A few basic wheel questions....

Everything about building wheels, glueing tubs, etc.
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TimF
Posts: 31
Joined: Wed May 09, 2012 11:18 pm

by TimF

Hey all,

Hope you can put up with some basics :mrgreen:

Would like to check some facts, please correct / add to my list :D !

1. Semi areo is the best bet? I've seen the odd video that states if you're not permanently hill climbing then there are advantages to going with a smaller areo rim. Larger areo rims would be useful for time trial but are overkill for standard riding and heavier.

2. Alloy rims under 450grams are a bad idea and generally not very common. Obviously applies to the more areo ones even more!

3. Carbon rims are 90% efficient braking in the wet after the initial surface water has cleared (i.e. pad has been round the rim once)

4. Clincher rims are the most popular for non racing. You can change tubes if they flat. I'm not seeing much love for tubeless here.

5. 19mm or wider rims are recommended for running larger tires such as 25mm ones. What's the optimum?

6. 25mm tires or larger are becoming standard as they can be run at lower pressures and are more comfortable (probably not true for racing).

7. You must run specialist brake pads for carbon wheels. How quickly do the rims wear out?

8. Chinese carbon rims / wheels on ebay are a bit of pot luck. I'm not clear if people are using these.

Looking at some lightweight wheels, that aren't for racing but should be usable daily. I'm thinking 19mm (or larger) clincher in alloy with some Novatek hubs. Rims maybe kinlin xr31t or H Plus Son Archetype. I'm a light rider and not too worried about wearing them out. I still don't understand what is recommended at the £400 region in rims, carbon or alloy etc. Some options would be appreciated!

Thanks! Tim

alcatraz
Posts: 1295
Joined: Mon Aug 29, 2016 11:19 am

by alcatraz

TimF wrote:
Mon Jan 22, 2018 10:12 pm
Hey all...
I'm not a bike mechanic, just amateur but here is my take.

1.Depends on your average power. If you can average 300w (instead of 200w) then the break even point aero/weight is at quite steep gradients like 9° or something. If you have low power then it's at maybe 5°. Obviously depends on the depth and weight differences of the wheels you are comparing. Very strong riders can see very little benefit of going shallower than a zipp 808 even on 9+° grades. So aero certainly trumps weight at higher speeds. I'm a weight weenie myself and not very strong but wheels did make me go deeper than the rest of my bike would indicate. It's because I figured the wheels are dealing with high velocities up to double the rider/frame does. Aero gains are within reach here.

2. Assuming you mean carbon. More weight keeps your momentum at speed but takes longer to accelerate or carry uphill. With carbon I'd say the problem with light ones is that quality needs to be higher to ensure overheating doesn't occur. Less material means less heat dissipation. My conclusion is if you are a medium/heavier rider and find yourself on light carbon rims on long or steep descents it's a cause for concern. Especially if the rim is a carbon clincher. Stay on alloy rims or disc brakes if you are a heavier descender or concerned.

3.Apart from the most expensive I'd say carbon rims generally have terrible rim braking ability. Coming from alloy the feeling will never be the same. With good calipers and pads you can get a safe ride though and that's whats important, right? Wet + carbon brake surface is something I haven't had any experience with. I'm not excited to find out really. :lol: I'm 60-65kg.It's manageable I think but precautions need to be taken.

4. Tubeless is the future. Either you love it or hate it. I haven't tried but I've read a lot. Problem is with getting the sealant mixture right. Also because pressures are so high in road wheels it is harder to get the same great sealing as with MTB. Clinchers are becoming popular in races as well I suspect, for marginal gains. Tubular used to be popular for it's riding properties but now it's only used because a racer can keep riding for a while after flatting which saves time. From a performance aspect clinchers are favored.

5. Modern rims are 28mm wide at their widest point. Saw once that a good rule of thumb is that the real tire width is 90% of the widest point on the rim. This way you'll get a nice oval shaped cross section with the tire mounted. 23/25mm tires can be mounted here that later expand to real 25-28mm widths (because of wide inner width of rim). Comfort plays a big role in being fast so if the roads are that bad or you are heavy, then you'll be faster on 28 tires even though it's not super aero. Gotta find your balance.

6. Higher pressure narrow tires are still used for perfect road surface time trials maximum aero. Problem is like mentioned above it's a balance. Wide rims are, if shaped properly, still very aero and allows for that nice low rolling resistance at lower pressures which make them fast on normal roads.

7. If the pads are soft the rims last very long. 20.000km. Depends on your weight, braking style, pads, maintenance intervals. I live in a dry place. I just use cork pads and change them often. They wear out quickly but are cheap. The expensive pads are needed for good dry+wet braking performance and they don't last very long. I hear barradine blue works well for allround weather. For wheel warranty you need to use manufacturer recommended pads.

8. I use chinese wheels. No problems other than poor braking (which is not exclusive to chinese carbon). I got a modern manufacturing technology. I'd say the chinese wheels are on par with 5 year old industry leading wheels when it comes to materials and technology. They are catching up but always behind. Resins are becoming more and more heat resistant. For light riders fine. Heavier riders or crazy long descents you might wanna get the most modern technology. Super light weight rims under 350gr I'd also try to get a better brand.

Conclusion. How about two wheelsets. 58mm deep wide carbon clinchers a la zipp 404 style, and one set of alloy shallow climbers. Thats what I got and my alloys are 1300gr and deep carbon 1500gr. The weight difference is negligable and I've found braking sufficient even in the hills (learning curve) so I rarely use the alloys. I'd suggest you to skip them if you are light. But it's really up to everyone to decide for themselves. Many factors like braking style/wet riding/descend grade+distance will affect your decision.

/a

by Weenie


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silvalis
Posts: 472
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Location: Aus

by silvalis

#3
Where did you get "90%" from?
Chasse patate

alcatraz
Posts: 1295
Joined: Mon Aug 29, 2016 11:19 am

by alcatraz

I think I saw it mentioned by someone reading a zipp wheel manual or a reply from zipp regarding a support question. Not sure...

It's probably just a guideline. Possibly one of those that will be antiquated in 10 years time when a new school of thought comes out. :D

/a

crux
Posts: 105
Joined: Wed Oct 26, 2016 2:20 pm
Location: Zurich, Switzerland

by crux

#3 It really depends on the carbon rim... I'm riding all year long here in the rainy & cold switzerland with my Fulcrum Racing Quattro Carbon and the red campy brakepads. They perform so much better in the rain than all my alloy wheels together. On the other hand the braking with my FFWD F6R in the rain is horrible and it's really difficult to slow down. Another point for the carbon wheels in the rain is, that after the braking ther is not much residue from the pads left on the frame, the alloy pads are making half of my frame black
Last edited by crux on Tue Jan 23, 2018 9:10 am, edited 1 time in total.

alcatraz
Posts: 1295
Joined: Mon Aug 29, 2016 11:19 am

by alcatraz

Fulcrum (campagnolo) wheels are really among the best ones out there.

Gotta find a good rim+pad combination. By that I mean really choose both wisely. Not just get any rim and expect to get great performance using the best recommended pads. They won't necessarily match.

/a

crux
Posts: 105
Joined: Wed Oct 26, 2016 2:20 pm
Location: Zurich, Switzerland

by crux

The newer Fulcrum Racing Quattro Carbon models have the same 3Diamond braking surface as the Boras, they're mid high (40mm), wide (outer width 24,2mm), have a good quality and are not that expensive (around 1000 bucks).

sawyer
Posts: 4511
Joined: Fri Dec 15, 2006 7:45 pm
Location: Natovi Landing

by sawyer

crux wrote:
Tue Jan 23, 2018 9:09 am
The newer Fulcrum Racing Quattro Carbon models have the same 3Diamond braking surface as the Boras, they're mid high (40mm), wide (outer width 24,2mm), have a good quality and are not that expensive (around 1000 bucks).
They are nice ... tbh I find their wet braking performance (with campag red pads) to be average for carbon wheels, which is to say not as good as aluminium rims. Commuting on them in the dark through the city in pi55ing rain was a bit scary tbh! :shock:

Still, they are one of the best value wheelsets from the big brands. Not sure if they are better than a smaller brand like Hunt however
----------------------------------------
Stiff, Light, Aero - Pick Three!! :thumbup:

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IrrelevantD
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by IrrelevantD

Going to tackle these one at a time....

1. Semi areo is the best bet? I've seen the odd video that states if you're not permanently hill climbing then there are advantages to going with a smaller areo rim. Larger areo rims would be useful for time trial but are overkill for standard riding and heavier.
Really depends on the situation, but I'd say about 30mm is a good all-around. Aero enough to be a benefit, but not so heavy that you really suffer up a climb. As with all things aero, take speed out of the equation.. the longer you spend with the air providing resistance from the front, the more benefit it will be. Someone going 20mph will benefit more from aero than someone going 30mph over the same course. If you live or ride somewhere that is relatively flat... you could justify 50mm rims.

2. Alloy rims under 450grams are a bad idea and generally not very common. Obviously applies to the more areo ones even more!
Fully built wheel under 450g, maybe a low profile climbing wheel. You will be hard pressed to find an alloy aero rim over 30mm as they start to get too heavy. I'm assuming you meant wheel, not rim.

3. Carbon rims are 90% efficient braking in the wet after the initial surface water has cleared (i.e. pad has been round the rim once)
I'm going to call BS on anyone that say ANY wheel is 90% efficient in braking in the wet, alloy or carbon. Companies like Zipp have made great strides to try to bridge the gap with special coatings and laser etched brake tracks, but there's a reason other companies like HED went so long without releasing a full carbon deep section rim brake wheel. Carbon just doesn't brake as well in the wet as aluminum.

4. Clincher rims are the most popular for non racing. You can change tubes if they flat. I'm not seeing much love for tubeless here.
I LOVE Tubeless and have been running it on road for about 10 years now. Last 3 years or so has really seen a steady increase in compatible rims and good tire choices. It's a little harder initial setup, but when done right it's extremely reliable and rivals the road feel and comfort of high TPI clinchers.

5. 19mm or wider rims are recommended for running larger tires such as 25mm ones. What's the optimum?
I would say 19mm inner if you can find them. My HED Jet+ are I think 20mm inner, 24mm outer. The narrowest rims I still use are 20 or 23mm outer. General thought being these days is you want the width of the rim to match the width of the tire for optimal aero.

6. 25mm tires or larger are becoming standard as they can be run at lower pressures and are more comfortable (probably not true for racing).
While both of those are true, 25mm is also becoming more popular due to lower rolling resistance. I've read articles suggesting that 28mm may actually be the most optimal.

7. You must run specialist brake pads for carbon wheels. How quickly do the rims wear out?
Yes. You must run carbon specific brake pads. I believe that some mfgs actually require that you run THEIR carbon specific brake pads, else you void your warranty. Brake track wear is going to vary by mfg, how much you use the brakes, etc. Needless to say, it will be much quicker if you use regular pads and may lead to premature failure.

8. Chinese carbon rims / wheels on ebay are a bit of pot luck. I'm not clear if people are using these.
It appears that there are lots of people who buy them. I've red reviews from people who absolutely love the, and those that have had them fail. I think you are right in that it's all about luck. I want to say that most of the people who buy them and like them buy direct from the mfg and not on ebay.
TimF wrote:
Mon Jan 22, 2018 10:12 pm

Looking at some lightweight wheels, that aren't for racing but should be usable daily. I'm thinking 19mm (or larger) clincher in alloy with some Novatek hubs. Rims maybe kinlin xr31t or H Plus Son Archetype. I'm a light rider and not too worried about wearing them out. I still don't understand what is recommended at the £400 region in rims, carbon or alloy etc. Some options would be appreciated!
As for suggestions... personally, I love my HEDs, but I don't know what you'd find in that price range. Are you talking £400 for just rims, or fully built wheels?
* There is a 70% chance that what you have just read has a peppering of cynicism or sarcasm and generally should not be taken seriously.
I'll leave it up to you to figure out the other 30%. If you are in any way offended, that's on you.

Multebear
Posts: 1155
Joined: Sat May 02, 2015 10:11 pm

by Multebear

The 8 statements would be too much to comment on in a single topic. Most if not all of them are debated in other topics for several pages each. If I where you, I would focus on the one wheelset, that you need right now, and then just keep reading this forum, reviews and other peoples experiences in general to get more info on your 8 statements.

As for your upcoming wheelset, I've broken down your requirements into this:
TimF wrote:
Mon Jan 22, 2018 10:12 pm


1) lightweight wheels

2) aren't for racing

3) usable daily

4) 19mm (or larger)

5) clincher

6) alloy

7) Novatek hubs.

8 ) not too worried about wearing them out

9) light rider

10) £400 region in rims, carbon or alloy?

Rims maybe kinlin xr31t or H Plus Son Archetype.
First of all you want lightweight wheels, but you mention two rims among the heavier options. You don't mention aero as a preference, and since XR31 are heavy but aero, I'd say they don't fit your requirements. Archetypes are not light and not aero, I'd rule them out for now.

If your budget is 400 GBP for rims only, there's more than enough for chinese carbon from Farsports, which are very good. I own 3 sets, and am very pleased with them. On the other hand, there's no need for carbon if these are meant for daily use. I'd rather save some money on the rims, and spend them on some better hubs.

If you want lightweight, are a light rider and aren't afraid of wearing the rims, I'd look for rims in the sub 420 grams area. Stans ZTR 340, Ryde Pulse Sprint and probably some of the lighter Kinlin offerings come to mind. Either way they'll be less than 150 GBP. This leaves you with 250 GBP to upgrade hubs from novatec. DT 240s hubs are the safe bet. But you could also go all-in and pick some Chris Kings or if you want very light, then aim for Tune. With Tune hubs you'd be able to get a wheelset at around 1.200 grams, which is very very light, and still within your budget.

Spokes and spoke configuration is another topic. But focus on rims and hubs first. We will get to the spokes later on.

bm0p700f
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by bm0p700f

The op had been reading ill informed ramblings. A wheel is a structure that obeys the laws of physics. The laws are not black mysterious magiç.

1) Aero wheels are just fine. If you have a 1500g aero wheelset then why would you not use them all the time.
There is no physical reason why aero wheels won't go up hills just as quickly as shallow rimmed wheels.

I am about to build a 1300g 45mm deep 26mm wide tubeless ready wheelset. Low weight and aero what's not to like.

Also if an extra 300g makes you suffer up a climb I think you may need to calculate how much extra power carrying that extra weight actually entails. Not alot. Aero trumps weight on nearly every ride that normal people do. That's basic physics.

Also the physics quite clearly shows the aero gain works at all speed as what us changed is the CDA and power required to overcome aero drag is directly proportional to CdA. A 2% reduction in CdA overall from aero wheels means a 2% reduction in power required to sustain any speed so one of the above replies us incorrect.

2) alloy rims can weigh less than 450g and be fine. Mavic have one now. So again this statement is based on generalisations.

3) I have no issues with braking on carbon rims in the wet. Riding my alloy rims on on of my rim brake the last few days and it has been very wet and the braking has been slow. On my carbon rims the water has to clear but then there is proper bite. It takes moments for the water to clear. I can't say I notice a difference in stopping distance between the two materials.

4) go tubeless. Good tubeless tyres are easy to set up but it is rim dependent. Kinlin make one of the most tubeless compatible rims in the XR31T. There is no better frankly for ease of setup. I don't carry spare tubes just tyre worms in case the sealant can't fix the hole and I have yet to find a hole a tyre worm can't plug. I do find on the odd occasion that I puncture that the sealant (effetto Mariposa) sorts it quite quickly. Too many mistruth about tubeless and frankly the vast majority of tubeless are user error but people blame the concept instead. I do alot of miles on tubeless tyres now and I don't have issues. If I can avoid them on the flinty crap I ride over every day others can.

5) Wider rims are stiffer rims. Stiffer rims are better rims full stop.

6) 25mm tyres are generally quicker on real world roads than narrower tyres. Silva has a good post on this on there blog. Roads are not perfect and the improved comfort is telling you something as there is less vertical acceleration which means you are faster. The right the road the lower the pressures required to minimise rolling resistance. rims that are a bit wider than the tyre show lower CDA but not all 25mm tyres are the same width.

7) carbon rims wear very slowly. I get three to four times the mileage from them compared to alloy rims.

You have so much confused logic it is hard to know what you actually want. If it is the fastest useable wheels then go with 45mmto 55mm deep carbon rims. If you are prone to braking alot on long descents that get your alloy rims hit then avoid carbon if they are your only set of wheels. Very Good carbon rims can be Chinese made.

Otherwise the Kinlin Xr31t is about as aero as alloy rims get. Forget the extra weight it s irrelevant. Build up with tune or carbon to hubs to get a fairly aero light and stiff wheelset that will be a quick as alloy clinchers can be in the real world.

Carbon ti hubs are the alternative to tune for very light hubs. If you dismantle both you will see which is the better hub. Extralite hubs are even lighter and seem to be reliable.

A 1200g alloy clincher set is frankly crap. I know people buy them and like them it does not mean however they are any good. I am being blunt now because it needs to be said clearly. Clinchers that light with alloy rims are not stiff and stiff wheels are just better wheels in many ways.



There is way too much fuzzy logic when it come to wheels.

by Weenie


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