Bekologist

Going to buy a Dynohub this spring for my heavy touring bike. I do a lot of rough roading it and gravel fire roads on my tours, and a 48 hole Schmidt dynohub is mighty tempting.

The question I have is, does anyone think 48 spokes are overkill on a front wheel for a single touring bike?

I'd be matching up to a 48 spoke wheel in the back. I just wonder if 48 in front is just way over the top.

Any input?

cyclintom

WAY overkill. 40 spokes are common on the front of tandems and I've rarely seen a broken tandem front wheel. Lots of broken back wheels though.

CdCf

I'd love to have 48 spokes both back and front, if only rims and hubs for it were easily available here. They're not. Not even 40 is to be found.

royalflash

not if you happen to be a blue whale otherwise very probably

tphelps

Most cycletourists consider that custom built wheels with 36 spokes fr/rr to be more than adequate, and 40 rr/36 fr to be pretty much bomb proof on a single touring bike--even on rougher roads. I'd recommend 14/15/14 double-butted ss spokes, as they offer just a wee bit of give under a heavy load, breaking less frequently than straight-gauge spokes.

Best regards,

Ted Phelps
Central Valley, California

CdCf

I love redundancy!
Did I mention my bike has two front lights (hub dynamo-bulb, battery-LED), to rear lights (two sets of red LEDs), two bells (really only because my first was pretty bad, but when I mounted the new one, I simply let the old one stay on there) and two handle bars! If my fork had had the proper mount for it, I would've had a mechanical disc brake as well in front, together with the rim V-brake.

That, and the fact that I think that wheels look better the more spokes they have!

Bekologist

We're talking rough stuff. Multiple thousands of feet of descent on golfball sized gravel or worse, ripraff, maybe ride to Alaska or do portions of the Continental Divide trail with it, that type of riding.

I was riding some pretty some heinous descents in the Cascades and Olympic mountains this last year.

I caught myself in the thick of some downhills thinking,
can they make this rubble any larger and still have it considered gravel?

I don't have any pictures of the bad stuff, but here's a road washout, and a rockslide in the process of getting removed from the North Cascades Senic Highway, both summer 2005.

NoReg

I think even a moose can get by with 32 on the front, that is a moose with baggage.

I forget what it is but there is some problem with too many spokes. Of course there are the obvious problems of rotating weight, difficulty finding lots of options, getting replacement parts. But I think there are some direct structural negatives, like drilling extra holes in the rims. I have a feeling part of the problem is that if you put 48 spokes on a rim vs (is it a 32 spokes normal MTB wheel) You either tension it with a lot more energy, thereby enormously increasing the stress on the wheel, or you have each spoke reduced in tension so as to keep things in line. So now you need more spoke angle to make up for the sloppy sploke tension, so you need a 140 rear hub. If you do that on a front hub it's narrow to start with, and you want to use a disc brake also, where you need a lot of tension to deal with the spoke angles. I'm not sure you end up ahead. If you fixate on the one issue: more spokes, you are ahead. But every other factor seems to be a negative.

kesroberts

Go for it if that's what you want - the riding you have planned sounds great. I probably wouldn't do it myself since I have never had to even true the 36 spoke stock wheels that came with my bike even after 3 years of pretty hard use.

mtnroads

Mtn bike. Rigid is fine. I also want to ride the GDMBR, and do some other offroad touring, so I am setting up an old Trek 970 (no susp) for the purpose. Lugged chromo frame, XT components, strong 26" wheels with Conti Town & Country tires, Jandd Exped racks = pretty much bombproof and doesn't weigh much more than my 520. Yes, it is slower on pavement, and the riding position still needs work but it should do the job.

goldener

with 48 holes the chance of hub flange breakage is increased.

amaferanga

Surely if you think you need 48 on the front then you need more than 48 on the back????

36 front and back on a well built wheel with tough rims (Sun Rhyno, Mavic EX721) can cope with anything.

Its utterly pointless getting a 48 spoke front wheel IMO.

Camel

Yes 48 is overkill. The spoke flanges are also higher on most dynamo hubs, meaning slightly shorter spokes as well. Meaning slightly stronger spokes.

I'd also give using a dyno hub another thought or two if I were you.

I run one on my brevet bike, but am not using one on tour. I've only ridden at night perhaps a handfull of times while on tour. The few times I did, it was for going out after setting up camp, or from a hostel/pension (usually I go for an evening walk, rather than ride). Battery powered LED lights were perfectly fine, for me, in those circumstances.

Now with the multitude of 1-3W luxeun battery powered LED lights available, there is even less of a need for dynohubs on tour. IMO.

Note also that you would need to have a speed >6-10mph for adequate power generation. That would be a bit faster than I would want to go on an unknown trail descent (AT NIGHT) far from support.

Running dual lights off my schmidt sun hub is adequate on paved descent ~15mph, on a clear night. Track/trail would create way too many shadows (IMO), due to the angle with which most generator lights project there beams.

-Now if your using your generator hub to recharge batteries and such, that's a completely different story. More power to you (ha, ha)! Do let folks know how your rig works. I"d be interested in it, as would other's I'm sure.

grolby

A wheel with more spokes will necessarily have less tension on each spoke. This is not a bad thing. A 48-spoke wheel is stronger than a 36-spoke wheel of like quality. It is simply unnecessarily so. 36 is enough. Rotating mass is also not a problem. Bicycle accelerations are so slow that most roadies are wasting their money to reduce rotating mass by ten grams. It's positively absurd to think that a touring cyclist would want to be at all concerned by rotating mass. It's simply not an issue.

challengea2z

101% over kill not even on my Orange Patriot down hill bike did I use more than 36 spokes, also I only use 36 on my S&M BMX, never felt the need for more spoke, I'm using 32 because Rohloff only make them with 32 and my tourer, and it will be use on and off road, 14 gauge tandem spokes and strong rims that are built well are all you'll need. IMHO I don't think you need more than 36.

vosyer

I have watched your posts for a while and I am also in Puget Sound - you really ride some tough stuff an in weather I would not be caught dead in. I agree with everyone that 48 is "slightly" overkill for a single bike - I use the word slightly because if I could find or was willing to pay for 48 hole I would of bought them for my 700c touring bike - instead I have opted for 40 hole on my my 26 inch bike and 40 hole on my 700c bike and on my tandem I ride 48 hole. Also I seen alot of discussion about flanges in this thread - my comment is that 40 or 48 hole hubs take this into consideration as do the rim makers who put out rims for these rubs and most of the postings on the subject have never handled either. Also just as a learning curve make sure the back and front wheels have the same number of holes - I found myself in a circumstance with a 40 front and 48 rear and didn't have a replacement on board when one broke. And as a FYI there are several big guys in Seattle riding 48 hole wheels on their City bikes and are glad they do.

531phile 

I carry 40 pounds of groceries in addition to my 175 pounds with a 32 rear and 32 front. No problems. Almost a year now with this set up.

NoReg

"Bicycle accelerations are so slow that most roadies are wasting their money to reduce rotating mass by ten grams. It's positively absurd to think that a touring cyclist would want to be at all concerned by rotating mass. It's simply not an issue."

What's absurd is to add 24-32 additional spokes and nipples if there isn't any need to. If one wants the additional strength, if that is what it actually is, that's fine. But there is additional rotating weight. If you don't notice it your bike may already be too heavy.

Here is a good sumary. good coverage of the advantages of many spokes along with the limitations of not being able to max out tension which is a good also.

https://draco.acs.uci.edu/rbfaq/FAQ/8c.8.html

ken cummings

I use 36 front and rear on my touring bike. I also use it for commuting. Total weight of me, bike, and gear was 260 pounds. I took it single-tracking in a local state park on rocky trails several times and had no problem. That was maybe 100s not your 1000s but still on the way thru I would also pick up a nice 20-30 lb rock for my yard. Any secret would be the 700x38 tires. I have broken one spoke in two years, on the rear wheel, cluster side as expected. If you are going to treat your touring road bike like a mountain bike consider starting with MTB-equivalent tires. Or just tour on a MTB.