coozer
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posted on 8/3/09 at 10:27 AM |
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Cycle wing aerodynamics
You know them guards with the CSR style hump at the back with a vent to release the air pressure between tyre and cycle wing? You know the ones I mean
right?
Any handy peeps ever thought of producing add on ones for normal plain round guards?
Know where there are some already or pictures of said items?
Ta,
Steve
[Edited on 8/3/09 by coozer]
1972 V8 Jago
1980 Z750
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omega0684
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posted on 8/3/09 at 11:08 AM |
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could you not just cut some slits in the back of the mud guard?
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smart51
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posted on 8/3/09 at 12:36 PM |
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The hump in the back helps brake up the air flow over the top making it less like a wing, even without holes.
Caterham do a nice line in them I believe. I've bought stuff from their parts website and over the phone, no questions asked.
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nitram38
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posted on 8/3/09 at 12:41 PM |
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Carbon Mods do them a lot cheaper than catering
van.............here
[Edited on 8/3/2009 by nitram38]
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andrew.carwithen
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posted on 8/3/09 at 12:54 PM |
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Carbonmods do them in C/F but at £200 a pair I suspect these are not what you're looking for. http://www.carbonmods.co.uk
As regards fibreglass, The nearest I could find were some vented ones on ebay (but they don't have the hump and are still over £100 a pair.)
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Triton
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posted on 8/3/09 at 01:15 PM |
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Blimey £200 a pair.... So if someone was to do them in woven cloth which makes them the same weight as cf and just as flexible there could be some
interest?...I already do my standard wings in cloth.
[Edited on 8/3/09 by Triton]
My Daughter has taken over production of the damn fine Triton race seats and her contact email is emmatrs@live.co.uk.
www.tritonraceseats.com
www.hairyhedgehog.com
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RK
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posted on 8/3/09 at 02:08 PM |
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Say Mr. Mark, are you going to Detling?
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A1
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posted on 8/3/09 at 02:11 PM |
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i was thinking of doing some nice big louvres in the rear section...
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nitram38
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posted on 8/3/09 at 02:52 PM |
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quote: Originally posted by Triton
Blimey £200 a pair.... So if someone was to do them in woven cloth which makes them the same weight as cf and just as flexible there could be some
interest?...I already do my standard wongs in cloth.
Too late, I have two pairs on the MotaLeira
And they aren't flexible, but they are very thin and light.
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james h
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posted on 8/3/09 at 04:06 PM |
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quote: Originally posted by Triton
Blimey £200 a pair.... So if someone was to do them in woven cloth which makes them the same weight as cf and just as flexible there could be some
interest?...I already do my standard wongs in cloth.
Yes please!! I think they should be quite long at the front and back as well as the hump and vents... But then again I am no aero expert.
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Triton
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posted on 8/3/09 at 05:08 PM |
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Well the light weight wings I make almost twist in half and no cracky cracky gel coat either....hillclimbers like 'em
My Daughter has taken over production of the damn fine Triton race seats and her contact email is emmatrs@live.co.uk.
www.tritonraceseats.com
www.hairyhedgehog.com
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Triton
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posted on 8/3/09 at 05:19 PM |
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quote: Originally posted by RK
Say Mr. Mark, are you going to Detling?
Hi Rich,
I can't make the show to have a stand there but if I get a chance and I need a day off I may just go up but it's a long trek from wet
'n windy Cornwall.
Mark
My Daughter has taken over production of the damn fine Triton race seats and her contact email is emmatrs@live.co.uk.
www.tritonraceseats.com
www.hairyhedgehog.com
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alistairolsen
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posted on 8/3/09 at 08:43 PM |
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Triton, if you could replicate that wing style in GRP cloth I would be very interested
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Triton
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posted on 8/3/09 at 10:19 PM |
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Okey doke it's been added to the list of new bits to do although I have to get Mr G's beast sorted first.
Cheers,
Mark
My Daughter has taken over production of the damn fine Triton race seats and her contact email is emmatrs@live.co.uk.
www.tritonraceseats.com
www.hairyhedgehog.com
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C10CoryM
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posted on 9/3/09 at 11:29 PM |
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So silly question but what exactly is the intent of the wing shape on the cycle fender?
The louvers make sense to me, but the wing does not. I would guess you would do better to follow the LMP cars and run louvers only. Besides, how
much downforce do you think you are going to get through your cycle wing bracket?
"Our watchword evermore shall be: The Maple Leaf Forever!"
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alistairolsen
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posted on 10/3/09 at 01:04 AM |
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its not a question of downforce so much as reducing lift!
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nitram38
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posted on 10/3/09 at 07:37 AM |
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Another way of reducing lift is to bring your wings further forward. Having them look by tilting them further back increases the drag and hence
lift.
This leads to brackets needing to be made stronger and more weight.
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Triton
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posted on 10/3/09 at 10:09 AM |
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Or just fit a full body as a 7 is as aero dynamic as a lego brick with wheels.
My Daughter has taken over production of the damn fine Triton race seats and her contact email is emmatrs@live.co.uk.
www.tritonraceseats.com
www.hairyhedgehog.com
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alistairolsen
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posted on 10/3/09 at 04:29 PM |
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yeah, having them starting more than halfway down the wheel will stop air going under them as much in the first place.
quote: Originally posted by Triton
Or just fit a full body as a 7 is as aero dynamic as a lego brick with wheels.
Depends if you want to reduce Cd for high speed, or just stop it taking off
I dont care if mine will do 130 or 140, I do care if its lifting the nose at 110!
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Triton
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posted on 10/3/09 at 05:30 PM |
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Surely you mean 70mph sir!!! Yes officer honest
My Daughter has taken over production of the damn fine Triton race seats and her contact email is emmatrs@live.co.uk.
www.tritonraceseats.com
www.hairyhedgehog.com
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alistairolsen
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posted on 10/3/09 at 07:26 PM |
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I was of course referring to tuning the handling for trackdays
[Edited on 10/3/09 by alistairolsen]
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C10CoryM
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posted on 11/3/09 at 12:14 AM |
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I still don't see the point of the wing shaped fender . If you are trying to reduce the lift of the fender to reduce drag, doing so by
adding a drag inducing wing doesn't make sense. I suppose youd make less dray with the wing than with the fender opening up though.
Tight fitting fenders that go as far forward/down as possible and louvers to release the air pumped in them from the wheel seems best to me.
I also wonder just how bad the locost aero has to be. The Prowler is 0.4**CoD if I remember right which still sucks, but is better than the 0.7 that
the cats claim. Anyone know the Atoms cod?
I intend to play around with things on my locost once it hits the road. I have a few ideas that I think would drastically improve the aero.
Cheers.
"Our watchword evermore shall be: The Maple Leaf Forever!"
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Rob Palin
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posted on 11/3/09 at 07:41 AM |
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The original wings that were re-styled to later become the CSR-style ones did reduce lift by nearly 70% whilst also reducing drag by a noticeable
amount too. The square rear end was primarily intended for drag reduction and the extension around the front for lift reduction (in conjunction with
the louvres which were subsequently deleted).
They don't reduce the lift by producing any downforce in themselves, just minimising the lift generated, which is largely why they reduce
overall drag, not increase it.
The CD of a 7 is indeed around 0.68-0.76 but the lift coefficients are also +0.2 to +0.3 at the front and 0 to -0.1 at the rear. For a normal
production car you'd aim for less than 0.1 at both ends, but preferably similar values for balance and preferably a slight bias to the front for
increased stability. You don't always get that though.
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