Deep rim aero wheels in crosswinds and rain

KeithG

I stood myself a wheel upgrade to 30mm deep aero rims (Halo Mercurys): really quite an impressive difference from my 32 spoke Open Pros, though the ride is harsh on rough roads. I used them on the Etape Caledonia and I'm sure they gave me a big speed advantage as my average speed was way up from the usual (maybe 2 mph difference) tho I appreciate there may be other factors involved.
Anyway, my questions are
1 crosswinds don't seem to make a lot of difference, which is a bit contrary to my understanding, is this everyone else's experience?
2 the rims filled up with water. This kind of negates the advantage of ultralight wheels! Is this usual? It was a VERY wet day.

PhilthyPhil

I have a mate who has Zipp 404s on a Cerv‚lo Soloist and I watched him get blown off the road the other day by the draft from an overtaking lorry so I would certainly say that crosswinds do make a difference. I borrowed them once and even though it wasn't a particularly windy day I could really feel myself getting blown about when I came to junctions and gaps in hedges etc.

method

Although deeper than your Open Pros, 30mm isn't really considered that deep these days. You will notice the wind on 50mm plus, especially when it gusts.

richardjallen

I read an aerodynamics test on rims ranging from standard 21mm, 30mm (shamals at the time) and 50mm and the 30mm rims had almost equal aero properties to the deep sections but the paper acknowledged their stability in cross winds.

simmers

KeithG - would be interested to hear more about your experience of the Halo Mercurys, am considering them myself. They seem to be good value, reasonable quality as far as I can tell, lightweight and as aero as a fairly standard aluminium wheelset gets.

What is the hub quality like? Is the rear quiet like Shimano or noisy like Campag?! Do you have the 16/24 spoke set? You describe the ride quality as harsh, could you expand on that, what tyres are you running? Slightly worried about them filling with water!!

http://www.halorims.com/HaloNew/mercury-wheels.html

monty_dogcp

I've got some 30mm Campag Atlanta rims which I use on my fixed gear TT bike and have never experienced any problems - I'm not heavy either. Similarly, I have some 46mm Ambrosio carbon rims which again have never given me any cause for concern - but I use them for road racing and so don't encounter the slipstream from passing HGVs.

KeithG

Simmers
I have the 16/24 spoke set and they are amazingly light. I am new to performance wheels so I don't have the experience to amke a comparison except on listed weights of the various wheelsets and they do well compared to comparitively priced Ksyriums.
Yes the hubs are noisy. I usually run Campag chorus hubs and they are as noisy as those but with a higher pitch. Personally, it doesn't bother me.
It does seem to transmit road buzz more but then it's s stiffer wheel and it's therefore faster so to transmit all your pedal torque into forward motion, I guess.
I wonder if the water filling thing is because there's so much hollow space in the rim. They do almost empty out on long downhill sections and it was a very wet day with flooded roads so this may not be common. I just wondered if anyone else had experienced this.

schlepcycling

For what it's worth, I have a pair of HED Jet V60s (60mm rim depth) which I have found are affected by crosswinds. As for the filling with water thing, looking at my V60s they are a carbon fairing bonded to an aluminium rim so they have full length spokes between the hub and the rim so there are holes in the carbon fairing for the spokes to pass through, if I rode through a puddle that was deep enough then I suppose water would enter via these holes and fill the void in the carbon fairing. I must admit it had never occurred to me...I will certainly avoid puddles from now on.


665 The Neighbour of the Beast

monty_dogcp

Mavic Carbon Cosmics are notorious for filling up with water too - anything where the spoke passes through the outer rim and is only seated on the inside is going to be a problem

SDP

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Monty Dog</i>

Mavic Carbon Cosmics are notorious for filling up with water too - anything where the spoke passes through the outer rim and is only seated on the inside is going to be a problem
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">

lean against a chair or similar near a radiator along with wet helmet & shoes ....they do dry out ok..

i rode my cosmic elites along southsea prom on whit bank holiday & whilst i wouldnt call them deep ..i could fell it & i aint a little fella...wife was on niobiums... [:(] i was not popular for our choice of wheels in a gale !

www.mjsracing.net