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Shape of jumps - wh...
 

[Closed] Shape of jumps - what's more important

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[#534899]

Calling all you trails diggers...

Just been riding a track that has been built near me and it needs some tweaking to get it running nice but is gonna be good once it is sorted.

I've just had a long discussion with someone down there which has led me to ask this....

What's more important on a double or triple or a roller, is it the size of the transition, the shape or the overall height of the jump?

Bascially if the jump is small (1m high) but not shaped that well so pumping over it is hard, can shaping it to make it pump better be more productive than not changing the shape but making the jump higher or the transistion longer (meaning keeping the jump the same height but removing earth to start the transision earlier and make it longer but the overall height stays the same)?

Does that make sense?


 
Posted : 07/05/2009 7:03 pm
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nope
I'd build it to be jumped rather than pumped


 
Posted : 07/05/2009 7:11 pm
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the size of the tranny will dictate the distance. The shape is important. A big kicker will give height but then you need more speed to get the distance.


 
Posted : 07/05/2009 7:14 pm
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Not looking at jumping them for distance more pumping over to gain speed.


 
Posted : 07/05/2009 7:16 pm
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Play with the shape then. So much fun to be had.....


 
Posted : 07/05/2009 7:30 pm
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Fun - Thats what I'm thinking.

The option I'm being told has to be taken is move about 20tons of earth to make them about 6 inches higher.


 
Posted : 07/05/2009 7:40 pm
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20 tonnes!

How big are they? Got a photo?


 
Posted : 07/05/2009 7:42 pm
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Here you are... they want to move the earth between the jumps on the two middle sections.

[img] [/img]

[url= http://www.flickr.com/photos/bushwacked/sets/72157617687804033/ ]Pics in more detail[/url]


 
Posted : 07/05/2009 7:55 pm
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Looking good! where is that? I want to lpay...... 8)


 
Posted : 07/05/2009 8:08 pm
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Just outside Cheltenham.

Went for a spin on it earlier, bit rough in places and the jumps need shaping (hence this post) but its going to be awesome!


 
Posted : 07/05/2009 8:11 pm
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Not sure whether I understan but I could probably help you if i did.

You have some rollers that are a metre high and you want to make them easier to pump over?


 
Posted : 07/05/2009 8:25 pm
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If its the rollers slightly to the right of the center then they look an awful shape for pumping over.

Theres no dip in the middle to be pumping through, If you wanted to gain speed off them id imagine it would be better to double them up.

To make them easier to pump through you need to be moving the humps apart and having a nice smooth dip in the middle


 
Posted : 07/05/2009 8:28 pm