wacomme

Thanks. Just wondering because I often see carbon wheelsets with 20(18)/24(20) spoke combinations.

valleycyclist

Deeper rims are usually stronger and can handle fewer spokes better. The advantage of carbon rims is that they can get deep without adding too much weight. Something else to consider is to use 20 spokes on the rear, but use DT Competition or Sapim Race spokes instead of CX-Rays.

FYI, I used XR-270 rims for a while on test wheels with 20f/24r spokes. I used Sapim Laser spokes on the front and rear non-drive side and Wheelsmith DB-14 spokes on the rear drive side. I weigh about 145 and experienced no issues with them, and that was with Novatec hubs which do not have the same flange geometry as Alchemy hubs. So you will definitely be fine with 20f/24r spokes, and you should not have anything to worry about if you go with 24 rear spokes.

wacomme

What's the aero advantage between 28 and 24 or fewer spokes? Like the weight, is the aero advantage of four fewer spokes negligible?

valleycyclist

It makes a bigger difference on the front wheel which is helps justify using 20 spokes on the front. I do not think the extra four spokes have as much of a negative difference on the rear wheel.

ilovecycling

Who says you can't get a nice carbon tubular wheelset for under $1k?

https://www.novemberbicycles.com/

Their RFSW 38 tubular is $685 (pre-order to receive wheels in February). The weight is 1270 grams for the 20/24 spoke build and 1320 grams for the 24/28 SOB ("side of beef") build. At 160 pounds you shouldn't have durability issues with either, but you could go with the SOB build if you want to play it safe. Looks like it certainly meets all your criteria at well under $1k. Also, at a rim depth of 38mm you might get a bit of "aero advantage" for race day. Well, I'll just be honest with you and say that you probably won't, but they'll definitely look proper on a race bike for race day. Tubulars are also the way to go for racing.

As for November Bicycles as a company, the owners are top notch guys and frequent these boards often to answer questions about their wheels and framesets. From what it looks like, they are very helpful and honest guys that will back up their product if something goes wrong.

jamesdak 

I looked at these also when considering my purchase of climbing wheels. The owner actually emailed me and advised me not to go with them due to concerns of heat build up on long descents. Very straight up and honest company in my book as they could have easily just sold me the wheels. IIRC my initial contact with them was about wheels for the LOTOJA event a 209 mile one day race with lots and lots of climbing and descending. So by long descents I am talking miles at high speed not 1/2 mile down some hill.

ilovecycling

I thought about this as well when making the suggestion, but after my first real climbing ride last weekend (5k feet @ 5% grade) I realized that I really didn't ride the brakes at all. The only time I slowed down on the descents was when I was going faster than a car or another cyclist and had to check my speed when approaching them from behind.

Also, this should only be a real concern if you are set on clinchers due to the side wall of the rim warping and the tire bead unseating. If you go with tubulars heat build-up shouldn't be as dangerous. Then again, I'm not sure what the consequences are of heat on the glue that bonds the tire to the rim.

If heat build-up is a concern of yours then carbon rims from any manufacturer should probably be taken off your short list. Aluminum will always work better for dissipating heat.

wacomme

Living in Colorado and riding a lot of mountain roads, heat build-up is a concern for me. Thus, if I decide to go the carbon route for wheels they'll most likely be tubulars. And while I trained and raced on tubulars many years ago, I'm not sure if I want to go down this route again.

ericm979

The heat problem with carbon wheels is more with clinchers than with tubulars. High speeds are not so much of a problem; it's steep descents with tight corners or other features (i.e. traffic) that require a lot of braking, along with low speeds that remove less of the heat from the rims.

It's a problem for clinchers because of the U shaped rim in cross section. The legs of the 'U' make a long path for heat to conduct away from the brake tracks. Worse, the tube is forcing the tire to spread the 'U' apart with 110 psi. So you have hot carbon fiber with a lot of force on it. When the carbon fiber gets too hot the epoxy softens and the 'U' spreads open.

Some newer clincher rims from the major carbon rim manufacturers either use higher temperature epoxy (it's actually a harder problem than just dialing up the epoxy supplier, I am simplifying) or add heat resistant material to the brake tracks. They also use brake pads designed to not heat the rim as much for a given amount of friction.

Safely using carbon clinchers depends on your descending skill (confident descenders brake less), the terrain you're riding on, your weight, traffic etc., and the specific rim/pad combination you're using.

This is a good review of some of the major carbon clinchers: https://www.velonews-digital.com/velonews/201103?pg=74

I think that current carbon clinchers are a waste for training. They're not lighter than aluminum wheels, just more aero. While that can be of a small use in a race, in training it's not important. If you're on your own having more aero equipment is no value at all, and if you're in a group being less aero will just encourage you to do a better job of drafting, which is something you should be practicing anyhow.

The drawbacks- brake heat problems on steep technical descents, and the expense of replacing a rim- far outweigh the "advantages" for training. OTOH I use them for races including ones with a lot of climbing and descending. Just not ones with steep technical descents, which are rare in US amateur races as they cause massive carnage.

ColinL

I think you've got that reversed. Both tubular and clincher carbon rims can fail from overheat during descents.

BEFORE that failure, tubulars can come unglued. Clinchers will not come unseated from heat alone.

The Smokester

Stans Alpha 340 rims, Chris King R45 hubs, 20/24 DT Swiss Aerolite spokes, Alloy nipples. Should come in 1200+ grams. About $950.

wacomme

Compared to the XR-270 rims, how sturdy and rugged are Stan's Alpha 340 rims? And how do the KC hubs compare to the Alchemy hubs?

ilovecycling

That's exactly why I said I wasn't sure what the consequences of heat on tubular glue were. I haven't experienced any failures of this type myself, so what I said is just what I understood to be the case. Maybe I'm wrong though.

However, in every written article I've ever read regarding carbon fiber rims and heat, the first thing they talk about is carbon clincher failures due to the outward pressure against a soft/warped brake track . They never mention carbon tubular failures, but again I suspect that this could be an issue too.

So is that fact, then? Tubular glue will heat up and become tacky before a clincher tire bead pops off the rim? I'm not doubting it, just want to know for certain which is more likely.

jamesdak 

Too be honest I don't ride the brakes either, when I have a choice. But lots of variables come into play that dictate how fast I can descend. Gusting winds can make things real hazardous and will sometimes force me to ride the brake and hold the speed down in the 30s even though I may normally do the route at around 50 mph. Also if I haven't prerun a route I have to take it easy instead of going all out. Nothing like coming into a sharp curve at 40+ mph just to see the loose gravel, broken pavement, etc ahead. I guess my point is that I am a speed freak and love going fast. But often the conditions prevent me from riding like I'd like.

af2nr

Have you considered any Easton wheels? There are various models available and with a little looking around many of those can be had for less than your spending limit. I have had the EA90 SLX wheels for almost two years now, all but about 6 weeks of that in WV where the roads are pretty rough. I have only used them here in CO for a few weeks but the conditions seem much better overall here so I feel they'll still do well. I am 6' and 175 lbs and have had ZERO issues in my time on them and they have been a everyday wheel. If you don't care about some of the upgrades you can even get a set a couple years old from Performance for less than $500.

I also have tested the Shimano C24's and like them and would really look hard at them if I were looking for another clincher set. I have yet to take the carbon plunge, initially because of the roads in WV and now because I know that I'm not ready to have to learn the ups and downs here on a wheel that may or may not be ideal for me and my riding style. At this point I enjoy the long climbs more than the long descents here, that will get better as I feel my way around but for now I am over cautious. I'm used to much shorter, and for the most part less curvy, descents than what is here.

wacomme

Funny you mention Easton wheels. Recently I borrowed a friend's Easton EC90 SL TT tubular carbon wheels. I absolutely loved the smooth ride and the lightness. While I enjoyed riding the wheels at speed, and my mind told me aero helped at speed, what I really liked about the wheels was the lightness - quick acceleration and nimbleness. So while I'm not ruling out carbon wheels, though I am concerned about long mountain descents on carbon clinchers (don't know if I want to go tubular; if the wheels were just for racing then I'd be fine with tubulars, but I want to use my "nice" wheels for good weather training too), carbon isn't a necessity - light and stiff wheels are a priority.

I'm also not a great descender. I much prefer riding up than riding down. So while my descending technique can be improved, I'm currently using my brakes on descents more than I should be using them - a knock against buying carbon clinchers.

wacomme

Besides looking locally, who building a nice set of wheels using the following items:

Kinlin XR270 Rims: 880 grams -
Alchemy ELF/ORC Hubset: 289 grams
Sapim CXray Spokes (20/28): 230 grams

ColinL

Just noticed this was never answered.

Chris King started with MTB hubs. The R45 is a dedicated road hub that has a lot of features that made the MTB hubs popular. Full review here: https://road.cc/content/review/20922-chris-king-r45-hubs

Regarding what that proprietary rear hub sounds like: https://www.youtube.com/watch?v=Z8RSxmszAcg


The Stan's Alpha rim has features that are optimized for road tubeless use, but it can use a tube and standard clincher tires. It is lighter than most rims because of this design. You can buy the exact combination Smokester posted on ebay. Stan's full wheels come with American Classic hubs instead: https://www.competitivecyclist.com/pr...257.622.0.html

Anyway, hope this helps. I would buy the Stan's wheel in a heartbeat for mountain use, but as I posted previously in this thread that means you're committing to Hutchinson Atom or Fusion 3 tubeless tires for optimal use. I'm ok with that.

SteveM

https://www.zencyclery.com/road-2/siddartha.html

Also what about substituting Velocity A23 rims(@852grams)

valygrl

Call Vecchio's in Boulder, they can quote you that, and maybe recommend something even better.

The like the Velocity rims more than the Kinlin ones - and having had a pair of XR270s and gotten a defective rim, I wouldn't seek that rim out if you are building up a wheel. YMMV, my $0.02, etc etc.

wacomme

How do the American Classic hubs compare to the Alchemy hubs? Also, how do the Stan's wheels compare to the XR270's?

DScott

The new FLO wheels are intriguing. Carbon fairing/alum rims, reasonably light and well-priced. IIRC they run about 1500 g/set. I like the alum rim choice for just the kind of riding you're talking about, and the aero-ness may help a bit on the flats to the ride and the descents.

Discussed here: https://www.bikeforums.net/showthread...-negative-drag

triumph.1

What about Boyd? They have a carbon 24mm tubular that looks decent for 800 a set. They also have a 38mm for the same price in tubular and clincher. I haven't used them, but haven't read anything bad about them either. I am thinking about a set as a backup to the easton 24's I am using.

wacomme

Boyd and similar brand carbon wheels are certainly an option. However, for where I live, I may need to go tubular with the carbon option. I'm not sure if I want to go the tubular route. I want to stay under 1300 grams. Lightness is more important to me than aero. I can buy some great aluminum rimmed wheels that are clinchers and don't have potential long-descent heating problems, so why would I consider carbon wheels? I'm not opposed to the idea of carbon rims, but I really don't see any advantage for my needs. Fewer spokes? Smoother ride? ???

wacomme

Thanks, but I'd rather stay under 1300 grams/set.