First, let me dispense with something real quick:
Lemond Poprad 130mm 135mm Rear Disc Mountain Road Cyclocross Brake Rotor Spacers Spacing Frame Steel True Temper Mounts Hubs Spreading Stretching Removing
Phew... I think that'll do it. You see, I'd like this post to show up in the future when folks are searching for answers. The kind of answer I was searching for and couldn't find, but figured out.
Allow me to summerize the issue that was touched on in yesterday's post:
Road bike rear hubs are spaced 130mm.
Mountain bike rear hubs are spaced 135mm.
Road bikes rarely have disc brakes.
Mountain bikes often do.
Lemond Poprad Disc frames are 130mm.
Therefore, mountain bike rear hubs don't fit.
It's hard to find a manufacturer making 130mm rear disc hubs.
The most common questions I found asked on the internet:
Can't I just remove 5mm worth of spacers on a mountain bike hub?
Can't I just stretch the frame 5mm?
The answer to both is NO.
Of course, let me qualify this in the way I often need to in the shop. You CAN do whatever you want. Remove spacers, hacksaw it, stretch it. It MAY work just fine. There's things that can be done and modified to make just about anything work. I understand that, but you should understand it's just not the way you should do it.
In regards to stretching the frame, it's only even an option if the frame is steel. Under NO circumstances should you stretch out a carbon or aluminum frame. That's just asking for failure. Don't believe me? Next time you drink a soda, bend the empty can in half. Now bend it back. After a few times, you'll see it split. Now imagine bending the backend of your aluminum frame back and forth each time you take your rear wheel out. The reason you shouldn't stretch a steel frame is similar; it stresses the rear end of the bike in a way the frame builder did not anticipate. This could lead to premeature wear and/or failure. Granted, the steel can handle it better than aluminum, but it's still not good for it.
Now, removing spacers and hacking off the quick release axle; don't. In theory, it makes sense. If you need 130mm and have 135, remove 5. Done and done. But after discussing it with a major aftermarket hub manufacturer, I learned why this doesn't really work...
Your disc rotor needs to be in a very specific place in order to line up with the caliper. Your cassette needs to be in a very specific place to accommodate proper chainline and to clear the frame. These measurements are taken inward from the end of the axle. Therefore, removing 5mm of spacers, in any combination from either side, will greatly effect those spacings and measurement. Thus, your disc rotor and/or cassette will not properly line up. When hub manufacturers produce these different hubs, the 5mm difference is somewhere in the middle of the hub, not the ends.
If you need a 130mm rear disc hub, it looks like you're stuck like I am. Phil Wood, Chris King or Velocity, if you want to build a wheel. Bontrager or Mavic, if you want a wheelset.
Wednesday, August 19, 2009
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10 comments:
Did you look at this? http://www.sheldonbrown.com/frame-spacing.html
Lots of people are running their poprads with 135mm hubs it seems.
I have seen that article, as well as many claims that people are running 135mm hubs on their Poprads.
1. I'd point out that Poprads came in Disc and Canti versions. Spreading the frame on a canti version would cause less alignment issues.
2. Most of those people are just spreading the frame with the hub, not cold setting it. Sheldon cautions against that as I did, in the article you linked.
3. My main concern is that the dropouts set at 130mm are parallel to each other. There is simply no way to properly bend the rear end open, especially with Sheldon's method, that maintains this. Therefore, your rear derailleur and disc brake will not be in the position they are intended for and the dropouts will be at a slight angle.
As I stated, I'm well aware that you CAN make that method work. There is generally enough adjustment in the disc and derailleur to accomodate it. That said, it still isn't the proper way to handle this (buying the correct parts is).
My greatest concern is that the Poprad Disc frame is irreplaceable, so if I can fix/upgrade it without permanently altering it, and potentially damaging it, that's preferred.
I also question whether Sheldon Brown would have suggested such a process on a higher end, more lightweight tubeset like True Temper OX Platinum.
OK, where can I get a 130mm King disc hub?
I'm not sure where I heard that was available. Looking at their site, it isn't. I wonder if it is an unadvertised option?
I have the same issue with a 2007 Litespeed OBED 29er frame. You can buy a 135 King ISO hub and replace the one piece axle with a two piece 130mm and voila! I didn't say it would be a cheap fix.
That is *exactly* what my post was created to warn against. I'm very happy for you, that changing out those axles worked for you, but the spacing is incorrect and all the hub manufacturers I spoke to said, "no" when I asked if what you did is acceptable...
I also haven't found anything by chris king at 130/disc spacing... though the phil wood site does look like they have a solution. ($489 for a single rear hub. ouch!)
I keep trending towards just buying another set of the oem select disc wheelsets, but know they will just beat up as quick as this first pair has.
So, what did you end up doing to address this?
What I have done is:
1. Accept that when the time comes, I'll have to ante up and buy the Phil Wood rear hub (unless a better alternative is available then). There's worse things than *needing* to buy the nicest hub on the market.
2. Chosen to save some money by using a Paul hub on the front, which I feel is almost equal in quality at a fraction of the price.
C. In the meantime, rebuilt the front wheel with a n asym rim from a Race X Lite rear wheel (which is eyeletted and made in the USA), and Wheelsmith spokes. Also, repacked the hub with new Phil Wood grease. The end result is at least a nicer wheel than the Select was originally (now I just need a rim for the rear).
For the record, the Velocity option definitely would be an affordable, quality option. The only reason I'm not considering it is because I want the wheels to be silver, and that's not an option with Velocity. Vain, I know.
Also check Royce UK. They've come with a very nice disc hub in 130 mm (not cheap, but not as expensive as PW):
http://www.royce-uk.com/
I reckon a Royce back and Paul frount would make a AWESOME hubset
I once heard a story about the world's smallest drillbit, made in Germany. Some manufacturer in the UK ordered one, drilled a hole down the center if it, and sent it back. The moral of the story? Manufacturers in the UK know what the f**k they're doing!
That said, the Royce hubs are beauuuutiful, but for that money, I'd support my home state's economy and fork the $$$ to Phil Wood...
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