Thursday, January 06, 2022

WORD Is The Word

The Paul Components Disc WORD Hub (Image courtesy of Paul Components)
 Back when I was doing my "Bikes of 2021" posts I covered my Twin Six Standard Rando v2 and mentioned that I had pretty much arrived at what it would be for a set up. No big changes were planned at that time. 

Well, I forgot one thing....

Whenever I set a bike up single speed anymore I generally just use a geared hub, some spacers, and a cassette body compatible cog. It's easy to do and you don't have to use a special hub. However; part of the whole single speed experience is the joy and feeling one gets when using a single speed specific hub. 

Why? How could that even matter? 

Well, it has to do with wheel structure and why rear wheels are not as strong and stiff as they could be. Are geared rear wheels 'stiff enough'? Yes......and no. They work, certainly. As a structure, we've figured out how to engineer a compromise to be as good as it can be within the given boundaries. However; when running a single cog, you do not have those same boundaries. 

Look at the Paul Disc WORD hub above. It has threads on the hub shell on the right. Let's imagine that you are going to thread on an old seven speed free wheel to that interface. Now imagine how that would look. The cogs would hang out past the end cap of the axle on the right. There isn't enough room for seven cogs on that side! To make that work you'd need to move that spoke flange on the right there more toward the center of the hub. But now look at how that changes the triangulation of spokes to an imaginary rim here. Not good.....

The spokes on the left don't use the same angle as the spokes on the right to get to the rim.

Spoke angle is critical for wheel strength. Too flat an angle from the hub to the rim with too narrow a distance between hub flanges results in a weaker wheel than if you have more angularity from hub to rim and a wider spacing between the flanges. This is- partially - why we have Boost spacing on mountain bikes. 

Single speed rear hubs can take advantage of wider flange spacing, resulting in more angularity of the spokes from hub flange to the rim, which ends up giving you a stiffer, stronger wheel. Of course, the compromise there is that you only get one gear in the back! (There are always compromises to any choice regarding bicycle design) 

This hub will get laced to a Velocity Blunt SS rim.
And can feel a difference. It is better for single speeding to have a specific hub for the job. Because I know this, I wanted to get a single speed specific 12mm through axle rear hub for the Standard Rando. So, yeah......who makes those? Well, come to the source of single speed specific rear hubs (outside of track bike hubs) and you'll find out. That would be Paul Components, who have been making their Wacky One-speed Rear Device (WORD) hub since the late 1990's. They have expanded the design's range to cover disc brakes and now through axle interface hubs as well. So, I went to them for a look. 

Turns out they were out of stock in mid-2021. Big surprise! Getting anything then was a crap shoot. Still is..... Anyway, I put a rear hub on back order, (what they really have is a sort of "Item Watch", but basically the same thing) Then I completely forgot about it. Last week I got an e-mail notification. "Hey! You said you wanted one of these last Summer. Still interested? If so, get online and fill out the order and payment page," 

Those weren't their exact words, but basically- that's how that worked. So, someday in the future, I'll have that rear hub to lace up. It's going to happen...... Stay tuned. 

I'll be lacing the hub to a Velocity Blunt SS rim I already have in hand, so as soon as that hub arrives......


Tomcat said...

Hey this build looks familiar! I'm loving the set you built up for me last year. Love that paul hub - nothing quite like it out on the market today.

Exhausted_Auk said...

Do you know if anyone makes a thru axle fixed gear hub (presumably disc)?

Guitar Ted said...

@Exhausted Auk - I don't believe that there are any 'off-the-peg' solutions. Fixie Dave had one custom machined for his Boost spaced MTB a while back. But I don't know of anything else through axle AND fixed gear compatible.

What needs to happen is to have someone make a hub with Center Lock splines on each end and then have cogs made to slip on Center Lock splines. Then those could be held on with traditional Center Lock rings. You'd be limited to how small a cog you could go down to, but the through axle does that anyway, so.........