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Discussion Starter #1
I went to a meet and greet and ramped an 89.5 on a 30 degree ramp?

How do I figure my score???
 
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Discussion Starter #2
Typically it is your ramp measurement divided by your wheelbase.

Ron
 
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Discussion Starter #4
Oh yeah, and the one at the bottom is Mine and Mike's dualing Rubi's...
 

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PBR Stitch said:
Typically it is your ramp measurement divided by your wheelbase.

Ron
vertical from the center of the hub correct?


edit: i was standing right there when wrath went up. i think he had a bit more to go before his tire would have lifted.
 
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Discussion Starter #6
I was try'n to ask them questions about the specifics of their ramp and they were just kind of blow'n me off.....

And when I went up, the guy that was measuring with a carpenters square was no where to be found....

It looks to be over 1100 as a quick check with the tape by me with my SO taking pics was around 55"....

It sure looked cool, I was smilling in the picture because the crowd sort of gasped, I knew it was pretty high at least in comparisons to all the other vehicles anyways. I asked the spectator if all three wheels were on the ground.
 
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Discussion Starter #7
Here is my opinion on Ramps:

I use ramps mainly to check clearance and rub issues. It's nice to be able to flex it and see what rubs and what doesn't.

Here is the basic problems with a ramp.
1) The people measureing, unless it is the same guy for every measurement, doing it exactly the same way the measurements will change.
2) Tire pressure, try this experiment one time. Run the ramp at street pressure, then run the ramp at trail pressure. You will get a better score at trail pressure.
3) Tire placement. The tire needs to be run on the ramp near, but not over the edge of the ramp. I've seen them run up the edge of the ramp with half the tire off the side of the ramp (i.e. hanging below = larger score)
4) The Ramp construction. Take a look at the mesh on the ramp and see if is pushed down or is pushing down with the weight of the tire. If it is you can actually get a higher score.
5) Take identical rigs, but with different tires and run the Ramp You will get different scores. Now run identical rigs, but have one with a wider axle. The wider axle will get a better score because we do not calculate for axle width. example would be a rig that could rotate its front axle completely vertical. With a 36" axle it would only be able to get up the ramp about 34" vertical height (compensate for tire on ramp and other tire hitting ramp) now, put a 48" axle on this rig, guess what, you could now go up about 46". Who has greater flex? In reality neither.
6) The number of times you run it up the ramp before you measure. I never thought about this until I saw an actual ramp competition and one of the guys mentioned it. Limbering up the springs is the way it was described. I tried it and got a better ramp score, not much, but better.
7) Reality wheelbase measurement. Actually measuring from hub center to hub center, then comparing the ground measurement to the ramp measurement of wheelbase.
8 ) Ground slope the ramp has to be perfectly level in all aspects. Not very likely. Also the surrounding area has to be perfectly level so that all the tires of the ramping vehicle have to be on the same plane as the ramp.

In my opinion the best way to run a ramp score (at least until I figure out the axle width computation, and build a 3d laser holographic terrain mapping and vehicle ramping system :roll: ) is to measure from the ground to the lowest part of the tire on the ramp squared off of the ramp (takes away possible ramp ground slope). This will give you height to ground. Put it in to the calculation below and it will give you a ramp score. Any monkey with a level can do this height.

(Tire height/ sin(ramp angle))/ wheelbase * 1000 = ramp score

Examples: (I used my scores with my known measurements.)
(33.5/ sin (20))/ 93.4 * 1000 = 1048.68 ramp score
(33.5/ sin (23))/ 93.4 * 1000 = 917.95 ramp score
(33.5/ sin (30))/ 93.4 * 1000 = 717.34 ramp score

Ron
 

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Looks good, and Mikes rig (?) looks good too...

Ken
 
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Discussion Starter #10
>I use ramps mainly to check clearance and rub issues. It's nice to be able to flex it and see what rubs and what doesn't.
>
>

Thanks for the great post, I will ramp completely different next time.

The ramp does appear to be 20 degree not 30 degree as was his sort of answer when I asked.


1. Air down
2. diconnect rear sway bar
3. run the ramp a few times first
4. stay as close to the edge as possible

Thanks for the great post on it all!!!
 

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you could cheat, and run trail pressure on the ramped side, and street pressure on the ground side...might give you an extra couple inches


notthat i have ever cheated at anything in my life....i'm honest :D
 
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Discussion Starter #12
That was the first ramp I have ever run.....

I'm sure I can do better.

I did briefly put the tape measure there on the ground up to the center of the wheel level.

That was about 54" to 55", but knowing what I know now about ramping, I don't think I can gauge any sort of accurate score from the experience.

I guess you don't really need a score to see it was flex'n like a Mo Fo!!! lol

Since I had never ramped before, I was eager to see.
 

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Another big problem is that different people measure in different ways the :wink: "correct" way (original way) is to measure with a plumb line down to the ramp. It has become common to use a square instead, which gives higher scores.
 
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