Singlespeed & Fixed Gear - re dish?

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SD Fixed
06-22-03, 12:03 PM
What does re dish a rim mean? In converting a rim to single speed, can some one explain to me what happens?

It seems sometimes you can fix the given hub to a fix, and others you must "re dish"?

I'm a nooooooby..


don d.
06-22-03, 12:36 PM
The rim on a rear road wheel is not centered between the flanges of the hub; it is centered between the dropouts. Since their is a gear cluster on the right side of the rear hub, there is more space between the right hub flange and right locknut than there is between the left hub flange and left locknut. So, when you center the rim between the locknuts, it will be more towards the right hub flange than the left, so that if you look at the wheel from the top down, ithe way the spokes angle out of the hub flanges will bear a resemblance to a "dish", flat on one side(right/gear) and domed on the other(left)side. This is called "dish", a technically specific term no doubt thought up by an MIT grad with more math skills than you and I would ever want.

So-o-o, when someone says to re-dish your wheel, what they are really trying to say is re-center it between the hub locknuts. In your case, I would guess you are using a road hub on a single speed, so, since there is no gear cluster, you can respace the locknuts (if possible, not enough info here)so they are equal on both sides(or however would give you the proper chainline with the single cog and frt. chainring), then re-dish the rim accordingly. Clear as mud? If not, remember, there are no stupid questions, just stupid answers to questions. (Ask for clarification)

SD Fixed
06-22-03, 12:42 PM
I don't have the bike yet, or for that matter the wheel. I'm trying to learn it all before I buy one, so I know what I may need to do when I actually get the bike.


don d.
06-22-03, 12:55 PM
What are you considering buying or doing?

SD Fixed
06-22-03, 12:57 PM
I'm going to buy a used bike, and if it has 700 CC wheels, and the rims are in decent shape, I'd like to reuse them. I get the feeling you can use a stock hub in some cases. So, if I find a decent bike with a decent 700cc wheel, I'd be willing to shell out a wee bit more.

don d.
06-22-03, 01:00 PM
You know not to buy something with a freehub, right?

SD Fixed
06-22-03, 01:09 PM
Originally posted by don d.
You know not to buy something with a freehub, right?
Uh, no. Define free hub.

don d.
06-22-03, 01:21 PM
If you want to use the wheel/hub on the bicycle you buy to put a single cog or single freewheel on, the hub must be an externally threaded hub with a freewheel on it that you can remove. A track hub is an example(find a picture of one somewhere, i don't know,, maybe the campagnolo web site has a picture of a track hub. Notice the external threads to receive a cog).

A freehub is a more modern hub design that has the freewheel body threaded into the hub internally with no external threads for a cog or freeheel to thread onto. All current sytems on the market are freehub designs. You can buy a bike with a freehub, but you will have to either replace the wheel or replace the hub and rebuild the wheel.

You can put a single cog on a road hub(that will probably set off the masses), but you should take special precautions that can be discussed when you get to that stage. You can put a single freeheel on a road hub w/o special precautions.

SD Fixed
06-22-03, 01:24 PM
Okay, I get the basics of it now. Thanks.

I've been eyeing a few bikes here and there, but haven't made it to a swap meet or flea markette yet.

don d.
06-22-03, 01:27 PM
If I were you, I would be sure of my size b4 I bought a bike. Your previous posting about bikes on ebay was a pretty broad range of sizes. Have you determined a frame size to buy yet?

SD Fixed
06-22-03, 02:54 PM
The main reason why I posted a large selection was for an idea of what type of bikes to consider. I'm 6'2, so I'm trying to find a bike similiar to my road bike's size.

Rev.Chuck
06-22-03, 08:33 PM
Look at the older steel bikes, early Treks, or Paramounts. You are more likely to get a wheel with a freewheel hub. The old bikes ride really nice as well.
If you end up buying a hub get a Suzue, they are cheap and work well. The Suzue would have to be spaced to fit your frame as they come 120mm

pitboss
06-22-03, 09:19 PM
If you go swappin' or flea-marketing, bring a tape measure with. This way you know what you are getting for sure. Just a little tip...:D

pitboss
06-22-03, 09:21 PM
OH YEAH-
You can also convert a freehub with the Surly Fixxer. Make sure the freehub matches the year/brands the Fixxer does.

Repp5
06-23-03, 06:41 AM
Originally posted by William Karsten
Uh, no. Define free hub.

Aren't you looking to build a single speed (not fixed gear)? If so I think a freehub is OK, I just did a freehub conversion over the weekend.

I'm sure you have looked HERE (http://www.sheldonbrown.com/singlespeed.html) .

captsven
06-23-03, 08:20 AM
Yo Bill

I am 6'5" and ride a 60cm roadbike. I would guess you would fall somewhere in the 58-60cm range.

I am not sure I you want a fixed gear or a single speed. With either one you may or may not need to redish the wheel.

dumpstervegan
06-23-03, 08:26 AM
As far as measuring goes here is how I was told to do it:

How to Measure your Inseam: (Mi)

- Make sure you are standing up straight, on a hard surface, in bare or socked feet, with your feet 4 inches apart and your weight evenly distributed. For maximum accuracy and comfort you should wear your biking shorts.

- Measure vertically from the base of the pubic symphysis to the floor. Placing a book or similar size object in the crotch area, while exerting a small upward force, provides a good reference for this location.

- Make sure the tape measure is perpendicular (90 degree angle) to the floor, run the tape measure down from the upper edge of the book to the floor.

- Repeat this measurement 3 times, and then average the results for your inseam length.

- Round the calculated results to the closet whole number. (54.5 cm = 55cm)

Example: M#1 + M#2 + M#3 = Sum of measurements

Sum of Measurement / 3 = Average Inseam Length

Average Inseam Length * 0.67 = Road Frame Size

Taken from http://www.plaines.com/page.htm?PG=fitguide