Self Evident

This is actually just an incidental and beside the point story that sprang from a recent undertaking while working on an extraneous secondary sidetracked offshoot of a tangtially semi-related ancillary but also not an entirely indicental task that all grew out of a primary project whose objective was to build a new rear wheel, where I considered, and then confirmed, something that had not occurred to me previously - that not all paired-hole hubs (phh's) are the same. Specifically, the spoke-hole offset from one flange to the other is not as I would have expected.

(side note: unless indicated otherwise, as used here-in, "hole" means "spoke hole")

In a normal/simple/standard hub, the holes between the flanges are offset so that if both flanges were right next to each other, the holes on one side would be evenly spaced between the holes of the other. This is so that, collectively, all the holes in the hub are evenly spaced, and will match up with holes in the rim.

With phh's, however, the individial holes are not evenly spaced, because they're in pairs. But I thought that the pairs themselves might be evenly spaced between the two sides of the hub. But, they are not. Instead, opposing pairs are *almost* directly across from one another, so that if the flanges where right next to each other, the holes would overlap a bit. At least, that is the case with the three of such hubs that I have. But, more than that, they are not even offset the same, and thus the holes don't overlap the same, even when the angle between the paired holes are the same on both hubs.

Originally, two of these hubs came from wheels that also had cooresponding paired-hole rims. I'm guessing that is the why for the offsets between the flanges. But I have no real idea other than idle speculation. In anycase, here's the actual "closer look":



Ok, what the holy heck??? The pics are showing up here WAY larger than what I uploaded to photobucket. Oh well... It is a CLOSER look!

Anyway, as can be seen, the silver hub has the holes "closer" together. And in the black hub, the holes are offset such that the left from one flange lines up with the right of the other. Also, the flange-to-flange offset between hubs is in opposite directions.

Anyway, are any others familiar with paired-hole hubs and their hole spacing? Specifically, is one of the two offsets pictured common? It's not a big deal, as it should be evident from the pics that I don't intend to use these hubs again. Altho, as a completely different topic, and just for curiosity, is it possible to replace bearing cups in hubs? If so, I'm guessing the hard part would be finding the right part...

FBinNY 

Looking at hub drill patterns without the context of the corresponding rim hole pattern is pointless.

In the case of your hubs, they might be made for a rim that has groups of 4 holes with normal spacing, then a blank zone between these groups, so it looks sort of like this; o o o o........ o o o o........ o o o o........ etc.

dabac

For Shimano, or similarly constructed hubs, the DS cup is part of the freehub body. The body can be replaced, or the cup replaced with one from another body.


The NDS cup can be knocked out from the opposite side using a drift punch - if the cup overhangs the central cavity. Hubs with slender center shells, it can be hard to get enough purchase to drive the cup out. I once plugged a cup by welding a piece in to be able to knock it out.



Yeah. I've never been able to find cups only. But there's a decent cross-compatibility, so finding a donor hub doesn't ahve to be that daunting.




Haven't handled enough of them to claim authorithy. But it doesn't seem to matter much either way.


IMo the finer details and consequences of hole arrangment is entirely dwarfed by the fact that it's usually done on wheels with fairly low spoke counts.
And for a comparable quality of build, a low-count wheel will have lesser margins than a wheel with more spokes.

fietsbob

Schmidt just introduced a semi radial light weight, paired, almost straight pull front hub (dynamo), paired straight pull (no J bend)spokes.

but intended rims are to be regularly spaced..

Boutique wheels , include Campag, spokes in groups of 3, (not 4)..






....

Self Evident

I understand, and agree if I was looking to build, that a specific rim would need to be considered before considering spoke length. However, the question was, "Specifically, is one of the two offsets pictured common?" Regardless of any rim that may ultimately be mated with such a hub, I am simply curious if there is a common, or more common, radial/phase offset between the flanges of paired-hole hubs.

That's creative!


Yea, this is mostly academic at this point, as I don't intend to use either of the hubs above again. Altho, I might lace them up into the same rim & spokes (not at the same time, of course), just to see if there is any practical difference. I know, that doesn't sound very practical...

andr0id

Most rims don't have the left hole and right hole exactly in the same location, so the holes are going to be in a line. As such, you need offset holes in the hub or you'd have to use and keep track of different length spokes.

Big pain in the arse, no real benefit. So why would any mfg do it?

FBinNY 

Using words like "common" to describe what is already a very uncommon arrangement doesn't make logical sense. Any hub not drilled in the classic zigzag pattern, is already uncommon. I consider all hubs of this type single purpose and part of a non-standard wheel design.

For better or worse, (mostly worse) we're seeing more unique non-standard designs throughout the bike world, moving bicycles and their sub-parts from an era of fixable with a few spare parts and mechanic skill, to one of modular design where entire assemblies are trashed and replaced rather than repaired.

Self Evident

While not the most common, paired-hole hubs, or rims, are hardly "very" uncommon. But they are definately going to become more uncommon to me. While I've rebuilt several (replaced rims or hub with same size part), I've never really been a fan. Can't say why exactly. Oh well. Anyway, I do aggree with the observation of how things are

. And not just with bicycles - with everything. I always try to fix, mend, or repurpose if possible, altho possibly past the point of diminished returns. For instance, I have a collection of old rims that I just can't bring myself to toss in the recycle bin. I mean, they've got to be good for something!

3alarmer 

...people make garden fences and gates out of them here.

Self Evident

That sounds interesting! Can you point me towards some examples? I searched the forum & only got this thread...

3alarmer 

...the majority of people use the whole wheel, but you get a cleaner geometric look if you just use the bare rims.