New Wheels

BTW just been following a very interesting thread on WW about aero wheels, and about a recent Tour test where apparently a Mavic Ksyriums SL beat a Reynlods DV 46 for aerodynamics, and now apparently, Zipps own tests show similar results. A tech from Zipp gave some very interesting info, must be treated with a degree of caution of course but here is the main bit :

"Sorry some are having trouble with the data for the Reynolds and the Mavic. I definitely take umbrage with the suggestion that there is any manipulation going on with the data; as I said before, our record with data relative to Tour magazine, BTR, and other independent sources speaks for itself. I realize that when results don't agree with one's expectations it's easy to claim shenanigans with the data but that's absolutely not the case, as should be obvious with some further investigation (the data is out there).

I've previously posted data for the Reynolds on here as well as the Shimano 50mm wheel when it was purely v-shaped in profile as the Reynolds. The difference between those data sets and this is that those were with 21mm tires and this was with 23mm tires. The reason 23mm tires were chosen is based on our surveys of users of this type of rim. That poses a definite handicap to v-shaped wheels as they are much more sensitive to tire width exceeding the width of the rim itself; this is one of the benefits of the toroidal profile. The Reynolds in particular is rather narrow, hence it is such a poor performer in this test; we've shown the superiority of the 202 relative to it previously with a 21mm tire but with the 23mm tire the relative differences between these wheels increase. The Reynolds tests reasonably well with a 19mm tire, but then most every other wheel will see a similar reduction in drag with such a narrow tire; in our case, the difference between a 21mm tire and a 23mm tire on our rims is close enough in certain models that it doesn't even fall outside the resolution of the tunnel itself.

Regarding the Hed data, you'll see a similar trend in their data but at a different magnitude. Again, not knowing the specifics of their tests I cannot comment on why there would be such a difference. As I said before, given the quantities of runs we performed with each of these wheels, I have the utmost confidence anyone can replicate these results within ±10 grams of drag.

The Ksyrium has always been a poor performer in the tunnel but the switch to a 23mm tire leveled the field a bit. Those results were a bit surprising once we began piecing everything together, but sometimes the eyeball wind tunnel doesn't agree with the actual data as closely as one would expect.

[Belated edit] One thing that gets easily lost in all this is when comparing numbers from different tunnels, different days, etc. it's best not to look at raw numbers but rather relative performance; the trends will definitely be the same but the numbers can vary significantly between tunnels even with all else held constant."

I'm sure their toroidal competitors HED will also agree with Zipps study, again hardly surprising, both companies marketing depts would probably turn rusting spokes into a 'must have' aero advanatage

... however it was a Tour test which found similar results test that sparked off the whole debate on that thread. I couldn't give a rats arse about half the tests out there and more so the Tour ones but it did raise some interesting points.

blorg wrote: »

I think that was a Zipp study, which hardly surprising as they are the ones making "toroidal" rims.

I'm somewhat sceptical as most of the peloton are on non-toroidal deep section wheels not made by Zipp. If it really mattered the top guys would be on X Y Z (cf the wide pro takeup of Lightweights in the early 2000s, or was that just superstition.)

blorg wrote: »

I think that was a Zipp study, which hardly surprising as they are the ones making "toroidal" rims.

I'm somewhat sceptical as most of the peloton are on non-toroidal deep section wheels not made by Zipp. If it really mattered the top guys would be on X Y Z (cf the wide pro takeup of Lightweights in the early 2000s, or was that just superstition.)

Uninformed opinion ? Jaysus Blorg, I'm not even at grasshopper stage compared to you !!

blorg wrote: »

I have Zipp 404s myself, have not yet raced on them. But I am skeptical as hell!

In the sort of situation where drag differences are quoted between 23 and 21mm tyres, I will not deny there could be differences but I suspect that these are blown up and would be insignificant in a race.

Just my uninformed opinion.

I know I can hear deep section rims revving up behind me and it is a definite hint to get ready to grab a wheel.

crumliniano wrote: »

Contibutors to this forum seem to fall into two categories
(1) Those who think the Campag spoke pattern is cool and
(2) Those who think it is rank.

I'm sort of half and half, e.g. I think it looks fine at the front. :pac:

abcdggs wrote: »

Is this from concerns over how effective the threading is in power transfer?

No, there is a lot of stuff out there on the supposed technical benefits or lack thereof with a paired spoke spoking pattern (of which the Campy three spoke is a variant) but at root I just think it looks awful. Paired spokes (Trek/Bontrager/Rolf) look better IMHO but spacing the spokes evenly around the rim looks best of all.

Good job my Shamals are in the garage and cant see your comments !

blorg wrote: »

No, there is a lot of stuff out there on the supposed technical benefits or lack thereof with a paired spoke spoking pattern (of which the Campy three spoke is a variant) but at root I just think it looks awful. Paired spokes (Trek/Bontrager/Rolf) look better IMHO but spacing the spokes evenly around the rim looks best of all.

Murph100 wrote: »

THIS is an honest, no BS, explanation of that spoke pattern from a pro wheel builder.

I think the main benefit though is the 2:1 spoke pattern which they also do on Fulcrum wheels but with evenly spaced spokes. I don't think there is any advantage to sticking all the spokes together like that... there are those that argue that you need to over-engineer the rim to keep it straight in the gaps. Also, in the unlikely event of your breaking a spoke you are fecked as the rim will deform massively.

Please advise these or these

The spinergy wheels are available here, price is good.

Budget approx. €800

Well I only know the Mavics, bombproof but a little heavy and erm .. noisy / audible.

Spinergys I honestly haven't a clue.

Just going by your username, are you based in Kerry ? If so, ya might be better off getting a lighter wheelset for the climbs / crap roads / high winds, of which there are plenty crackers for that money.

Wrong link,try this one.

I'd need to rob another bank for the Reynolds.

kerryscoob wrote: »

Kerryman living in Cork, what other wheelset would you recommend in or around that price range to fit on this.

Buy some 7850 C24 CLs, then weigh them for me.

Heheheeeeeeee ... so the Ardennes got a lil' porky over the winter, PHEW ... soo nearly went for them, of course you'll no doubt take great delight knowing that the Am Classic Mag 300s you turned me off still haven't arrived at Epic Cycles ...

However the Shamals are ACE !! ... and best of all the 2009 set weigh less than the 2010 set ( which are more realistically weight quoted ) ... even better... Blorg HATES them

( I know I've just ensured my demise by paired spokes failure near Blorg probably in the ROK or SK )

Lumen wrote: »

Buy some 7850 C24 CLs, then weigh them for me.