Singlespeed & Fixed Gear - Republic bikes

a "high ten" frame will weigh more and flex more than a frame made from cromoly.

Next lesson is that if a frame has a sticker saying that it's cromoly doesn't mean that all of the 10 tubes are cromoly. A frame can have 1 cromoly tube with the sticker on it. the rest of the tubes can be high-ten.

End of the lesson, there's seamed cromoly and seamless. A seamed tube starts out as flat plate and is rolled then welded. You will not see the seam, but it's there. Seamed tubing can get a lenght wise crack in it or it can just not ride as well.

Seamless tubing is Drawn over Mandrell ( D.O.M ) this is suitable for building aircraft or racecar parts. Yes the good frames on the market are D.O.M tubing on all 10 tubes.

As for "double butted" it's thicker near the welded joints due to the strenght lossed during welding.

I hope this helps clear up some stuff with this frame. it's not that the bike will rust quicker. it's about quality and what you can get for your $

What is this 10th tube you speak of?


My friend has one of these bikes and it is nice! I had rode on a lot of high-end bikes (dawes sst, windsor the hour, mercier kilo tt, etc etc) and this bike is just as nice, if not nicer than all of them. Also, it offers something a lot of other bikes don't..options! The colors are awesome and really make you stand out from the pack!

Dawes, Windsor, and Mercier are now "high-end" bikes? They are all an excellent value, but certainly not "high-end". Not even sure if you could call my Wabi "high-end", although the components are far superior to those on the Republic and many BD bikes. It's also twice the price. But it has options too. You can select the stem length, bar style and width, crank length, and gear ratio. I find that to be more important than choosing wheel/tire color combinations, unless you're looking to buy a bike as a fashion accessory.

What is this 10th tube you speak of?

1. top tube
2. down tube
3. seat tube
4. head tube
5. left chainstay
6. right chainstay
7. left seatstay
8. right seatstay
9. left forkleg
10. right forkleg

Originally Posted by Brian
What is this 10th tube you speak of?

1. top tube
2. down tube
3. seat tube
4. head tube
5. left chainstay
6. right chainstay
7. left seatstay
8. right seatstay
9. left forkleg
10. right forkleg

Don't you mean "11?"

11. Steer tube

Don't you mean "11?"

11. Steer tube


1. top tube
2. down tube
3. seat tube
4. head tube
5. left chainstay
6. right chainstay
7. left seatstay
8. right seatstay
9. left forkleg
10. right forkleg

You're joking, right?

You're joking, right?
No. Why?

You fork's not much good without a steer tube. Just because you can't normally see it doesn't mean it's not necessary and shouldn't be high quality. A high quality steer tube will be butted, like a frame tube and should be a high strength alloy steel. Some companies, e.g. Columbus and Tange, further reinforced their steer tubes with internal ribs:
http://www.os2.dhs.org/~john/columbus-steertube1.jpg

Fork blades are usually considered one thing. I can see how a steer tube might be separate sometimes, though. There is such a thing as a fork made up of a chromoly steerer and hi-ten blades (at least in the BMX world).

Traditional bicycle frames have always been comprised of nine tubes.

Traditional bicycle frames have always been comprised of nine tubes.

When I buy a tube set to build a frame, it darned well better have 11 tubes as described.

When I buy a tube set to build a frame, it darned well better have 11 tubes as described.

Now we're up to eleven tubes for a frame? Since the fork is not part of a frame, I'm even more confused.

How many tubes in this frame?

135272

Now we're up to eleven tubes for a frame? Since the fork is not part of a frame, I'm even more confused.
Time was, when you built a frame you were also expected to build a fork. I'll concede that isn't always the case anymore, but first you need to enumerate the 9 tubes you think comprise a frame.

1. Top tube
2. Head tube
3. Down tube
4. Seat tube
5. BB shell
6. Left seat stay
7. Right seat stay
8. Non-drive side chain stay
9. Drive-side chain stay

1. Top tube
2. Head tube
3. Down tube
4. Seat tube
5. BB shell
6. Left seat stay
7. Right seat stay
8. Non-drive side chain stay
9. Drive-side chain stay

I don't consider this a frame tube or part of a tube set. It is often a casting provided separately and in the old days it included the lugs for the DT, ST and CSs. Maybe things have changed since then.

I don't consider this a frame tube or part of a tube set. It is often a casting provided separately and in the old days it included the lugs for the DT, ST and CSs. Maybe things have changed since then.

For as long as I can remember, frames have been described as being made up of those 9 tubes. And looking at the two fixed gear bikes in my office right now, the BB shells on both appear to be a piece of tubing.

Why don't you re-post on the Frame Building forum and see what those guys say.

I don't consider this a frame tube or part of a tube set. It is often a casting provided separately and in the old days it included the lugs for the DT, ST and CSs. Maybe things have changed since then.

For once :D Brian is right: the BB shell is definitely part of the frame tubing, and is sold as such.

For once :D Brian is right: the BB shell is definitely part of the frame tubing, and is sold as such.

Careful, you could be banned to tarck for agreeing with me.

For once :D Brian is right: the BB shell is definitely part of the frame tubing, and is sold as such.

By whom?

http://www.cycle-frames.com/bicycle-frame-tubing/TUBE-SETS/
http://www.os2.dhs.org/~john/catalogs/Columbus-tubes.pdf
http://www.os2.dhs.org/~john/catalogs/tange-catalog.pdf
http://reynoldstechnology.biz/assets/pdf/rtl_2010_parts_list.pdf
http://www.henryjames.com/ttkits.html
http://steelrenaissance.blogspot.com/2009/07/vitus-tubing-specs.html
http://www.bikeschool.com/PDF_Files/KAISEIPoster.pdf

BB shells are usually sold separately from the frame tubes.

This thread needs a kitten photo.

For as long as I can remember, frames have been described as being made up of those 9 tubes. And looking at the two fixed gear bikes in my office right now, the BB shells on both appear to be a piece of tubing.
On TIG welded frames the BB shell is simply a piece of tubing, but it is not generally supplied with the tube set you buy from Columbus, Tange, etc, but rather purchased separately.

On lugged frames the BB shell is either a bulge-formed piece with spigots to accept the set tube, down tube and chainstays or an investment casting in a similar form. In either case, the shell is sourced separately from the frame tubes themselves. The only notable exceptions I can recall are the aerodynamic tube sets sold by Columbus and Tange whose tubes would not fit a standard 3rd party BB shell.

Great thread!

On TIG welded frames the BB shell is simply a piece of tubing, but it is not generally supplied with the tube set you buy from Columbus, Tange, etc, but rather purchased separately.

On lugged frames the BB shell is either a bulge-formed piece with spigots to accept the set tube, down tube and chainstays or an investment casting in a similar form. In either case, the shell is sourced separately from the frame tubes themselves. The only notable exceptions I can recall are the aerodynamic tube sets sold by Columbus and Tange whose tubes would not fit a standard 3rd party BB shell.

But the discussion wasn't about where they come from, or what's included in a tubing set. How many tubes is a frame (not including a fork) comprised of?

troll troll toll

But the discussion wasn't about where they come from, or what's included in a tubing set. How many tubes is a frame (not including a fork) comprised of?

Then why not include the brake bridge and chainstay bridge while you're at it?

Not a great bike