1994cr125

Member
Jul 10, 2007
11
0
I am building my first table top jump. I had a few questions. The take off is going to be small, 4 feet at the lip and id like to make the whole ramp 6-8 feet wide all made from dirt.
1st? is there any guide line to follow for the angle of the take off and landing
2nd? how long should the top of the table top be for a successful landing on the landing ramp.
3rd? any other tips suggested would be appreciated.

Thanks guy.
 

GoT_GreeN

Member
Jun 17, 2007
66
0
They are guidlines to building jump faces correctly. A pro scale jump face is on a 2:1 ratio ( meaning for every foot high the jump is the ramp goes out 2 foot. For instance, a 4 foot jump would have a a ramp extending out 8 foot from the center to the toe of the ramp. You don't measure from the peak down. The best way to get this right is start of by driving two stakes, making sure you have enough to leave 4 foot sticking up on the ouside of the jump where the center is going to be. Now measure from the base of the stakes out 8 foot. Amature scales can vary but are usualy 3:1 and you use the same methode as above to do this also. Tables are figured the same for the on rapm but different for the off. For the off of a table you take the width of the top and add the same to it. A 40 foot long table would ramp off from the off end lip out 80 foot and not measure from the lip, measured from the base in line with the lip.
 

olderndirtmom

Member
Apr 28, 2007
424
1
GoT_GreeN said:
They are guidlines to building jump faces correctly. A pro scale jump face is on a 2:1 ratio ( meaning for every foot high the jump is the ramp goes out 2 foot. For instance, a 4 foot jump would have a a ramp extending out 8 foot from the center to the toe of the ramp. You don't measure from the peak down.
?

GoT_GreeN said:
The best way to get this right is start of by driving two stakes, making sure you have enough to leave 4 foot sticking up on the ouside of the jump where the center is going to be. Now measure from the base of the stakes out 8 foot.
What?

GoT_GreeN said:
Amature scales can vary but are usualy 3:1 and you use the same methode as above to do this also. Tables are figured the same for the on rapm but different for the off. For the off of a table you take the width of the top and add the same to it. A 40 foot long table would ramp off from the off end lip out 80 foot and not measure from the lip, measured from the base in line with the lip.
Huh? You mean length, don't you?

Not meaning to be a jerk here... but.. "height, width, length...hypotenuse... parallel...perpendicular to, rise, run...slope ...


A teeny bit of precision of language would help immensely. As written this is- to put it gently- a mess. Not disputing the accuracy of the ratios...

http://www.dirtwurx.com/track_tips4.php
 
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1994cr125

Member
Jul 10, 2007
11
0
I get what he's saying. I'm going to draw up some plans and post them if i can

what about the landing ramp. i heard it should be 16 feet long since the height is 4 feet.
 

olderndirtmom

Member
Apr 28, 2007
424
1
1994cr125 said:
I get what he's saying. I'm going to draw up some plans and post them if i can

what about the landing ramp. i heard it should be 16 feet long since the height is 4 feet.

According to GoT_GreeN, It depends on the length of the table top.

I believe he said to double the length of the table top.
 
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olderndirtmom

Member
Apr 28, 2007
424
1
It's just math 1994 cr125. You can do this.... Or... perhaps you could make it shorter and borrow from the (ack!) quad forum. 3 1/2 feet tall 3:1 rise on the launch end.

http://forums.atvconnection.com/messageview.cfm/catid/16/threadid/467944.cfm

Look at the last post. (Approach is 10', top is 9, off ramp is 18'- again all measured in a straight line on the ground.....A total of 37' linear run.)

I'd hidely recommend you read the Durt Wurx article.

Here's some numbers for a 4' table top based on GoT_GreeN's formula for amateur's:

12' approach, 10' top, 20' exit (42' straight line on the ground)..... If you want to measure along the ramps themselves add a bit over a half foot on the approach, and just under half a foot on the exit .

(Simple Geometry).

Perhaps one of our engineering students has a formula for the perfect curve of the bowl?;)

Well, that ought to be clear as mud. :whoa:
 
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1994cr125

Member
Jul 10, 2007
11
0
Thanks i think ill be able to do this. luckily my dad has got a friend with a bobcat he'll let me borrow. so ill be sure to take pics of the ramp as i begin. i expect to start sometime in august but plans could be thrown off easily.

but i still have one small question. what should the curve of the take off be.
 

olderndirtmom

Member
Apr 28, 2007
424
1
1994cr125 said:
but i still have one small question. what should the curve of the take off be.

The million dollar question....


Jeopardy theme....Now to turn it over to someone who actually knows something about riding. lol :rotfl: :rotfl:

You don't want to get your fanny kicked by having it give you too much loft (nose or tail). I'm sure someone here has a formula for the arc....
 
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Moparman1539

Member
Sep 9, 2006
804
0
1994cr125 said:
Thanks i think ill be able to do this. luckily my dad has got a friend with a bobcat he'll let me borrow. so ill be sure to take pics of the ramp as i begin. i expect to start sometime in august but plans could be thrown off easily.

but i still have one small question. what should the curve of the take off be.

Well.. thats up to you.. how i made a jump was make it the eit and length and everything then i added dirt to teh front, i started with a long gentle takeoff ramp to see what it would do.. then modified it from there...

Steper = Hight
flater = your gonna go far straight..

Also for the curve... You dont want it real curvy, just a good smooth transition from the bottom to top.. Or whatever feels comfortable.. Remember if you dont like it you can always add or take off some dirt...

Im not really sure if that helped.. but thats my $0.02
 

_JOE_

~SPONSOR~
May 10, 2007
4,697
3
We always use trial and error. Figure out how fast you WANT to be going to clear the jump(how much lead and distance to next turn/jump), build it so it looks close and try it. If you come up short, cut the lip angle down a bit. If you over-clear it either lenghten the jump or steepen the lip. Whatever you do MAKE SURE YOU PACK IN THE LIP VERY WELL. I've seen what happens when you try to hit a soft lip, not pretty! Good luck and have fun :cool: .
 

Solid State

Member
Mar 9, 2001
493
0
olderndirtmom said:
The LINKS were the point, goofy. :rotfl:

It's called "Here's the information".

Oh... Poster... "Would you read it for me and tell me what it says?" :coocoo:

Uh, yeah.. sure. :bang: :bang:

:fft:

My point was that the spelling in this thread was horrible and the descriptions were so woefully non-specific that only the links were of any value - should you care to click on them after suffering through all the thread dribble.
 

GoT_GreeN

Member
Jun 17, 2007
66
0
I'm not always perfect in the way I word things, especialy when I'm in a hurry but got the point across. Instead of none constuctive put downs why didn't you simply clear things up with your vast intelect, (olderndirtmom) and type it the way it was ment to be, your way!!
 

olderndirtmom

Member
Apr 28, 2007
424
1
Got_Green: Actually, I tried to. I found the links with longer more thoughtful replies. Found the links with a similar formula worked out for the poser. I even did the math on the 4 foot for the poster. I wrote it out long hand, with proper verbage (which I found incredibly difficult and worst yet, it confounded 1994cr125 even more).

Furthermore, Solid State indicated the entire thread was meaningless jibberish and totally unhelpful. So, I edited out the longer more wordy version and left the links in the hope that at least something would be helpful. I can't delete my posts, unfortunately, or I might have done that. I, too, am often in a hurry, or think of a better way to say things later. I can't delete my posts, but I can edit them.

And that is exactly what I did here. I stood corrected by 1994cr125, Solid State and yourself as to my own ability to clarify things. Apparently even proper verbage was totally unhelpful to anyone reading.

So I edited.

A useful tool. If you feel your post is useful and helpful and articulate as written, that is great. I support your freedom of expression completely. My opinion was that I could figure out what you meant, but that it could be said more clearly using either geometry terms or construction/carpentry terms. It's simply my opinion. It can cause you no harm if you find no value in it. It's like liking chocolate ice cream, a preference. I value things like precision in language. I value spelling. I value punctuation. I value understandable sentences. Just my thing. The more complicated the topic, the more I find it helpful.

However, I also value kindness and a willingness to help others. I wouldn't want to deter you from that in any way. Not my intent at all. This forum is nothing without those who are willing to help. For that I am truly sorry.

I believe 1994cr125 indicated he got everything he needed from your post. That is the important thing, right? That you were helpful to him? My opinion matters not one iota as you were trying to help him, not me.

Seems to me like you accomplished your mission. I applaud your willingness to be helpful. It's a very nice thing.
 
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The Redrider

Member
Jun 14, 2019
238
31
The links in the thread do not work. Anyone know how to access them? Thanks!
Are you wanting to know how to jump a table top? Just a Okie anyone else directly, its simple, practice, crash, practice some more, crash, rinse and repeat. LOL! It dont get mo easier!!!!!
 

get2bill

Member
Mar 3, 2008
8
2
Maryland
Are you wanting to know how to jump a table top? Just a Okie anyone else directly, its simple, practice, crash, practice some more, crash, rinse and repeat. LOL! It dont get mo easier!!!!!

Sorry for the delay. First I really liked your video. Do have any idea how long and how high the table top you were jumping was? I'm getting ready to build one and that looks about what I have in mind. Thanks!
 

The Redrider

Member
Jun 14, 2019
238
31
Sorry for the delay. First I really liked your video. Do have any idea how long and how high the table top you were jumping was? I'm getting ready to build one and that looks about what I have in mind. Thanks!
My friend, I used that video as an example. I have a picture of me long ago for you to observe moi' on a 1988 KX-125, you will notice the rider parked observing me floating on bye. LoL! Sorry for the confusion, but the vid I used is a clip of another rider to show you how its done. I usually don long jumps and avoid too much height, it keeps me low to the ground and to maintain speed. I cant count on my toes and feet how many crashes, and helmets I have cracked open during my years of racing and riding, but rest assured im learnid now. Approach a hill in 3rd gear and pin it, be sure to stand on your pegs during the ordeal. As you leave the lip of the hill, blip the throttle if the front wheel dropps, and tap the rear break if your front wheel goes too high! Practice makes perfect, make sure you life insurance is paid up, LOL! First picture is skinny me back in the day, the last piccy is my now before Jenny Craig! LOL! Good luck! And as we 80's dudes say in Moto-x back in the day keep on head banging!
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