gerv 

I'll add to the posts about dynohubs. I built up a front wheel with a Spanninga (Velo-Orange) hub. The 1-watt PB Blaze LED I bought with it seems acceptable for street riding. I love not having to worry about batteries and such.

On the negative side, the hub is a little on the heavy side.

BarracksSi

I go with Supernova's point that the weight penalty of a dynohub isn't any more than that of a battery pack.
https://supernova-lights.com/en/produ...amowheels.html (at the bottom of the page)

alan s 

Dynohubs require you to carry the extra weight regardless of whether you need the light. I only carry lights maybe 5 months of the year when the ride home is dark. The other 7 months, I don't need lights at all. For me, the advantages of a dynohub don't outweigh the disadvantages. Nearly my entire comute is on MUPs, so I can get away with little or no light until November.

BarracksSi

I just pooped the weight difference.

FWIW.

BarracksSi

More relevant than poop, though, I always turn on my dynohub bike's lights, even in the daytime. My neighborhood, around Capitol Hill, has so much visual clutter and so many shade trees that I think it's a good idea to stay lit. It seems like drivers are less likely to cross too closely and pull out of their parallel parking spots when I've got the light on.

Arcanum

That brings up a related point: Even in the day time, even if there's not a lot of visual clutter, it's not a bad idea to turn your lights on in the rain for that little bit of extra visibility.

clasher

Whoa, that's a killer deal on that dynamo-disc wheel. I'm still debating if I should get drum or disc at this point though.

BarracksSi

Go with whatever fits your fork. If material matters, I've also seen (and owned) carbon forks with disc mounts, but I'm not sure if there are any that are intended for drum brakes. I'd be a little wary of jerry-rigging the brake arm for a drum hub onto a carbon fork leg.

Andy_K 

I built a set of wheels last year with SRAM X.9 hubs. They're light, have sealed cartridge bearings and take a six-bolt rotor. I've used them for rainy commutes and short track mountain bike racing. I've only put around 500 miles on them so far, but I'm pretty happy with them. If you wanted to save a few bucks, the SRAM X.7 hubs look very similar. SRAM says the X.9's are a few grams lighter and have higher grade bearings.

FWIW, I built them with Salsa Delgado Cross rims. I feel a little weird about having used a non-disc rim for a disc brake wheel, but they fit my price+strength+width+weight requirements better than anything else I found. I'm not sure they would work with anything narrower than 700x28. I've been using 29x2.0 tires with them.

LazurusTaxa

Andy_K, those SRAM hubs look great.. Pretty much just what I am looking for. How have they been for you? Any remarkable ups or downs? I have also been looking at the DT Swiss 370s after I realized they are just the newer version of the DT Swiss Onyx hubs i have and love on my MTB. Anyone had any experience with the newer 370s?

Andy_K 

So far the SRAM X.9's have been great. I'm not really sure how much you can say about a hub. They look nice. They spin well. I had no problems with the build (my first).

The bike I've got them on is a tank, but I've been happy with the performance I've gotten with the new wheels. The real test, of course, will be how well the wheels are spinning at the end of the winter after six months of being saturated in road grit. I didn't get them finished until early spring of this year, and most of the summer the bike they're on was hanging on the wall.

alan s 

. . . and your point is??? It make no sense for me to carry a light on the MVT, towpath and CCT when there is plenty of light from the sun. On Capitol Hill, you should probably be well lit up 24x7.

BarracksSi

I don't know anyone who both lives and works on a MUP, as in, they can ride out the back door of their house, get on it, then ride off into the parking lot where they work.

But, maybe some people do.

My real point is that a couple ounces of weight on the bike is the last thing to worry about unless you're going for a win in a mountain stage race.

LazurusTaxa

Soo.. Thinking of having some wheels built up and going with Mavic TN719 rims front and rear (32 hole), and either XT, Sram X9, or DT Swiss 379 hubs, and DT swiss straight gauge spokes. Anyone have any suggestions, preferences, or tweaks on that setup? I figure that the mtb duty rim and straight gauge spokes will make up for the strenghth lost by going 32 spokes over 36.

electrik

Yeah, great. Super simple to service clean and oil. Can get expensive when bearings go as it's all cartridge and the freehub body has it's bearing press-fit in.

Andy_K 

I wouldn't go with straight gauge spokes. My understanding is that butted spokes are just as strong in the places where spokes typically break. Otherwise, it sounds like a good plan.

tsl

Nope. Go with double-butted. Our old pal, Sheldon Brown explains it best: https://www.sheldonbrown.com/wheelbuild.html#spokes

alan s 

I guess I'm one of the lucky commuters that rides almost entirely on MUPs (15-20 miles each way). The non-MUP portions are on quiet residential streets.

I try to limit extra weight wherever possible, as it all adds up, and takes away from speed, ride quality and enjoyment:

I leave my shoes, belt, lights, tools, lube and locks at work
carry CO2 rather than a pump
use a trunk bag rather than panniers (lighter and more aero)
use a lighter wheelset and tires without sacrificing durability
don't carry a multitool

I figure that adds up to at least 5-7 pounds of gear I'm not constantly hauling around.

LazurusTaxa

Thanks for the tip on the butted spokes! One last question though to narrow down my hub choice. When I spend a winter commuting in the rain, will the sealed cartridge bearings in the SRAM hubs make a difference over the loose balls of the XT Hubs? Of course, the XT hubs are serviceable by me without a shop, but is one preferable over the other?

Edit: Sorry, one more to add to that. Brass or Alloy nipples? Ive heard that Alloy shouldnt be used with disk hubs... But i can get pretty colors with Alloy!

pwdeegan

The TN719s are a good choice, as are the double-butted spokes. FWIW, i've heard stories on corrosion problems from the AL nipples and salt-spray, but honestly, i had corrosion on my brass nipples from NY salt spray too (just cleaned it off, no problems and still rolling fine). The pretty colors are enticing, but given that they'll likely be spinning at high speed, and when not spinning covered in road grime there are probably bigger issues at hand.

I've been lured by cartridge bearings, but owning an XT hub i have to say that the maintenance is really simple and the hub has operated flawlessly. White Industries, Paul, Phil, and King all make pretty hubs, but all of them will need servicing at some point, and the XT (as you point out) is user-friendly. If i had my druthers i'd lose the XT hub and get a nice SON dynamo hub. Also, don't worry about the ISO vs. centerlock issue; just make sure the disc rotor diameter is the same (e.g., a SON20R centerlock will work fine with the corresponding Avid caliper).

Andy_K 

Yeah, I really don't know about the cartridge bearings. In theory, they're better protected against the elements. I'm not sure it really makes a difference. Ask me again next summer. Or, better yet, ask your wheel builder.

ghettocruiser

okay, I'm not really a dyno-hub kind of guy.

But that one with the carbon rim got my attention.

gerv 

That is one significant point. The extra weight is not noticeable for me (who carries so many tools and other crap that rarely get used...)... except when I lift the front wheel!

Having the light on all the time is a nice feature.