Front Semi aero vs Rear Semi aero wheels??

Hi guys,I had a question and would like'd to ask.Sometimes in races,I saw people using front 50mm deep wheels but rear was a normal 24mm alloy wheels and some was using it oppositely.How much different of benefits will it get by doing any of above and which is better(aerodynamic)??And how much effect will it lose compared to both 50mm deep wheels??Thx.

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I've found Reynolds Wrap on my spoked wheels to get the same aerodynamic benefit of any disc wheel in my Xero.Plus,I can peel it off and bake a potato after my ride. Can't do that with Zipp's. That's value add.

The best thing to do would be have a rim in back that's deeper than the front. It's pretty common, for example, to see a bike with a Zipp 404 on the front and an 808 on the rear. There are a few reasons for this:

1. A more shallow front wheel is easier to control in strong crosswinds. That's why you don't see disc wheels on the front, except on some track bikes.
2. A lot of or all of the rear wheel is in the turbulent shadow of the frame and rider. A deeper rim is more likely to encounter less turbulent air flow or better control/manage turbulent air flow.
3. A deeper rim on the rear doesn't complicate bike handling/steering as much a deeper rim on the front.

With regard to aero wheels, keep in mind that the best aero wheels only add about 0.4 mph at 25 mph. Don't expect aero wheels to perform performance miracles. With that said, aero wheels can make a significant benefit on long and/or fast descents, and aero wheels are now available at some pretty damned reasonable prices.

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I agree on the crosswind matter.

Keep in mind that in some particular no-wind TT somebody uses front disc (for instance Bruseghin in the TT national italian championship 2005), but he's a pro' and he has all the materials he wants

if you see somebody with low profile on the rear wheel, well, perhaps he punctured and he had only that wheel to be use as a replacement...

Hahahaha.....Thx alot guys.I think i had the answer for my question in mind .

1 more question.Is the effect of crosswind deadly if using both 80mm wheels in the peloton of road race/training with road bike??I heard my clubmates said you might be flying off from the bike if fail to handle the crosswind when heavy vehicle passing by during training.Is that seriously true??Can you guys please explain how deadly it is??Sorry for being annoying because I am truly curious about it .

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I've found Reynolds Wrap on my spoked wheels to get the same aerodynamic benefit of any disc wheel in my Xero.Plus,I can peel it off and bake a potato after my ride. Can't do that with Zipp's. That's value add.

Not necessarily. How much influence crosswinds have on you on the bike is a function of rim height to a significant extent, but it is also a function of how much you weigh and how nervous or relaxed you are at controlling your bike in crosswinds....or when a big truck passes by. Personal experience is the only way to say for sure whether it'll work or not. When I wuz' riding Reynolds Stratus DVs (46 mm rim), I was out on 'em on more than a couple red flag days here in Tucson. On one ride, the wind was gusting between 30 and nearly 50 mph. I didn't find it deadly or even worrisome. The blowing sand and dust did suck, though.

I'm not sure why you'd want to run two 808s. 404s are great in aero terms and provide less worry in windy conditions and tight quarters.

__________________
Sex is horrid
Pain is Fun
I cut my fingers off
One by one

Oh.....80mm wheels seems more striking when spinning with a bigger sticker on it .Now I am using a Dura-Ace C50 and I didnt feel any crosswind effect on the road which means it is much better than I imagine how bad it is after listening to my clubmates which using the same wheels as you do .

__________________
I've found Reynolds Wrap on my spoked wheels to get the same aerodynamic benefit of any disc wheel in my Xero.Plus,I can peel it off and bake a potato after my ride. Can't do that with Zipp's. That's value add.

Have you got the new 50mm clincher with the alu braking surface, or the tooobulars? How are they? Are they stiff as bricks?

Yes I got em.The clinchers.Actually I am about 117lbs so I cant really tell you how stiff they are because so far doesnt have any wheels that is doesnt stiff for me .They are too calm in high speed.Very nice in accelerating.

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I've found Reynolds Wrap on my spoked wheels to get the same aerodynamic benefit of any disc wheel in my Xero.Plus,I can peel it off and bake a potato after my ride. Can't do that with Zipp's. That's value add.

Nice. There's not many of them of them around, so it's probably a fair effort to even find some. I don't think there's any in Australia at all.

Since our dollar dropped recently (well, more like plummetted), they've gone up from $2000 to $2500

Aww....$2000 to $2500 is quite alot.And yes this wheels actually costed me a big big bomb but it is a pair of very nice wheels.Hope you can get yours soon

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I've found Reynolds Wrap on my spoked wheels to get the same aerodynamic benefit of any disc wheel in my Xero.Plus,I can peel it off and bake a potato after my ride. Can't do that with Zipp's. That's value add.

eh, i might wait a while until every Shimano dealer has them, which will hopefully drop the price a bit as they start competing with one another.