Why trailing fenders work

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LightninBoy
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Why trailing fenders work

Post by LightninBoy » Fri Jan 08, 2016 12:15 pm

Here's a short video I took at the Minneapolis Science Museum. This exhibit was one of the inspirations for the X3 fender design, a design which is now dominating all the wide wheel league races (where fenders are allowed).

Although I haven't tried it to be sure, this does suggest that just a trailing fender is better than no fender at all. I think that is something to consider if you like to run a long wheelbases in scouts for extra stability that leaves no room for a front fender.




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whodathunkit
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Re: Why trailing fenders work

Post by whodathunkit » Fri Jan 08, 2016 9:26 pm

Cool video.
Thanks for sharing it LightninBoy.


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bracketracer
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Re: Why trailing fenders work

Post by bracketracer » Sat Jan 09, 2016 12:00 am

LightninBoy wrote: Although I haven't tried it to be sure, this does suggest that just a trailing fender is better than no fender at all. I think that is something to consider if you like to run a long wheelbases in scouts for extra stability that leaves no room for a front fender.

Definitely an idea worth testing! One concern I have is that the display in the video is basically a thick 2D representation, it doesn't allow for lateral flow? Air striking an unprotected wheel tread moves to the side quite a bit. Which I know you know, since the LB-style fenders greatly reduce lateral flow.



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ciodude
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Re: Why trailing fenders work

Post by ciodude » Mon Feb 06, 2017 8:42 am

Does a racer even get up to a speed where this is a real issue?



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Vitamin K
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Re: Why trailing fenders work

Post by Vitamin K » Mon Feb 06, 2017 9:40 am

ciodude wrote:Does a racer even get up to a speed where this is a real issue?
Yeah, league performance and track tests definitely show improvements from fenders.



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Re: Why trailing fenders work

Post by chromegsx » Mon Feb 06, 2017 12:36 pm

ciodude wrote:Does a racer even get up to a speed where this is a real issue?
Typically the answer to this will depend on how good the rest of your build is. More important things come first. alignment, weight placement, wheel prep, etc. Once one gets those things near perfect, the aero factor should be considered. But the short answer to your questions is yes. Aero can and does play a factor. Even more so as you move the COM back and making the front end lighter.



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davet
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Re: Why trailing fenders work

Post by davet » Fri Feb 10, 2017 9:04 am

That video is why we built our car as we did. Thanks.



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