senbot

I'm looking at building up a set of wheels with 36 hole 105 hubs, DT competition spokes, and Velocity Aerohead and Aerohead OC rims. All told, it will cost about $300-350 Canadian and weigh 1771 g (according to the DT spoke calculator). At about the same weight (1765 g), and five times the price, there are Mavic Cosmic Carbone SLs. What justifies the price difference?

GatorFL

Carbones are heavy for the price. However, you're paying for aerodynamics, which in most cases is more important than weight.

Homebrew01

Hubs with low rolling resistance ?

cyclingvirtual

Well it depends what do you want them for, at that weight and 36 spokes, they would not be competitive for most racing. Not familiar with the rims, but they would make a bullet proof pair of training wheels.

Why do you want 36 spokes.?

senbot

Do 105 hubs have high rolling resistance? Which level of Shimano would be low rolling resistance?

grolby

You're not going to get hubs with lower rolling resistance than Shimano or Campy, and it wouldn't matter if you did.

Cyclingvirtual is incorrect about your planned build being "not competitive for most racing." Wheels simply aren't going to mean a damn thing in most mass-start race situations, particularly in low-level amateur (USAC) races. A wheelset between 1700 and 1800 grams is perfectly fine and probably represents the best bang-for-buck you can get for wheels. With wheels, you have a trade-off to make, as you do with many things. With wheels, it is: light, aero, inexpensive - pick two. 1700 grams for a deep-section wheelset isn't at all uncommon, and the aero benefit is definitely worth more than light weight. For what it's worth, I've been racing with a 32-spoke Aerohead/105/Wheelsmith wheelset, and I'm doing quite well, thank you (~1700 grams).

You might consider 32 spokes. You'll drop some weight, and the strength problems you'll have with that wheel will have a lot more to do with the Aerohead, which is kind of wimpy. Going with the OC rear should ensure a nice strong rear wheel, though, so a well-built wheelset will be plenty durable. Just don't crash it!

cyclingvirtual

dont worry about hub rolling resistance, it is negigable.
If you want fast wheels, then reduce spoke count, and use aero rims.

Aero rims are stronger and lets you get away with less spokes.

senbot

I mostly want 36 spokes to lace them 3 leading 3 trailing. I don't race or anything... I was just surprised that the weight on super-fancy wheels was similar to the very basic wheels that I am building. I had always thought that weight of wheels was the big thing. Why would wheels with a similar weight and fewer spokes be more competitive?

thanks for all the replies!

cyclingvirtual

Maybe i will rephrase my "not competitive" quote. A good rider with 36 spoke wheels will usually beat a lesser rider with the best most expensive wheels. But IMO, a set of 36 spoke wheels, even in massed start racing will be putting yourself at a disadvantage. I used to think all these areo wheels were of little benefit in a RR, until i got some myself.

grolby

Because aerodynamics are far more important in most situations than is light weight. Zipp 404's are not fast wheels because they are light (the rim is heavier than the Velocity Aerohead), they are fast because they are aero. Same with other deep-section rims. Should that matter to you? Probably not. I happen to like light wheels, but that's probably because it's much easier to build a light set of wheels without spending a fortune than it is to build an aero set of wheels, unless you don't mind a 2000 gram aero wheelset. Some won't. It's all about priorities.

halfspeed

Way too general. Aero rims =may= be stronger than a light box section rim depending upon the strength/weight compromises made on each. It's easier to make a light rim with a box section but it's easier to make a strong rim with an aero section. Fewer spokes are often necessitated by an aero rim to keep the wheel weight competitive with a wheel built on a box section. But fewer spokes may reduce the durability and maintainability of the wheel even though the rim may be stronger.

It's all about how the builder balances the compromises between strength, weight, aerodynamics and cost.

tekhna

I think weight is the least important factor in a wheel, beyond a certain point. I don't want a 2 kg wheelset, but I'd rather have many 1800 gram wheelsets than many much lighter ones.

patentcad

Essentially correct, that only point I would add is that you can never get enough help if you suck @ this sport. My Zipp 404 tubulars do make hanging on to much faster guys noticeably easier aka possible for idiots like me. There are times when I'm on the rivet so bad that I'm convinced with non aero wheels (or heavier wheels on climbs) the elastic might actually snap. Do $2000 Zipps confer an advantage? A small advantage perhaps. But sometimes, in race situations, that can the straw that breaks the camel's back - or saves your day. Not everybody can drop $1100-$2K on wheels (I picked my Zipp tubie 404s up on eBay for $1100 one year old), and if that's your situation, follow grolby's guidelines, STFU and race your bike.

Should you want to upgrade some day, I can only tell you that I've never met a weekend racer Zipp owner that felt his wheels weren't worth the money. Do your own informal survey as you race and start saving...

grolby

pcad, you may rest assured that if I am still racing when I have the disposable income (and sheer will) to drop $2K on wheels, that I will pick up a set of whatever the Fast Wheels Du Jour happen to be. I have no doubt that they can make that difference. Even if it's placebo - and I'm not saying it is - that matters. For now, the top priority is a race bike with integrated shifting that weighs less than 23 lbs.

foresthill

Keep in mind that there are much lighter "super fancy" aero carbon wheels available than the Cosmic Carbones. At least in the clincher world. For example:

Reynolds Assault (46mm) - 1565g - $1295
Reynolds Attack (32mm) - 1485g - $1195

Tho i guess reynolds makes even fancer versions of that wheel with DTSwiss hubs instead of their own, tho they're twice the cost.

Personally, I ride wheels that aren't super aero, but are very light (1295g), and I like the way they ride a lot.

patentcad

I can't disagree with this. You should be able to get a 17-18lb racing bike for sub $2K new, less used. Good luck, hope you can find something you can afford and use.

We ramble on about schwag here, but that's the last thing cycling is about. Often the schwag just gets in the way. Keep it simple and enjoy the ride.

shakeyourbotty

I heard this on the Zipp or Rpl;f Prima website, can't remember though:

Pros care about stiffness first, then aero. Only then is making a light wheel important.

My thinking is instead of losing 6 grams on carbon bottle cages, you should lose 5 off the waist. Once you look like rasmussen or boonen can you excuse buying all Carbon components.

To be fair though, the only places worth weight saving are wheels and frame. Anywhere else and you look like a FRED, or get accused of needless bike shwag.

asgelle

Help me out here. Why are these exclusive? While you're losing 5 off the waist, I've lost 11 off the waist and bottle cages. (You also might explain why weight on the frame is different from weight on the components.)

Beaker

Are you aware that 5 millilitres of water in your bottle is 5 grams?

ridethecliche

I built up my 84 trek for like 700-800 bucks and it's 21lbs.

If I spent 200ish more, I could get it down to 18-19 lbs. That's vintage steel for ya!

waterrockets 

105 hubs will WHOOP UP on Mavic hubs for rolling resistance. It doesn't get any better than loose ball hubs.

vic32amg

stickers. the bigger the better.