The wheelbuilding thread

Wheels, Tires, Tubes, Tubeless, Tubs, Spokes, Hookless, Hubs, and more!

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The spirit of this board is to compile and organize wheels and tires related discussions.

If a new wheel tech is released, (say for example, TPU tubes, a brand new tire, or a new rim standard), feel free to start the discussion in the popular "Road". Your topic will eventually be moved here!
Seribert
Posts: 7
Joined: Fri Mar 24, 2023 1:52 pm

by Seribert

dsveddy wrote:
Seribert wrote:
Thu May 16, 2024 11:52 am
I need some help with retensioning a wheel. I got a farsport Kaze 58 wheelset and I started to service it. Front wheel is alright but the rear wheel is tensioned on the ds to 120kgf pretty evenly. But the nds is only tensioned to around 50kgf. Is the nds tensioned to low (especially since it’s a disc wheelset) and how can I retension the nds without throwing the dish out of place? :)


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Spoke tension imbalance just a matter-of-fact on the rear wheel, since the bracing angle is going to be different for both sides. If the wheel is dished, true, and your DS spokes are at the proper tension, then you have the correct NDS tension. Rims will be specced to a peak tension that is specific to the side of the wheel with lower bracing angle, i.e. "120~130kgf for rear drive side". AFAIK the non-drive side spokes can be any tension as long as it is lower than the max spec tension.
Awesome thank you :)


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danridesbikes
Posts: 114
Joined: Wed Feb 24, 2010 8:27 pm

by danridesbikes

20h rear XDR hubs for rims brakes, apart from Hope RS4 what other options do i have?

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PaulHenri
Posts: 3
Joined: Mon Aug 19, 2019 1:49 pm

by PaulHenri

Ahoy !
Toe is broken so i'm thinking of a new wheelset while recovering... I was thinking of something like this, for a 24 spokes build - 99% use on road, to replace my GRX Alloy wheelset. No gravel/mtb intended other than the canal road (fine gravel or even tarmac sometimes) :
Hubs : DT 240 EXP Front & Rear (Could use some suggestion here, 12mm thru axle, if there is a cheaper alternative without compromising the weight)
Rims : Deerobust 340g 700C Carbon Rims 31mm Wide 35mm Deep 31GAR35
Spokes: DT AeroComp
Nipples : Aluminium nipples

Anything i should be aware of that i have not seen ? Total wheelset weight should be under 1400 gr if my calculations are right. Budget around 800 €

dsveddy
Posts: 103
Joined: Tue Jan 17, 2023 8:56 pm

by dsveddy

PaulHenri wrote:
Fri Jun 14, 2024 6:21 pm
Ahoy !
Toe is broken so i'm thinking of a new wheelset while recovering... I was thinking of something like this, for a 24 spokes build - 99% use on road, to replace my GRX Alloy wheelset. No gravel/mtb intended other than the canal road (fine gravel or even tarmac sometimes) :
Hubs : DT 240 EXP Front & Rear (Could use some suggestion here, 12mm thru axle, if there is a cheaper alternative without compromising the weight)
Rims : Deerobust 340g 700C Carbon Rims 31mm Wide 35mm Deep 31GAR35
Spokes: DT AeroComp
Nipples : Aluminium nipples

Anything i should be aware of that i have not seen ? Total wheelset weight should be under 1400 gr if my calculations are right. Budget around 800 €
Not sure how GB customs works out for you, but you could potentially save a lot of $$$ with hubs like GOLDIX R240SL, which are DT240 knock-offs (but not copies). Quoted weight is 245g for the set. Really depends on how much you care about bearing/machining quality. My GOLDIX hubs have been fine but certainly are not as precise as a DT set. The bearings they specced are decent--have steel cages instead of plastic. Or you can always pop them out and replace with nicer bearings if you want another step in the project.

The other choice I'll vouch for is Pillar wing for cost and weight savings. If you really want a more robust spoke you can go up to a Wing 21 or 22 instead of 20, but the wing 20s are already supposedly more robust than Aerolite/CX-ray. Again, really depends on the pricing you get in GB, here in the US everything DT is quite expensive compared to chinese parts

jlok
Posts: 2516
Joined: Tue Jun 30, 2015 3:30 am

by jlok

Anyone built front disc wheel with 14:7 on a 28-hole J-Bend hub? It's marginally lighter thatn 24 spokes and a tad-bit more lateral stiffness? What is the draw back?
Rikulau V9 DB Custom < BMC TM02 < Litespeed T1sl Disc < Giant Propel Advanced SL Disc 1 < Propel Adv < TCR Adv SL Disc < KTM Revelator Sky < CAAD 12 Disc < Domane S Disc < Alize < CAAD 10

joss
Posts: 61
Joined: Fri Feb 18, 2022 4:39 pm

by joss

Which rim will be more aero?
Will build an all road bike, tires should have about 32mm

Also not sure if I should go with 30mm GP5000 because they likely blow up a bit?

ImageImage

dsveddy
Posts: 103
Joined: Tue Jan 17, 2023 8:56 pm

by dsveddy

jlok wrote:
Mon Jul 15, 2024 3:03 pm
Anyone built front disc wheel with 14:7 on a 28-hole J-Bend hub? It's marginally lighter thatn 24 spokes and a tad-bit more lateral stiffness? What is the draw back?
Main drawback is that peak stresses at the spoke holes in the rim and the hub will be higher on average, since you have fewer spokes to distribute the load. That being said there's a lot of ultralight rims with super low spoke counts (i.e. CRW CS--16 spokes in front) that seem to handle the added stress, so I really am not so worried about 21 spokes. A mechanic on reddit commented on a thread that asymmetric builds tended to have more spoke failures in practice. The other concern is if a 28h hub is designed to handle the higher peak stress that would come from running 21 spokes, since a 28h hub flange theoretically could be designed around lower peak stresses at each spoke hole since the stresses are distributed over more spokes. On the other hand, for a lot of hubs, hub flange design doesnt really change with hole count, and non-weenie hubs tend to be overbuilt anyways, so arguably it's fine. Lastly, 2:1 lacing hubs are asymmetric in their spoke-hole diameters to better-help balance out the tension across the sides, since the change in resultant force due to the asymmetric bracing angle on a road disc front hub is not 2:1. Typically, 2:1 hubs have a much larger flange diamter on the crossed side compred to the straight-pull side--using a 28h hub means you will not benefit from fine-tuning of flange diameters to suit the lacing pattern. Counterpoint, is that most symmetric-pattern hubs don't have asymmetric flange diameters to compensate for the difference in bracing angle, so this might be irrelevant.

dsveddy
Posts: 103
Joined: Tue Jan 17, 2023 8:56 pm

by dsveddy

joss wrote:
Mon Jul 15, 2024 4:16 pm
Which rim will be more aero?
Will build an all road bike, tires should have about 32mm

Also not sure if I should go with 30mm GP5000 because they likely blow up a bit?

ImageImage
NXT34ARX will be faster with a smooth/slick tire that is 31mm or narrower when mounted. Anything 32mm or wider is going to to be slightly faster on the NXT35CGX.

Reasoning being: the 34ARX is narrower and has a profile that theoretically minimimizes wake under laminar flow conditions, which will definitely be faster. The 35CGX will not suffer from flow separation off the tire for wider tires (maybe up to 34mm?), but the big bulb shape will generate a lot more wake and be slower than the 34ARX under "ideal" airflow. As soon as you put a tire wide enough to cause flow separation, the 35CRX will be marginally faster because it's a slightly deeper endplate/spokes will be slightly shorter.

jlok
Posts: 2516
Joined: Tue Jun 30, 2015 3:30 am

by jlok

dsveddy wrote:
Mon Jul 15, 2024 4:32 pm
jlok wrote:
Mon Jul 15, 2024 3:03 pm
Anyone built front disc wheel with 14:7 on a 28-hole J-Bend hub? It's marginally lighter thatn 24 spokes and a tad-bit more lateral stiffness? What is the draw back?
Main drawback is that peak stresses at the spoke holes in the rim and the hub will be higher on average, since you have fewer spokes to distribute the load. That being said there's a lot of ultralight rims with super low spoke counts (i.e. CRW CS--16 spokes in front) that seem to handle the added stress, so I really am not so worried about 21 spokes. A mechanic on reddit commented on a thread that asymmetric builds tended to have more spoke failures in practice. The other concern is if a 28h hub is designed to handle the higher peak stress that would come from running 21 spokes, since a 28h hub flange theoretically could be designed around lower peak stresses at each spoke hole since the stresses are distributed over more spokes. On the other hand, for a lot of hubs, hub flange design doesnt really change with hole count, and non-weenie hubs tend to be overbuilt anyways, so arguably it's fine. Lastly, 2:1 lacing hubs are asymmetric in their spoke-hole diameters to better-help balance out the tension across the sides, since the change in resultant force due to the asymmetric bracing angle on a road disc front hub is not 2:1. Typically, 2:1 hubs have a much larger flange diamter on the crossed side compred to the straight-pull side--using a 28h hub means you will not benefit from fine-tuning of flange diameters to suit the lacing pattern. Counterpoint, is that most symmetric-pattern hubs don't have asymmetric flange diameters to compensate for the difference in bracing angle, so this might be irrelevant.
Thank you for your explanation. Sounds like not too much consequence and worth a try.
Rikulau V9 DB Custom < BMC TM02 < Litespeed T1sl Disc < Giant Propel Advanced SL Disc 1 < Propel Adv < TCR Adv SL Disc < KTM Revelator Sky < CAAD 12 Disc < Domane S Disc < Alize < CAAD 10

MarkMcM
Posts: 187
Joined: Fri Mar 26, 2010 4:24 pm

by MarkMcM

dsveddy wrote:
Mon Jul 15, 2024 4:32 pm
jlok wrote:
Mon Jul 15, 2024 3:03 pm
Anyone built front disc wheel with 14:7 on a 28-hole J-Bend hub? It's marginally lighter thatn 24 spokes and a tad-bit more lateral stiffness? What is the draw back?
Main drawback is that peak stresses at the spoke holes in the rim and the hub will be higher on average, since you have fewer spokes to distribute the load. That being said there's a lot of ultralight rims with super low spoke counts (i.e. CRW CS--16 spokes in front) that seem to handle the added stress, so I really am not so worried about 21 spokes. A mechanic on reddit commented on a thread that asymmetric builds tended to have more spoke failures in practice. The other concern is if a 28h hub is designed to handle the higher peak stress that would come from running 21 spokes, since a 28h hub flange theoretically could be designed around lower peak stresses at each spoke hole since the stresses are distributed over more spokes. On the other hand, for a lot of hubs, hub flange design doesnt really change with hole count, and non-weenie hubs tend to be overbuilt anyways, so arguably it's fine. Lastly, 2:1 lacing hubs are asymmetric in their spoke-hole diameters to better-help balance out the tension across the sides, since the change in resultant force due to the asymmetric bracing angle on a road disc front hub is not 2:1. Typically, 2:1 hubs have a much larger flange diamter on the crossed side compred to the straight-pull side--using a 28h hub means you will not benefit from fine-tuning of flange diameters to suit the lacing pattern. Counterpoint, is that most symmetric-pattern hubs don't have asymmetric flange diameters to compensate for the difference in bracing angle, so this might be irrelevant.
A couple of comments:

As you say, the dynamic component of stresses will be higher on a 21 spoke wheel (14:7 lacing on a 28 spoke hub) than a 24 spoke wheel (1:1 lacing), but depending on flange offsets, the total stresses (dynamic + static) may be lower on the 21 spoke wheel. That's because a 1:1 laced wheel will have higher stresses on one side, but a 2:1 lacing may have a better balance of stresses. This is mainly a benefit on highly dished wheels, such as some rear wheels which may have a flange offset ratio of 2:1 or more. But the OP asked about a front disc brake wheel, which will have a a much smaller amount of dish. For front disc brake wheels with little dish, 2:1 lacing may actually result in higher static stresses on the non-rotor side than there would be on the rotor side of a 1:1 laced wheel. The combined higher static and dynamic stresses would make a 2:1 laced front disc brake wheel less advantageous from a durability point of view.

There is little benefit in "fine tuning" flange diameters, as flange diameter plays little role in wheel performance. The main significance of flange diameter is for how many spoke holes can be drilled through it while still leaving enough material between the holes to bear the spoke forces. In terms of bracing angle, the main factor is flange offset (distance from the center of the hub), not diameter. For example, say a rim with a 580mm ERD is laced to a hub with flanges that have a 40mm diameter and 40mm offset (a typical rim brake front hub). For radial lacing the spoke bracing angle will be 8.4*. If the flange diameter was increased to 50mm (5mm difference in radius), the bracing angle would be increased to just 8.6*. But if instead the flange offset was increased to 45mm (5mm difference in offset), the bracing angle would be increased to 9.5*. So why do some hubs have different left and right flange diameters? The primary reason is the geometric constraints imposed by the hub mechanism. For example, the flanges on each side of the hub have to larger than the bearings inside them, so using larger bearings requires larger flanges. The drive side flange diameter must be larger than the freehub diameter, and if the freehub ratchet is inside the flange, the flange must also be larger than the freehub mechanism. On centerlock disc brake wheels, the left flange must be larger in diameter than the centerlock splines.

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