The wheelbuilding thread

[pushstart]

Yeah, I now the Flo folks will tell you that the Flo30 is a faster wheel than the Alpha 340 would be on anything but the steepest climbs, given that aerodynamics trumps weight. But I can appreciate that light wheels do *feel* faster to get up to speed on climbs, etc. I am sure you have seen their blog on aero vs weight.

Either way we are talking about marginal differences.

I also have a set of Flo30 rims that I built into 28/28 disc-brake wheels. While they are 200-300g heavier than the wheels they replaced, they seem to be just as fast (or a tiny bit faster) according to Strava. I haven't done back-to-back testing, but I am sure the math that Flo presents in support of those claims is sound.

Of course, if you are choosing between two non-aero wheels, I would go lighter too (or between two aero wheels). And of course this is WW.

So, it sounds like a 24/28 Alpha 340 build would be a nice setup for your weight.

[bm0p700f]

I have some aero wheels and similar weight higher spoke count wheels. Difference are real but small. I have tried lighter wheels and to be honest I never felt faster on them, maybe very light and aero but the 1kg wheels I built for someone (24mm deep carbon tubs on novatec hubs) felt a bit like a spring in terms of flex. The lady they were for is light so they would work out for her but for me I am not so sure.

I have tried a low weight 18F/24R setup with stan rims and it is surprisingly stiff but the hub bracing angles are excellent on these. The 24F/28R with the stans rims would be ideal but I would try a more aero setup, Pacenti SL23 rims 18F or and 24R with Dura Ace 9000 hubs or 20F/24R with White Industries T11 hubs. That will out perform as it is the stans build as it is stiffer, wider and more aero while being only be a 150g or so heavier.

[epiphanyboz]

WW, I am building some mountain bike wheels with Stans Podium MMX rims and Sapim Super CX spokes. Stans recommend using nipple washers to prevent the rims cracking or dimpling but Sapim do 3 styles of washer - round, oval and tapered (HM) and I can't find any advice on which type to use. Which style should I use on Podium MMX rims?

Many thanks,

Dominic

[pushstart]

I think the default nipple washers to use -- unless you are using rims that specifically need bigger washers -- are the polyax round washers.

[mentok]

28 lasers on the rear paired with a pacenti sl23 or hplus son archetype (tbd) for a 90kg rider. thoughts?

[jooo]

Go Comps/Race on the DS.

Also, what hub? The flange spacing can make a big difference between one hub and another.

[kauphy]

I recently built up a front wheel - DT Swiss RR440, 24h, DA 9000 front hub, Sapim Lasers and radial lacing. What kind of tensions do you aim for for a radially laced front wheel? Thanks.

[Orfitinho]

90-100 kgf.

[bm0p700f]

Mentok, sound good with decent hubs. Sapim race DS is ideal and 2x or 3x lacing. A novtec, Miche Primato, White Industries T11, Shimano Dura Ace 9000 are all good hubs that will work well for a long time and cover all levels of budget/bling.

I do front wheels at about 1000N. Where does this kgf come from. Force/tension is only measured in Newtons, or it should be.

[F45]

It irritates me that so many entities use the mythical kgf unit (including the Park TM-1 tension card). Kg are mass, not force. But we do it here as well in the Gallery section. "Weights" must be listed in kg. Derrrrrrp.

[Orfitinho]

100 KgF ~ 1000 Newton

http://en.wikipedia.org/wiki/Kilogram-force

[pushstart]

Yeah, I use kgf because everyone does. Luckily conversion is trivial.

Why do y'all use such low tension in front? I use 120kgf (~1200N I guess). Though my recent wheelsets are all disc-brake, so that is a difference. In general I use max tension rated for a rim, though.

[bm0p700f]

rim brake wheels do not fatigue spokes so it does not matter. For disc brakes though the front wheel must be treated and tensioned like a rear.

[pushstart]

I understood that the bulk of spoke fatigue (or at least forces acting to deform rim or slacken spokes) was due to stresses from weight on wheel / hitting obstacles (e.g. potholes) and not from braking forces -- or even drive torque in the read wheel. (But still would make sense that the rear wheel spokes would suffer more, given rider weight distribution.)

I might well be wrong; that was just what I remembered from Jobst Brandt's book. I will reread that section.

[bm0p700f]

Disc brake forces are maybe up to ten times pedaling torque so these can be fatigue inducing.

Radial stiffness of a spoke wheel is huge and the tyre takes the vertical sudden loading so lumps and bumps should not cause to much fatigue but over time I suppose it adds up. Lateral flex must cause bigger tension changes and can result in NDS spokes going slack. That is fatigue inducing and quickly. So personally I think lateral loads do spokes in which is why laterally stiff wheels last.