1. The most important thing about buying a new bike is to make sure it fits. The only way you'll know if the bike is right for you is to size up the bike and make sure that the bike's geometry matches your body's geometry. Ask questions and do some research.
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2. If possible, try to find a shop that will let you demo the bike on real dirt. Five minutes in a parking lot won't cut it. You wouldn't buy a car without a real world test drive, and a bike should be no different.
3. Don't belive the hype. Just because your favorite rider or best friend rides a certain bike, that doesn't mean that's the best one for you. Have an open mind and be realistic about your needs and ability.
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  1. #1
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    Building obstacles out of wood 2x4's?

    So I want to work on getting my bike over fallen trees.... Thinking about just nailing together (safely =p) a bunch of 2x4's to simulate a fallen tree. What do you guys think?

  2. #2
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    You can pick up free "firewood" on Craigslist all the time. Seems like that might serve the purpose.

  3. #3
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    I started with a 4X4 and then moved up to a concrete block. Worked for me.

  4. #4
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    Take a couple of 2x4 and make a way to hold them upright. Put nails in them at predetermined heights and rest a dowel on the nails between the "posts". This way if you can't make it over the height the dowel will just roll off the nails and not hurt you or your bike.

    Sent from my DROID RAZR using Tapatalk 2

  5. #5
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    Perfect thank you. Dowel it is.

    So another thing I want to do is make platforms to practice getting over obstacles and dropoffs (maybe just as high as 3 feet for now).
    So looking at this video Think Bikes Tutorials - 11 - Dropping Off - YouTube

    I see pvc tubing with joints (or is that too weak? I weigh 175 and my bike weighs 28 lbs). What's the surface I should look for?

  6. #6
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    I think that if you are going to be using PVC to make platform supports you are going to see a lot of play and wobble in the platform. PVC pipe isn't the most ridged of materials. You might look into steel pipe and fittings, or using wood and building a lattice skeleton. I would think some basic plywood would make a decent surface as long as you support it correctly underneath.

  7. #7
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    Hmm. Worried about the play and wobble, maybe I can use pvc cement or whatever to solidify it. Really hoping for something relatively portable and lightweight. Was thinking I could make little feet and use electrical tape to make a sticky/soft feet.

  8. #8
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    Quote Originally Posted by sujianhua View Post
    Hmm. Worried about the play and wobble, maybe I can use pvc cement or whatever to solidify it. Really hoping for something relatively portable and lightweight. Was thinking I could make little feet and use electrical tape to make a sticky/soft feet.
    Not to rain on your parade...but geez....

    Toss some 2 x 4 on the grass and ride over them....

    If you can't find a log or something....Most logs I end up riding over are not firmly fixed either.

  9. #9
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    Actually I'm wanting to get the platforms up to 5-6 feet tall ^_^. Bunny hop/pedal up a couple steps, do a big drop off...

    Basically if I do use PVC, I'd use fittings to form a cube frame just like the link above, plus some supports since it'll be thin plywood. Went to Lowes and checked out the PVC, seems like 1 1/2" is going to be solid enough, maybe I can get the frame to stick without glue because the fittings were pretty tight.

  10. #10
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    if you are looking for portable, maybe something involving stepstools and sawhorses to hold up platforms made of plywood. still sounds rickety (you're gonna die), but it would be better than pvc pipe.
    Last edited by Bill in Houston; 07-18-2012 at 12:49 PM.

  11. #11
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    Quote Originally Posted by sujianhua View Post
    Actually I'm wanting to get the platforms up to 5-6 feet tall ^_^. Bunny hop/pedal up a couple steps, do a big drop off...

    Basically if I do use PVC, I'd use fittings to form a cube frame just like the link above, plus some supports since it'll be thin plywood. Went to Lowes and checked out the PVC, seems like 1 1/2" is going to be solid enough, maybe I can get the frame to stick without glue because the fittings were pretty tight.
    Picnic table

  12. #12
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    We used to scavenge lots of old stuff to build trials courses in the backyard. Stacks of old pallets, some old 4x4s, a big wooden cable spool or two if you can find one... Lots of options that you can use on the cheap.

    And like above, picnic tables are pretty versatile (if you don't mind dinging them up with chainrings and whatnot).

  13. #13
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    Quote Originally Posted by sujianhua View Post
    Actually I'm wanting to get the platforms up to 5-6 feet tall ^_^. Bunny hop/pedal up a couple steps, do a big drop off...

    Basically if I do use PVC, I'd use fittings to form a cube frame just like the link above, plus some supports since it'll be thin plywood. Went to Lowes and checked out the PVC, seems like 1 1/2" is going to be solid enough, maybe I can get the frame to stick without glue because the fittings were pretty tight.
    Dude, have you made anything out of PVC before? It is not a structural material, at all. I built a hockey net out of it when I was younger and it barely held together for that purpose, I wouldn't even consider building a weight bearing structure out of it.

    Wood is the way to go, have a look in the trail building section and look up people building obstacles. Obviously for home use you don't need to build quite as robustly but you do need to have an idea of how to brace things, how to properly build things, and you should get a few design concepts in place before you go buying material.

    Remember, if you do want a platform 5-6' high you need to have enough room up there to actually have a bike and either get set to drop off of it or be able to come to a stop when you get on top of it which means a pretty sizable chunk of platform.

    What I would do is look up skate ramp plans in particular ones for a "fun box". You can find plans for one in an almost infinite set of dimensions and it will also show you how to build a ramp for it. A ramp is good so you can either ride off or onto the box, gives you another option, and you could build a jump on one side of the box to land on the ramp on the other side while leaving the opposite sides as drops. Or any combination of ramps/drops/jumps.

    This thing is pretty awesome, as an example:
    Don't you hate it when a sentence doesn't end the way you think it octopus?

  14. #14
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    The link of the built platforms were made using metal pipe. 1 1/2" pvc is pretty strong if its axially loaded, but it is also fairly brittle. It would probably work okay if you were just dropping off the platform, but if you were going to be landing or jumping onto the platform, or impact loading the pvc in any way I would be hesitant to use it.

  15. #15
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    I agree on not using PVC. It's way too flexy. We just built a structure out of 2" PVC for some underwater LED lights for my friend's boat dock and although it was great for that application, there is no way I would want to ride up it and jump off of it.

  16. #16
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    Thanks guys, I really appreciate the help. I'll look at building it out of wood instead of pvc

  17. #17
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    Quote Originally Posted by sujianhua View Post
    Actually I'm wanting to get the platforms up to 5-6 feet tall ^_^. Bunny hop/pedal up a couple steps, do a big drop off...

    Basically if I do use PVC, I'd use fittings to form a cube frame just like the link above, plus some supports since it'll be thin plywood. Went to Lowes and checked out the PVC, seems like 1 1/2" is going to be solid enough, maybe I can get the frame to stick without glue because the fittings were pretty tight.
    Umm if you're asking in the beginner forum I have to ask what bike are you riding that you think it's ok to do a 5-6 ft drop to flat?
    13 Lenz Lunchbox punkass

  18. #18
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    Fuel EX 9 - Trek Bicycle

    I got it as a demo bike, $2000

  19. #19
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    Quote Originally Posted by sujianhua View Post
    Fuel EX 9 - Trek Bicycle

    I got it as a demo bike, $2000
    Yea, good luck with that. Not being rude, jumping bikes from that height to flat just isn't a good idea. Yes it's called a mountain bike, but they have limitations.

    When you read about or see people doing big drops they are landing on a transition- the landing is going down hill.

    Even landing on a transition, 5-6 ft drops I think are outside of what the EX line is designed for.
    Last edited by TwoTone; 07-18-2012 at 04:25 PM.
    13 Lenz Lunchbox punkass

  20. #20
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    Hmm, thanks I'll keep that in mind. Maybe I won't get above just a few feet, I'll be working my way up and I may just decide that after a few feet I'm not comfortable dropping from higher and landing flat like that.

  21. #21
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    Just some quick physics. Impact force of 203lbs from 6ft vertical drop with 120mm suspension is in the ball park of 1300lbs of instantaneous force. Give or take a few hundred.

  22. #22
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    i'd stick with 2-3 ft drops, if your new to drop offs like i was, it doesnt sound high, but its a diff story when you actually try riding off it. to me for ever to get the balls to do it, just because im one of those people that actually think " okay i could break this, or this or this, and keep me out of work, lose my job, go homeless, have to sell my bike....." -_- think before you do.

    Nice bike though, i envy

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