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How are whoops formed?

BEEF706

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#1
Okay, guys and gals, this is my stupid question of the day. The other day VintageDirt and I were out for a desert ride and when we stopped to rest ( hush young people), we began to wonder what exactly were the forces that formed the three foot deep whoops we were just being slammed by. I mean I guess that I understand the basics, but why do they get deeper if we mostly ride the tops? :| This is actually a real question, VD and I put our considerable brains together and couldn't come up with anything that sounded convincing, so I am calling on the resources of my favorite bit of cyberspace to help me out here. Anyone?
 

KWJams

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#2
Same way wash board roads get wash boarded

(insert Rod Sterling voice)
Imagine if you will that you are riding in a totally different dimension on a freshly graded gravel road. (voice off) ;)
Every time the springs bounce, it will result in enough inertia to start the creation of a depression in the road.
Wash boards are the results of spring bounce.
On open trails I have noticed where a b-ush or a rock gets ridden over the soil holds together long enough to create a depression on both sides which will become a set of whoops. :)

Of course this is only an opinion that I have come to a conclusion of in my own mind :silly: after miles and miles of staring through the windshield of a very larger truck.
 
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#3
Being the rider of an open class 20 y.o. thumper, i have come to the conclusion that whoops were put there by the devil. :p
It seems like every time i get some decent speed up out here in the desert, i come around a corner and presto there they are!!
yards and yards of those &^%$# things......
But Beef and Vintage have it easy riding those well suspended mini bikes..... ;) :eek:
 

909

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#4
on the second day god said let there be light....and there was... and it was good

4 days pass

On the seventh day god rested, and on any given sunday he went out to ride.

The devil :p saw god, having fun, and this made him jealous.... And he made whoops. And he saw that they were good. :silly:

yeah my sunday school teacher rode


that my friends is the story of the whoops..... :scream:
 
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#5
Just a thought, but maybe they don't get deeper, just the tops get higher!
That makes no sense :think: Another thought, they began as acceleration bumps, the occasional rain settled into the low areas and sank in, causing the ground to sink. A little more rain, puddles up, sinks in, ground sinks a little more, repeat, repeat, repeat. No scientific data to back that up, just a guess. :cool: One more thought, quads ride in the area :scream: and can't carry enough speed to skim the tops. They ride over the humps, spin in the bottom causing the low area to get deeper plus they throw dirt onto the high area causing them to get higher. Or could it be just plain ol' erosion, wind, rain and such. :D
 
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#6
Whoops are not the tool of Satan. They are placed by there by the Almighty himself. A gift from above.....After granting the knowledge of rising rate and long travel suspension, he did not want this to be squandered on groomed tracks that were smoother than roads. So on the 8th day he created whoops and time to ride......Later to be smote down by his wife, whom later defined day of rest as cleaning the garage....... :(
 

WoodsRider

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#7
Years ago our forefathers they didn't "skim" the tops of whoops. Of course to them a Triumph was the ultimate enduro mount. :scream:
 

XRpredator

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#8
Re: Washboarded roads

It ain't just spring bounce, KW! As a former grader operator, I have mucho experienco with the washboards. If you can blade a road wet, get it nice and smooth, and let it bake dry, it will last a long time without needing more attention.

Now when you have to dry-blade, it's altogether different. Spring bounce is a factor, but so is speed. As soon as you start making dust, you start taking the "binder" out of the road, making the larger aggregate rise to the surface. This will increase the spring bounce, which, if everyone would drive slower, would not be a problem. Unfortunately, people don't understand slow, so they start hammering the road, causing the washboards. I think front wheel drive cars have exacerbated the problem.

As for the whoops (getting back on topic!), I think it is a combination of the # of bikes, wind, speed, rain, etc. I've seen roads get a little "whoopy", then not be ridden on for a while, but I come back and its a whooped out wonderland!
 

CanadianRidr

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#9
Are you guys positive it's not just the whoops gnomes? ;) They come to our tracks in the middle of the night and dig the bottoms of them out with there little shovels. Then you come to the track next day and BANG.......you knew they weren't that size the day before......If you hear little giggles from the bushes you know the gnomes have attacked! :debil:
 

KWJams

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#10
Re: Same way wash board roads get wash boarded

Originally posted by KWJams

Wash boards are the results of spring bounce.
:silly: I posted that while buzzing on a sugar high from my B-Day cake and forgot to add --- acceleration which in part causes spring bounce. ;) ;)

I have seen virgin motorcycle trails develop whoops where bikes rode under acceleration over a b-ush. Eventually a depression would get churned out on both sides and roost is blown away or water settles in it and mud would be removed with more traffic.

Result -- a full grown Mother Whoop :whiner: in a couple of seasons.
 

whyzee

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#12
Ok, I took this question to my 9 year old son (very smart kid) so this is what I get. ... "Well, woops start by doing something wrong, like scraping mom's car while pushing the bike out of the garage, or pitching an inside fastball and hitting the batter on the elbow, after woops usually you say sorry" ... There we have it.
 

BEEF706

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#13
I knew I came to the right place, a great mixture of science and metaphysics. I am leaning towards a combination of Satan and spring theory, I think it is far too hot down here for the whoop gnomes to survive. It has been so long since we had any rain that the whoops are getting monstrous. So the combination of long travel suspension, slight variations in soil consistancy and a little evil mojo create these bad boys. A sincere thanks for the input so far. :)
 

KiwiBird

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#15
Because most suspension can't tell if the wheel is moving up or the frame is moving down damping must be a compromise. Consequently as we gas and brake the wheel is moving up and down even if there are no bumps.

Say we gas it out of a turn - we make one fairly deep hole and then a smaller one after it and maybe another after that even smaller - drive force makes a little bit down and roost makes it a little upward. As another bikes hits our holes it deepens/heightens them slightly until we have a whoop or series of them.

The whoop depth is mostly determined by the suspension travel - small whoopps come from short travel, large ones from long travel. The more riding on them, the bigger they get.

Distance between whoops seems to be influenced by travel, wheelbase and weight - not so much by those factors directly but by the influence they have on damping. Baja race car whoops are generally bigger and spaced further apart.