Singlespeed & Fixed Gear - Hub threading Q

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View Full Version : Hub threading Q


cs1
06-30-05, 10:49 AM
I have several hubs at home that I want to convert to use as a fixed. The question is they are not threaded for a lockring. Does anyone have dimensions for the threading? I have a machinist friend that says he can do it cheap if I supply him with dimensions. Any help would be appreciated.



Tim


dolface
06-30-05, 10:53 AM
do what? machine another set of threads onto the hub?
that MIGHT work, 'tho i'd be surprised if there is enough material there to cut a set of smaller-diameter threads into.

cs1
06-30-05, 11:23 AM
do what? machine another set of threads onto the hub?
that MIGHT work, 'tho i'd be surprised if there is enough material there to cut a set of smaller-diameter threads into.
Exactly, I want to have the other side threaded for a fixed gear with lockring. I just don't have the threading dimemsion for the lockring.


Tim


baxtefer
06-30-05, 11:27 AM
depends what kind of lockring threading you want...
33.5 mm × 24 TPI Campagnolo, Gipiemme, Phil Wood, Miche
1.29" × 24 TPI Shimano, Suntour, Suzue, Surly, Zipp, Corima
33.0 mm × 1 Mavic/French

cs1
06-30-05, 11:33 AM
depends what kind of lockring threading you want...
33.5 mm × 24 TPI Campagnolo, Gipiemme, Phil Wood, Miche
1.29" × 24 TPI Shimano, Suntour, Suzue, Surly, Zipp, Corima
33.0 mm × 1 Mavic/French
WOW, like everything else in biking too many different standards. What is the recomended/most common threading? I love Campy but no one seems to stock their parts.


Tim

bostontrevor
06-30-05, 11:36 AM
Go with the Shimano. It's the most common and there are plenty of quality lockrings to choose from at decent prices. On the other hand, a Campy diameter will require less machining (weakening) of the part.

r0cket-
06-30-05, 11:49 AM
Not to dump on your idea or anything, but I would seriously think twice before doing this. You really, really, really do not want to have your hub implode because you took too much material off.

Erich Zann
06-30-05, 12:22 PM
Not to dump on your idea or anything, but I would seriously think twice before doing this. You really, really, really do not want to have your hub implode because you took too much material off.

I second this idea. The cost of your broken body will be alot more than even the most expensive track hub.

Aeroplane
06-30-05, 01:39 PM
I second this idea. The cost of your broken body will be alot more than even the most expensive track hub.

Perhaps, but at what cost? Think about the guy who first ate Hemlock, or Deadly Nightshade. Granted he may not have had the same abitions as you, but the definitive knowledge gained from him has been useful for hundreds of years. Before him, it was just speculation. Try it, and let us know if you die or not.

bostontrevor
06-30-05, 01:49 PM
Totally.

People are way too frightened. Even if it breaks, it probably won't end up in a fatal wreck.

*new*guy
06-30-05, 01:53 PM
You don't need a lockring anyway.

baxtefer
06-30-05, 02:06 PM
I don't think it would be a problem, if done correctly

For those of you with a flipflop fix-free hub. take a look at both sides. there isn't more material on the fixed side. The hub shell has just been machined a bit smaller on that side to accept the lockring. (otherwise it would have to take different sized bearings on each side)
Then again, an old freewheel hub might be different. I don't have any of those lying around to check.

phidauex
06-30-05, 02:52 PM
Good luck with it. Pay close attention to the amount of material left, and make sure the threading goes far enough in so that the lockring directly engages the side of the cog, instead of just running out of threads.

I'd recommend bringing a real track hub for him to look at and measure, or at least some detailed photos.

Let us know how it works!

peace,
sam

jitensha!
06-30-05, 03:50 PM
oh, and just because nobody's bothered to mention it, lockring threads are reverse (left hand) threads. but seriously, if you're gonna go through all that trouble, buy a track hub. fixie!=cheap.

DiegoFrogs
06-30-05, 08:45 PM
Note also that on the cheap Suzue hub, the fixed and free sides actually do have different sized bearings, cups (I think...) and shields. I don't know how it works on a quality hub, though.

deadly downtube
06-30-05, 09:58 PM
there's an easier method to ride a fixed gear wheel. get a cheap used vintage hub and throw on a random cog with some JB Weld, that cog will never ever come off, it will be atomically and nuclearly and electromagnetically bonded with the hub.... you can't ever switch cogs, but, once you know your gearing, you dont want to change anyways.

icithecat
06-30-05, 10:41 PM
Please try this and report back. I can source lots of older campy or other quality freewheel hubs. This could be a mover if it works.

cs1
07-03-05, 04:06 AM
Perhaps, but at what cost? Think about the guy who first ate Hemlock, or Deadly Nightshade. Granted he may not have had the same abitions as you, but the definitive knowledge gained from him has been useful for hundreds of years. Before him, it was just speculation. Try it, and let us know if you die or not.
LOL, sounds like a plan to me. It looks like the road to hell is paved with good intentions.

Tim

travsi
07-03-05, 06:28 AM
...i think more importantly are the logistics of this project. are you going to be able to get the hub into a lathe in a way that its absolutely centered and tight enough to cut good threads into?