Xiamen Carbon Speed 10 years anniversary special promotion

[KaiDeus]

Thanks for the clarification, peter. I wasn`t aware the rims are basically made to order.

Had to change to narrower rims, because winspace is very stingy on clarifiying their tyre clearance on the slc 3.0...They can`t deliver the measurment of the chainstay gap at the wheel.
Be it as it may, i`m looking forward to the wheelset.

[toxin]

Thanks for your thoughtful analyses and comments.  I was just wondering what leads to the conclusion that the farsports version is better? I'm assuming you're referring to aero?

I'm also thinking about safety - it seems like none of the options really use bonding to hold the tension anymore which addresses my concern if it is true (I've had some bad experience with carbon adhesive pull-out in another application).

Yes, aerodynamically, the farsports 5mm spokes are better, othersise the designs sre basically the same.

Yep, LightBicycle made carbon spokes bonded to metal bit for a short while and they were an absolute disaster. There's still someone out there making similar spokes, though they've taken some steps to mitigate the risk. Most of the time they're still an inferior choice though. Their advantages are that they can be a gram or so lighter and fit normal hubs.

[ancientone]

Do you think the 6903 bearings can really lower the rolling resistance ? I am not sure, DT Swiss uses same 6802 and 15267 on their hubs. At least so far we haven't any client saying our hubs with high rolling resistance or anything bad. Anyway we use good bearings, maybe just different sizes with others'.

Thanks. I'll msg you to confirm the details, price and order.

[toxin]

Bigger bearings usually means improved durability, not lower drag

[PeterXu]

Bigger bearings usually means improved durability, not lower drag

I know, normally on MTB hubs, no? Or mainly on front hubs? We use bigger bearings on our in-house MTB boost hubs for now.

[toxin]

On all hubs, but since mtb hubs see much higher and frequent impact loads, bigger bearings are more beneficial on them than road hubs. I think if dt swiss use 6802 on dt180 hubs, then they should be fine for most road riders.

Bigger bearings would theoretically have more drag as they have more balls, but that means the loads are distributed over a larger contact area, meaning the loads on individual balls are lower, meaning they will wear slower. But the larger contact area means there will be marginally more drag, virtually irrelevant amounts for bike applications though. Seals make magnitudes more impact on bearing drag.

The tradeoffs with bearing sizes in hubs are usually size and weight vs durability:
• smaller bearings means lower weight and smaller, fractionally more aero hub
• bigger bearings means better durability against wear and dirt ingress.

[Sakizashi]

On all hubs, but since mtb hubs see much higher and frequent impact loads, bigger bearings are more beneficial on them than road hubs. I think if dt swiss use 6802 on dt180 hubs, then they should be fine for most road riders.

Bigger bearings would theoretically have more drag as they have more balls, but that means the loads are distributed over a larger contact area, meaning the loads on individual balls are lower, meaning they will wear slower. But the larger contact area means there will be marginally more drag, virtually irrelevant amounts for bike applications though. Seals make magnitudes more impact on bearing drag.

The tradeoffs with bearing sizes in hubs are usually size and weight vs durability:
• smaller bearings means lower weight and smaller, fractionally more aero hub
• bigger bearings means better durability against wear and dirt ingress.

I don't know enough about bearings to make a definitive statement on size and choice of bearing regarding size, drag, and durability. I do know enough to know that it's more complex than this, and a first principles approach like this can be really misleading (same as saying X shape is aerodynamically faster based cross-section without taking into account other factors like varying yaw angles)

For example:

• Not all bearings of the same size have the same number of balls. In addition to corrosion issues, this is why i tend to avoid cheap ceramic bearings.
• Material choice and coatings can also matter.
• Preloads can be a huge factor. For example, if you are worried about the load on a smaller area but can manage preload well with the design, a smaller ACB might be a better choice than fitting a larger radial bearing in a design where preload cannot be as well controlled.

[Nkearb]

Thanks for the clarification, peter. I wasn`t aware the rims are basically made to order.

Had to change to narrower rims, because winspace is very stingy on clarifiying their tyre clearance on the slc 3.0...They can`t deliver the measurment of the chainstay gap at the wheel.
Be it as it may, i`m looking forward to the wheelset.

I have a SLC 3.0 in size L. Othersizes may have difference clearances.

The D65-33 fits with plenty of clearance.

Im actually considering buying the D50-36 for my SLC 3. The front would fit easy, the rear most likely fit fine, wouldnt want to go any bigger though

[KaiDeus]

I have a SLC 3.0 in size L. Othersizes may have difference clearances.

The D65-33 fits with plenty of clearance.

Im actually considering buying the D50-36 for my SLC 3. The front would fit easy, the rear most likely fit fine, wouldnt want to go any bigger though

Peter would kill me, if i change the rim again

I don`t understand some chinese frame manufacturers and their tyre clearance claims. Winspace told me that the chainstay clearance would be already tight with a 32mm tyre...
How many mm on either side of the tyre to the chainstay with your setup?

[Nkearb]

On the SLC3 L, the tightest fit is between the widest point of the tire and chainstays. Bit over 38mm measured, so a tire measuring 34-35mm (a 32c gp5000 on a 28iw rim) would be a tight fit. The rim is wider than the tire at 36.6mm but the chainstays spread out enough that they clear this more

[ry]

How do we think the vertical & lateral stiffness/compliance between a 20 carbon spoke wheel and a 24 steel spoke wheel would compare? Data would be better than hypotheses but I understand if it's not available.

I hear of harsher ride being reported on carbon spokes with less perfect road surfaces (ofc also with better aero & weight) but have to expect that 20% fewer spokes may offset that if the baseline was with 24 carbon spokes instead. 

[toxin]

Depends who you ask for the subjective, but usually carbon spoke wheels would still be stiffer. Actual measured data on vertical and rotational stiffness is basically non-existent all we have are lateral stiffness tests. Also, fact is, most carbon spoke wheels are simply overbuilt. We were fine with 20 and 21 steel spokes on the front, why do we need to have just as many carbon spokes? It doesn't make sense.

[ry]

Thanks, Toxin.  That's consistent with the rabbit hole of research I've done over the last couple days.  Appreciate the thoughtful discussion here from people more knowledgeable than I.

I want to get my order in but I'm having trouble picking between 3.8mm carbon, 5mm carbon, or steel CX-Ray spokes for my T1100 D50CU-33.  I'm 60kg fwiw and assuming cross winds won't be an issue. 

The extra cost of carbon spokes is significant but if it makes my bike more fun but not noticeably less comfortable on 32c tires or significantly less safe then it's probably worth it for me. 

[PoulB88]

I would think that with 32mm tires at an appropriate pressure for your bodyweight, the type of spokes in the wheel make no discernible difference to the feeling of comfort.

[toxin]

The stress deformation plots of carbon and steel spokes aren't that different. Carbon spokes just fail at a higher load. No point going 3.8mm over 5mm