Bicycle frame construction, selection, maintenance, and repair.

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26
votes
6answers
18k views

Why is carbon fiber inherently weak? Or is it?

This question got me to thinking: If it were possible for me to use a carbon frame, I would, but the expense and my riding style keep me using steel and aluminum. (I like hauling stuff on racks and ...
20
votes
4answers
8k views

How can you recognise a quality steel frame?

I'm looking to buy/build a road bike and I would like it to: last 100 years have a low environmental cost As I'm not interested in shedding grams (a diet would be more helpful for me), I'm leaning ...
17
votes
3answers
20k views

DIY Painting a Bike Frame: Is it possible?

I have painted a couple bike frames (think really cheap garage-find rebuilds) with varying degrees of failure. Can you help me correct/fill in the missing pieces of my frame painting process? ...
17
votes
1answer
9k views

Road bike carbon fiber frame life span

I have read in several places that the carbon fiber has a shorter life span than the aluminium, and i was wondering just what would it be. I am not referring to accident related failures of the ...
15
votes
4answers
979 views

Why the penny-farthing?

The penny-farthing was the standard until the diamond-frame "safety bike" was "invented" and revolutionalized the world of bikes. It seems to me strange to have to "invent" to put the same size of ...
15
votes
3answers
9k views

Explaining the effects of frame geometries

I asked about buying a bike here, and someone asked on my behalf about test-riding a bike before buying. My question is, what should I know, or should have known, about the sizing or 'geometry' of a ...
14
votes
9answers
6k views

How does a bike's weight affect the overall experience of owning it?

Naturally, carrying a light bike up the stairs is much more enjoyable compared to a heavier bike. Are there any other aspects of a bike which are affected by its weight? For example, would the weight ...
14
votes
2answers
2k views

Bamboo bikes - the verdict?

I'm curiously interested in buying a bamboo bike for use as a Sunday road bike, and I'm just wondering whether they're suitable: Strength at high speed? I live near Parbold, which has nice hill ...
14
votes
2answers
2k views

Dealing with rust on a steel frame

I have a small spot of rust on the bottom side of my steel frame's top tube (Columbus Niobium tubing). It's from abrasion during transport that I didn't notice until it was too late. The spot is ...
13
votes
8answers
4k views

Removing Seat Post rusted into downtube

I have an old steel frame (Columbus Number 2 I think) that has the seat post (Suntour Superbe Pro - see, I said it was old!) rusted in. I have tried lots of WD-40 but it will not budge. Any tips on ...
13
votes
5answers
912 views

Why is it common for cheap bikes to have the frame sawn in half below the saddle?

These days cheap bikes often seem to come with the frame sawn in half below the saddle. What does the manufacturer gain from this design, and why is it associated mostly with cheap, low quality ...
13
votes
5answers
4k views

Rear wheel slipping out under load

My commuting/cyclocross bike (a Surly Crosscheck) has a problem. If I tighten the quick release skewer to a normal level, sort of firm to close it, then if I step on the pedals hard at some point, ...
13
votes
6answers
2k views

I keep breaking my road frames - why?

I've gone through four frames in the last decade or so, all from different manufacturers, all steel but both lugged and welded. Every one of them has eventually developed a crack, been repaired and ...
13
votes
3answers
5k views

Repairing a bent bike frame, is it worth it?

I have a bike with an incredibly bent frame. The bike itself I have tried to replace with other inexpensive bixes, but this one just had a certain geometry that I keep wanting to resurrect it. It is ...
13
votes
3answers
5k views

How do I measure the size of my bicycle frame?

From what point to where do I start measuring? I suspect the bike I'm trying to measure is a 56cm because I usually ride a 54 and this is slightly too big, but I want to be sure.
13
votes
2answers
731 views

How to prepare a frame for a new paintjob

I want to have my bike frame repainted. What should I do before I give it to the paint shop? How would they like to have it prepared?
12
votes
5answers
1k views

Should my foot be able to step flat on the ground, when I sit on a bike seat?

I was wondering, for a correctly sized mountain bike, or hybrid, should I be able to place my foot flat on the ground, when I sit on the bike seat?
12
votes
7answers
4k views

Is there such a thing as frame failure?

Several general questions have been asked regarding how long a bike or bike frame will "last", and the gist of answers seems to be that a bike can last quite a while of the replaceable components are ...
11
votes
3answers
2k views

What are the advantages of investment casting?

I'm starting to see more and more frames using investment casting for head tubes, drop outs, seat tubes, etc. Such as the new WTP c.r.e.a.m. frame . It looks nice, but I'm suspect on how much more ...
11
votes
2answers
298 views

What is the difference between a horizontal top tube and a sloped one?

Some comparable bicycles have a crossbar (top tube) that's horizontal: Others have one that's sloped: What are the reasons for either frame design? Is it merely style preferences? Or is there ...
11
votes
0answers
1k views

Name that frame! (Likely Japanese, likely made in 1986, with known serial number, likely a Bianchi)

(This post was substanically edited/updated on 5/8/14.) I have a bike frame of unknown lineage. What is known: The serial number under the bottom bracket is IS513786. This fits with the serial ...
10
votes
2answers
3k views

Is it possible to repair a dent on an aluminium frame?

I have Centurion Cyclo Cross 4000 bike. Recently I got into an accident with a car door. As a result I have a significant dent on my frame(see the photos below). I have two questions: Is it ...
9
votes
8answers
15k views

What are the differences between a mens and womens bike frame?

Why do women's bikes have a diagonal bar in the frame instead of a horizontal frame? Is this the only difference? Sorry if this has been asked (but I cannot find it by searching) and I also just ...
9
votes
3answers
360 views

Why do some triathlon seatposts go straight up and down instead of at an angle?

Why is it that some triathlon bikes have a seat post that adjusts straight up and down instead of the more standard axis that aims at the bottom bracket? This means that if you raise (or lower) the ...
9
votes
4answers
3k views

Why would a bike feature a “carbon wrapped aluminum frame”?

I saw a link to what appeared to be a Carbon bike on amazon. The price was extremely lower than any carbon bike I had ever seen. After reading a bit, it seems that the bike frame is really made of ...
9
votes
3answers
921 views

Should or can I (car) wax my frame?

Having spent the whole summer taking a bike apart, painting it and now in the process of building it again, I was thinking about waxing it. I want the finish to last as long as possible, after all, ...
8
votes
7answers
17k views

What are the advantages and disadvantages of riding a smaller Mountain Bike frame?

I am 182cm (5' 11'') tall and am looking into buying a new frame for my mountain bike. Right now i have a 19'' frame and i found a good deal on a 17'' frame. The guy from the shop told me that it ...
8
votes
3answers
823 views

Is there any difference between professionally painting a car and a bike frame?

I'm getting ready to purchase a new bike which I love but I hate the color scheme. I can't find any custom bike paint shops in the area. Can I simply take it to a car paint shop and get a ...
8
votes
3answers
469 views

non-steel frames and longevity

Until recently, I had a late 80's Schwinn aluminum frame bike (now a thief has a 80's Schwinn aluminum frame bike, but that's another story). I had heard a number of horror stories about early ...
8
votes
1answer
460 views

What's the definition of a Mixte?

What makes a mixte frame? Further, what's the etymology of 'mixte'?
8
votes
1answer
365 views

Bamboo Bike Frames

I've seen some bamboo bike frames out there in the world. I am curious as to how they ride? Is it similar to a steel, aluminum, or carbon fiber frame? Do you think it's worth the effort to build one ...
8
votes
1answer
298 views

Help please to identify my Tandem

I have just purchased an old tandem, but don't know the make or year. Can anyone help me to identify it. The frame is steel and it has a frame number of 452599. There are no decals fitted but I attach ...
7
votes
4answers
5k views

What should a big guy look for when buying a road bike?

I'm 6ft 4" (1.8m) and 22st (139kg). I do a fair bit of cycling, mainly spinning and mountain biking. I would like to get into road riding so I'm looking to buy a road bike. I want to spend between ...
7
votes
4answers
8k views

How can I tell if a bike is too big for me?

Today I disassembled my current fixed-gear, and reassembled all the parts in another frame, which I am considering to purchase. The current owner of the frame warned me that it might be too big for ...
7
votes
2answers
264 views

How many years an aluminium frame lasts in a touring bike?

How long does an aluminium frame lasts in a touring bike? [Removed extra questions to be clear.] Background So far I preferred aluminium vs. steel for many reasons, but if steel lasts ...
7
votes
2answers
1k views

What should I consider when choosing a bike frame?

In thinking about building a road bike from scratch, what should I consider when choosing a frame? I'll be building from all new components and plan on just doing day rides of a few hours a piece, ...
7
votes
3answers
981 views

How to match a paint color?

Do you know how to match a color on the frame ? I want to buy a paint from a tool shop but I'm not sure if it's match with the frame color. I'm going to use the paint for a touch up. Thanks for the ...
7
votes
2answers
2k views

Why offset the rear rim to the hub and not the hub in the frame?

I'm currently reading The Bicycle Wheel by Jobst Brandt, and I'm reading all of the issues with offsetting the rear rim toward the drive side of the hub... Asymmetry in a rear wheel built for a ...
7
votes
3answers
1k views

Should I Get the Paint Job Touched Up

My wife's bike recently got scraped up and the paint got scratched down to the frame. It's an alloy frame. Should she be concerned about rust or any kind of damage? If so, do we need to get it ...
7
votes
2answers
513 views

Do I need to plug internal cable routing ports?

I have just ordered a OneUp Components 42T sprocket and a Race Face 30T Narrow/Wide single ring so that I can convert my 3x10 drive train into a 1x10. This means that I'll be removing the front ...
6
votes
5answers
3k views

Which type of frame is better for a touring bike, steel or aluminium?

I hear that a steel frame is more comfortable to ride for a long tour but that it is heavier and easier to rust than aluminum. Which material is better for a touring frame?
6
votes
5answers
690 views

High-quality commuting bike with “women's” frame

My wife wants a high-quality commuting bike (riding almost an hour each way five days a week). However, she wants it to be compatible with skirt-wearing and, as a result, refuses to have a frame with ...
6
votes
3answers
3k views

Why are steel bikes more expensive than aluminum?

It's hard to find a chrome moly bike for less than $1000 these days. Is it because it's actually less expensive to manufacture aluminum bikes these days or is the market for chrome moly bikes so ...
6
votes
3answers
825 views

Is my derailleur hanger too bent?

I bent the derailleur hanger on my 9spd cassetted Bianchi Volpe about 1.5 yrs ago, and I just did it again, but worse. This time the derailleur got sucked into the wheel and really did a doozy with ...
6
votes
2answers
2k views

MIG Welds vs Brazing for simple bike hacks

Given that frames are generally brazed, not welded and given that MIG welding will work on simple bike hacks what are the downsides of MIG welding these hacks? For example, I would like to make a ...
6
votes
2answers
676 views

Switching Parts to a New Frame

What things do I have to consider when planning to switch parts from one frame (old one) to another frame (new one)? Will all the parts transfer? What items may need replacement because they won't ...
6
votes
2answers
698 views

How to choose between a race bike like a Madone and a classics bike like a Domane

I ride regularly for exercise in New York City but do not race. I currently ride on a steel frame that handles the rough roads easily. I want to buy a carbon bike and am torn between a "classics" bike ...
6
votes
2answers
168 views

difference between rack mounts and fender mounts?

is there a specific way that bike builders build mounts/eyelets for racks for panniers and eyelets that hold fenders? I'm specifically thinking about eyelets on the rear dropouts. I know that if a ...
5
votes
2answers
796 views

Is it possible to compensate a short sized frame by adjusting seatpost and stem?

Could you achieve the same position you would have on a bigger frame by raising seatpost and stem? And how could I adjust those to "simulate" a bigger sized frame?
5
votes
4answers
1k views

Why aren't sportive' 'bikes popular outside the UK?

I recently bought a 'sportive' bike, i.e. very much like a road bike but with a taller head tube to give a slightly more upright, more relaxed, less 'heads-down' riding position, and a triple chainset ...