ago, only to get flamed and accused by a few ******s on here (not naming names) for trolling.
Though the thread did have a few useful tips in it.
http://forums.mtbr.com/showthread.php?t=346043
I personally like wood jumps better when you have the wood and material to build them.
Where I live, we have about 1.5 feet of topsoil, then sand or limestone; not very conducive to digging up dirt. Also, I have access to scrap lumber whenever I need it; you also don't need a crew (or expensive equipment) in order to build a wood jump in a timely manner.
I could build, say, a 4 ft tall, 4ft wide, 10 foot long wooden jump in less than a workday by myself. I could not build a dirt ramp of that size by myself in two days, let alone one.
If I ever needed to relocate a wood jump, I could do it much easier and quicker than with a dirt ramp.
I do, however, prefer dirt trannies and landings. They feel smoother.
 

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rmb_mike said:
I started a thread with pretty much the same title a couple of years ago, only to get flamed and accused by a few ******s on here (not naming names) for trolling.
Though the thread did have a few useful tips in it.
http://forums.mtbr.com/showthread.php?t=346043
I personally like wood jumps better when you have the wood and material to build them.
Where I live, we have about 1.5 feet of topsoil, then sand or limestone; not very conducive to digging up dirt. Also, I have access to scrap lumber whenever I need it; you also don't need a crew (or expensive equipment) in order to build a wood jump in a timely manner.
I could build, say, a 4 ft tall, 4ft wide, 10 foot long wooden jump in less than a workday by myself. I could not build a dirt ramp of that size by myself in two days, let alone one.
If I ever needed to relocate a wood jump, I could do it much easier and quicker than with a dirt ramp.
I do, however, prefer dirt trannies and landings. They feel smoother.
plus DL's and DT's are safer than wood for one you don't have to worry about your front (and rear) wheel sliding if its wet. wood isnt the best for grip when its wet also wood unless treated can decompose and loose its structural integrity over time this is accelerated if the wood is exposed to the elements in this case the loss of integrity can mean that the wood you land on has the potential to break under the force of the landing thus providing in an extreme case a very bad splinter
 

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blooregard said:
plus DL's and DT's are safer than wood for one you don't have to worry about your front (and rear) wheel sliding if its wet. wood isnt the best for grip when its wet also wood unless treated can decompose and loose its structural integrity over time this is accelerated if the wood is exposed to the elements in this case the loss of integrity can mean that the wood you land on has the potential to break under the force of the landing thus providing in an extreme case a very bad splinter
You are correct. Wood can decompose and rot over time. Cheapest solution to that is to 'Thompson's Water Seal' it with used engine oil. Next cheapest solution is if you are lucky enough to have cedar trees on the land you are building, use cedar wood. It's VERY rot resistant.
The wood will not break if you build it right.
LOL...all that said DTs and DLs are better than wood, IF your situation allows dirt landers to be constructed more efficiently. As I've said, where I live and the access to lumber that I have, it's much more conducive to build wood ramps (and unfortunately landers).
 

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Jim311 said:
Wouldn't lumber soaked in used engine oil be pretty slippery when it was wet?
Technically speaking yes.
We don't 'stain' the riding surfaces, just the frame structure, and sides of the decking pieces. The only parts we actually soak/dip into the oil bucket are the post bottoms that go into the ground.
If a deck piece (riding surface) does rot or decompose, it's not like they are that difficult to replace. Replacing a deck piece of a wooden ramp is about the same as replacing a wiper blade on a car, or reshaping a rounded off lip on a dirt jump.
If you want to take the time to protect your riding surfaces, inexpensive flat color paint and some sand works really well.
Of course, if you use small cedar logs for your riding surface, you won't have to worry about soaking it in anything.
 

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ah cedar i love cedar <3 i love it when they work with cedar in my schools wood shop smells amazing :O but it is riddled with defects regardless if you want to make features with it you want to use thick large pieces for the foundation of the feature also if you have a solid log and a chainsaw you can cut grooves and ridges into the wood to make the wood grippy in wet conditions and in dry conditions
 

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Jason B. said:
A buddy added a new jump made of wood and it has no lip (flat wood is the jump surface) and I find hard to get a good jump off it. Is the technique for flat (no lip) jumps different than one with a lip?
If I'm reading the question correctly, you're asking if the takeoff from a linear takeoff is the same as a curved takeoff. The answer is no, and that you will not find pop from a linear takeoff. The only way to generate air is to either bunnyhop or carry more speed into the jump. A curved takeoff is like a progressive spring; it has a smooth ramp-up that is different the farther it progresses into its suspension. The curved lip will send you in a parabolic arc whereas a linear jump simply sends you in a line.

Bottom line is that the technique is just to hit it with speed and try and bunnyhop.
 
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