Notice: We request that you don't just set up a new account at this time if you are a previous user.
If you used to be one of our moderators, please feel free to reach out to Chris via the facebook Outerlimits4x4 group and he will get you set back up with access should he need you.
Recovery:If you cannot access your old email address and don't remember your password, please click here to log a change of email address so you can do a password reset.

Travel ramp Degree's?

General Tech Talk

Moderators: toaddog, TWISTY, V8Patrol, Moderators

Post Reply
Posts: 1768
Joined: Sun Mar 14, 2004 11:51 am
Location: Weipa

Travel ramp Degree's?

Post by crankycruiser »

we are goin to build a travel ramp between a couple of clubs down here to use for fun days etc and were wondering wat deg it is supposed to be???

thanks Ray
Posts: 322
Joined: Fri May 21, 2004 12:10 am

Post by Steve F »

22 or 30 are the normal ramp angles I think.

Cheers
Steve
Posts: 3288
Joined: Sun Feb 02, 2003 10:15 pm
Location: Central West NSW

Post by Slunnie »

I thought it was 20 or 30.
Cheers
Slunnie

Discovery TD5, Landy IIa V8 ute.
God of Athiests
Posts: 8337
Joined: Thu Aug 07, 2003 2:14 am
Location: Brownsville

Post by DamTriton »

Slunnie wrote:I thought it was 20 or 30.
x2
George Carlin, an American Comedian said; "Think of how stupid the average person is, and realise that half of them are stupider than that".
Posts: 14209
Joined: Sun Jan 11, 2004 11:36 am
Location: Adelaide

Post by -Scott- »

I thought it was 22.5 degrees - half of 45 degrees?
Posts: 1397
Joined: Sat May 29, 2004 6:58 pm
Location: West Australia Posts: Less than DeWsE

Post by jeep97tj »

30deg is the go
Shane
User avatar
stu
Posts: 913
Joined: Wed Jan 22, 2003 8:08 am
Location: brisbane

Post by stu »

i thought it can be anything.

your using a maths equation anyway to generate your RTI score.
i don't need no stinking quote for my sig. line!
Posts: 5803
Joined: Wed Feb 19, 2003 3:02 pm
Location: Brisbane

Post by ISUZUROVER »

stu wrote:i thought it can be anything.

your using a maths equation anyway to generate your RTI score.
Yep, that's what I thought too. I have seen everything between 20deg and 30 deg.
_____________________________________________________________
RUFF wrote:Beally STFU Your becoming a real PITA.
Posts: 1768
Joined: Sun Mar 14, 2004 11:51 am
Location: Weipa

Post by crankycruiser »

yer i did think it could be anything..

i reckon i'll go 30deg...

and for another question.. wat is the equation to work out ur RTI?
User avatar
udm
Posts: 659
Joined: Tue Apr 26, 2005 8:35 pm

Post by udm »

Ray, ive already got all the steel cutup for a ramp myself, and was told to go 30.

Ulises
Ulises

www.OzSigns.com - 0400008422
Posts: 1768
Joined: Sun Mar 14, 2004 11:51 am
Location: Weipa

Post by crankycruiser »

udm wrote:Ray, ive already got all the steel cutup for a ramp myself, and was told to go 30.

Ulises
kewl.. u got any ideas wat the formula is to work out the rti??
Posts: 751
Joined: Wed May 21, 2003 11:33 am
Location: Melbourne, AUS

Post by FireTruck »

If you are building the ramp for 'fun club stuff', I would go a lesser angle... say 20 or 23degrees. Much easier for novice or first timers... and they can actually make a reasonable amount of headway up the ramp.

If you are building a ramp to handle big built trucks, go 30 degrees... otherwise you will run out of ramp!

RTI is simply the distance up the ram divided by the wheelbase... and multiplied by 1000 usually. So if you go as far up the ram as your wheelbase, you score 1000. If you go less than your wheelbase up the ramp you score less than 100, etc.

It's a relative measure, but if you want to convert them you can. ie. measure on a 23 degree ramp, then convert to the equivalent of a 30 degree ramp.

S.
www.TeamFireBug.com

Thanks to:
abt4x4.com - Just Customs
Staun beadlocks - Solid Axle
Cummins - Maxxis
Posts: 5803
Joined: Wed Feb 19, 2003 3:02 pm
Location: Brisbane

Post by ISUZUROVER »

RTI = H/sin(A*pi/180)/W*1000
D = H/sin(A*pi/180)

H = height of tyre (on ramp) above ground
A = angle of ramp
D = distance travelled along ramp
W = wheelbase

Length units must be consistent (all " or all cm, etc)
_____________________________________________________________
RUFF wrote:Beally STFU Your becoming a real PITA.
Posts: 1768
Joined: Sun Mar 14, 2004 11:51 am
Location: Weipa

Post by crankycruiser »

ISUZUROVER wrote:RTI = H/sin(A*pi/180)/W*1000
D = H/sin(A*pi/180)

H = height of tyre (on ramp) above ground
A = angle of ramp
D = distance travelled along ramp
W = wheelbase

Length units must be consistent (all " or all cm, etc)
umm thanks..


can u put it in english now please :? :D
Posts: 5803
Joined: Wed Feb 19, 2003 3:02 pm
Location: Brisbane

Post by ISUZUROVER »

crankycruiser wrote:
ISUZUROVER wrote:RTI = H/sin(A*pi/180)/W*1000
D = H/sin(A*pi/180)

H = height of tyre (on ramp) above ground
A = angle of ramp
D = distance travelled along ramp
W = wheelbase

Length units must be consistent (all " or all cm, etc)
umm thanks..


can u put it in english now please :? :D
You wanted the formula - do you need a lesson on how to use a calculator? :lol: :finger:
_____________________________________________________________
RUFF wrote:Beally STFU Your becoming a real PITA.
Posts: 297
Joined: Wed Jul 12, 2006 6:32 pm
Location: cranbourne, vic

Post by g60boy »

crankycruiser wrote:
ISUZUROVER wrote:
RTI = H/sin(A*pi/180)/W*1000
D = H/sin(A*pi/180)

H = height of tyre (on ramp) above ground
A = angle of ramp
D = distance travelled along ramp
W = wheelbase

Length units must be consistent (all " or all cm, etc)


umm thanks..


can u put it in english now please


You wanted the formula - do you need a lesson on how to use a calculator?
im a dumb a$$ boiler maker and it works fine on my calculator. :D :finger:
mq shorty, black, rust free!!, quarter chop, F&R tube bars and sliders, q78's or 33'' stt's, 4.88's with lsd waiting to be thrown in.. :D http://www.patrol4x4.com/forum/showthread.php?t=9540
Posts: 751
Joined: Wed May 21, 2003 11:33 am
Location: Melbourne, AUS

Post by FireTruck »

...very complicated way of saying:

RTI = (distance up ramp / wheelbase)*1000

S.
www.TeamFireBug.com

Thanks to:
abt4x4.com - Just Customs
Staun beadlocks - Solid Axle
Cummins - Maxxis
Posts: 5803
Joined: Wed Feb 19, 2003 3:02 pm
Location: Brisbane

Post by ISUZUROVER »

FireTruck wrote:...very complicated way of saying:

RTI = (distance up ramp / wheelbase)*1000

S.
Yes but it corrects for different ramp angles. Your formula is fine if you want to compare vehicles on the same ramp.
_____________________________________________________________
RUFF wrote:Beally STFU Your becoming a real PITA.
Posts: 751
Joined: Wed May 21, 2003 11:33 am
Location: Melbourne, AUS

Post by FireTruck »

um... no, it doesn't correct for the angle.

The formula D = H/sin(A*pi/180) is simply converting the height off the ground to the distance up the ramp... as in:

Sin (angle) = opposite / hypotenuse

So converting that to find the hypotenuse (or distance up the ramp), you have to take:

hypotenuse = opposite/sin(angle)

In your case the opposite is the distance off the ground, and the angle is the ramp angle. The angle has to be in radians though, so to convert to radians you have to multiply by pi/180

Soooo.... it does not correct for the angle, it simply uses the angle to calculate the distance up the ramp.

You can do the same thing by actually measuring the distance up the ramp... no calculator required.

S.
www.TeamFireBug.com

Thanks to:
abt4x4.com - Just Customs
Staun beadlocks - Solid Axle
Cummins - Maxxis
Posts: 2526
Joined: Wed Sep 01, 2004 8:21 am
Location: Outcast Offroad

Post by Micka »

FireTruck wrote:um... no, it doesn't correct for the angle.

The formula D = H/sin(A*pi/180) is simply converting the height off the ground to the distance up the ramp... as in:

Sin (angle) = opposite / hypotenuse

So converting that to find the hypotenuse (or distance up the ramp), you have to take:

hypotenuse = opposite/sin(angle)

In your case the opposite is the distance off the ground, and the angle is the ramp angle. The angle has to be in radians though, so to convert to radians you have to multiply by pi/180

Soooo.... it does not correct for the angle, it simply uses the angle to calculate the distance up the ramp.

You can do the same thing by actually measuring the distance up the ramp... no calculator required.

S.
All of this just to be a farkin ramp queen :roll:

:finger:
Posts: 1544
Joined: Fri Jan 03, 2003 10:33 am
Location: Wahgunyah(REDNECK WONDERLAND) Victoria

ramp

Post by Webbie »

FARKKKKKK :shock: i didn't realize you had to have a whirlybird hat to work out the winner on a Travel RAMP :roll: i thought those equations were just to piss people off in school :lol: :armsup:
Lockers or Knockers ,both will make for fun.

HYBRID 4B PRDUCTS Visit Tigerz11 here http://www.tigerz11.com.au/ and LOCKTUP 4x4 here http://www.locktup4x4.com.au/ cheers

www.trailtrack4x4.com
Posts: 751
Joined: Wed May 21, 2003 11:33 am
Location: Melbourne, AUS

Post by FireTruck »

You don't... that's what I'm trying to say.

You measure your wheelbase, and how far up the ramp you go, then divide one by the other.

If you measure the RTI on a 20 degree ramp, then want to see what it would be on a 30 degree ramp, THEN you have to use some math.

OR, if you lift your tire up with a fork lift you can measure how far off the ground it ends up and then convert that into an RTI at a given ramp angle... you need to do some math.

The RTI is depndant on the angle of the ramp... an RTI of 1000 on a 30 degree ramp is equivalent to an RTI of 1280 on a 23 degree ramp, and 1462 on a 20 degree ramp.

S.
www.TeamFireBug.com

Thanks to:
abt4x4.com - Just Customs
Staun beadlocks - Solid Axle
Cummins - Maxxis
Posts: 3288
Joined: Sun Feb 02, 2003 10:15 pm
Location: Central West NSW

Post by Slunnie »

IF maths is not your forte, than this may be easier:

http://www.snakeracing.com.au/2001/rticalculator.shtml
Cheers
Slunnie

Discovery TD5, Landy IIa V8 ute.
Posts: 5803
Joined: Wed Feb 19, 2003 3:02 pm
Location: Brisbane

Post by ISUZUROVER »

The FIRST formula I posted (you quoted the 2nd) does correct between ramp angles, and gives the same results as you posted.
FireTruck wrote:um... no, it doesn't correct for the angle.

The formula D = H/sin(A*pi/180) is simply converting the height off the ground to the distance up the ramp... as in:
FireTruck wrote:
The RTI is depndant on the angle of the ramp... an RTI of 1000 on a 30 degree ramp is equivalent to an RTI of 1280 on a 23 degree ramp, and 1462 on a 20 degree ramp.

S.
_____________________________________________________________
RUFF wrote:Beally STFU Your becoming a real PITA.
Posts: 751
Joined: Wed May 21, 2003 11:33 am
Location: Melbourne, AUS

Post by FireTruck »

Dude - it doesn't correct for the ramp angle - it USES the ramp angle to calculate the distance up the ramp... which you can easily measure rather than using a complex calculation and confusing everyone (like I will now).

It is simple trig...

Sorry everyone - please change the channel now...

sin(angle) = opposite / hypotenuse

The angle is the ramp angle, the opposite is the distance of the tire from the ground, the hypotenuse is the distance up the ramp... if you were to complete the triangle, the 'adjacent' would be the distance along the ground to the point directly under the tire.

The only time you need to use this math is if you don't have a ramp at all... if you have a ramp you can just use a tape measure.

Here is your original formula...

RTI = H/sin(A*pi/180)/W*1000

H = height of tire off ground
A = ramp angle
D = distance travelled up ramp

and D = H/sin(A*pi/180)

soooo, you can either measure D with a tape measure (along the ramp), or calculate D by measuring H (the height of the tire off the ground) then using the (complicated) formula to calculate D... why bother? You have to measure once anyway, why not just measure D???

If you measure D with a tape measure, your formula becomes (by simply substituting your second formula):

RTI = D/W*1000

...look familiar??

To be clear(?), the math is correct... but overly complex and not needed for a simple ramp day kind of a thing. It doesn't correct for the ramp angle, it uses the ramp angle to calculate the distcnce up the ramp. The original question was about someone building a ramp, who wanted to know "what's the formula to measure the RTI"... you don't need to take the sin of angles etc to calculate an RTI on a given ramp - you just need a tape measure and you can do a simple calc on your phone to divide a couple of numbers.

When do you NEED to use this math?? If you don't have a ramp at all and you are just picking your tire up with a fork lift. Or, if you have a 23 degree ramp and you want to compare (not correct, compare) your score to the 30 degree ramp from Tuff Truck... then you use the math to calculate what your RTI would be on a different ramp angle.

Sorry all, I'm done now... too much high school math for 1 week.

S.
www.TeamFireBug.com

Thanks to:
abt4x4.com - Just Customs
Staun beadlocks - Solid Axle
Cummins - Maxxis
Posts: 818
Joined: Thu Nov 20, 2003 9:06 am
Location: Bathurst NSW

Post by professor »

RTI should take the width of a rig into consideration aswell (wider track will go further up the ramp) Work that into the formula :lol:
Posts: 70
Joined: Fri Aug 27, 2004 11:58 pm
Location: South Africa

Post by Freakazoid »

Hey Professor, thats what we do. We take normal RTI as in distance up ramp/wheelbase, but we add another score which is basically the distance between the centres of the wheels across each other. Like in distance between front left and rear right and then divide this into distance up ramp. Makes some of the narrower vehicles look better compared to the really wide comp trucks.
94 GQ, Air Suspension, 35's, Soon to have VH45
Posts: 818
Joined: Thu Nov 20, 2003 9:06 am
Location: Bathurst NSW

Post by professor »

Freakazoid wrote:Hey Professor, thats what we do. We take normal RTI as in distance up ramp/wheelbase, but we add another score which is basically the distance between the centres of the wheels across each other. Like in distance between front left and rear right and then divide this into distance up ramp. Makes some of the narrower vehicles look better compared to the really wide comp trucks.
Little more level playing field.

that would make the wheel base look longer for the wider trucks.

:cool:
Posts: 352
Joined: Mon Dec 23, 2002 9:10 pm
Location: Sydney

Re: Travel ramp Degree's?

Post by 65Mog »

crankycruiser wrote:we are goin to build a travel ramp between a couple of clubs down here to use for fun days etc and were wondering wat deg it is supposed to be???

thanks Ray
If it's for a club, Id make it 23 degree's, if you have any standard 4wds in the club they will be lucky to drive a couple of feet up a 30 degree ramp, some new 4wds don't even have a 30 degree approach angle.
Posts: 1768
Joined: Sun Mar 14, 2004 11:51 am
Location: Weipa

Post by crankycruiser »

Well thanks 4 all the input guys..

im gunna make it 23deg and long enuf so the decent trucks dont drive off the end of it ;)

Ray
Post Reply

Who is online

Users browsing this forum: No registered users and 3 guests