Bicycle frame construction, selection, maintenance, and repair.

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7
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4answers
611 views

To Cold Set or Not To Cold Set?

I have a Trek 620 (Reynolds 531 lugged steel frame) from the mid-80s the rear dropouts are spaced at 126 mm. I'd like to be able to run an 8- or 9-speed cassette and I was wondering about the issues ...
7
votes
3answers
2k 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
138 views

What's this cotter pin on the barrel adjuster for?

I bought a new Salsa Colossal frame to build up and it has a cotter pin on the frame mounted barrel adjuster: If I turn the barrel adjuster too much, it is going to start digging in to the ...
7
votes
2answers
604 views

How bad is this fire damaged alloy frame?

I got this Shimano Ultra groupset bike for free, all I need now for it is shifters as the carbon and rubber melted in them and the original seat. But now I am wondering if I can get away with it, I ...
6
votes
5answers
8k 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
3answers
7k 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
8k 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
5answers
41k views

How to tell if a carbon frame is damaged or if the paint just has stress cracks

I am looking at a carbon framed road bikethat has me concerned.On the topside of the bottom bracket,drive side there is a very small hairline crack in the paint.The seller states that it has been ...
6
votes
1answer
423 views

3D printing frames?

Are there any technical limitations that make 3D printing frames impractical? And, if it is just a matter of time before our technology is able to overcome any limitations (like manufacturing ...
6
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4answers
294 views

Alternative uses for an aluminum MTB frame

Any alternative use for old mountain bike tyres and inner tube? So my frame has a large crack near the headtube and I am replacing it. Could I use the frame in any other way? E.g. give it away ...
6
votes
1answer
339 views

S shaped down tube (MTB)

Are there any advantages of S shaped down tubes over the traditional ones on MTB? For example: what do you think of this design? Jamis Exile Comp 2013
6
votes
2answers
948 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
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 ...
6
votes
2answers
166 views

Should I worry about rain getting inside my frame?

I commute to work every day and lock my bike on the street. I have a nice saddle so I remove my seat post and take it into work with me. This obviously leaves a hole open to the inside of the ...
6
votes
1answer
7k views

How much does non-ideal frame size matter?

I have an opportunity to buy a barely-used Allez Elite for a very small amount of money (around $100). However, its frame size may be slightly different than the "ideal" size for me. If this ...
6
votes
3answers
6k views

Metal seat post with carbon fiber frame?

Is using a metal seat post on a carbon fiber frame advisable or not? I want to use a seat post mounted rack on my road bike (no regular rack mount points are on this bike), but I have been told that ...
6
votes
2answers
93 views

Lugged carbon frame repair

In broad terms, I'm wondering if it is possible to repair a high quality lugged carbon frame, say a Colnago C60, that has been cracked in the top and/or down-tube. Normally once a carbon frame has a ...
6
votes
4answers
152 views

Fracture in folding frame - safe to ride?

I cycle every day because I live in a city and I find it a fun, fit and convenient mode of transport. I am not a cycling hobbyist, am only averagely fit and know pretty much nothing about bike ...
5
votes
4answers
627 views

Advantages of mounting bottle under frame

I'm wondering if there are any advantages to mounting ones water-bottle on the bottom of the down tube, near the ground, versus on top of the tube. I'm mainly interested in the advantages, or lack ...
5
votes
5answers
2k views

What can I do about a cracked frame?

I noticed the other day that my frame has a crack in it! I believe that it's my seat post causing the problem. A couple of questions really, a) how serious is this? and b) can it be repaired? Edit: ...
5
votes
2answers
29k views

Building my own full suspension MTB: How to I select a frame?

I've recently gotten back into mountain biking. I took my 5 year old Iron Horse full suspension out to the mountain with some friends that had recently purchased new bikes. I haven't ridden for a ...
5
votes
3answers
992 views

Cable routing and why is there no optimum solution

This is a general question, regarding the routing of the cables of both brakes and derailleurs on a frame. I find it highly practical to mount all cables along the bottom of the top tube. This ...
5
votes
2answers
7k 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
3answers
3k views

26“ vs 28” wheels for touring

I was told by a friend that 26" wheels are better than 28" wheels for touring. Is this true? What are the pro's and con's? I'm told that 26" wheels are stronger for their spoke count. What are the ...
5
votes
3answers
9k views

Attach bottle cage to frame w/o mount screws

I'm planning on getting a bottle cage for my bike, but my bike does not have the standard mount screws for one. As I understand it, there are two types of cages: bolted cages and clamped cages. I'd ...
5
votes
4answers
427 views

What is this brown goop on my new bike frame?

I'm building a single speed bike, and ordered parts from various different places. My EAI Bareknuckle frame got delivered this morning, and it looks great, except for this part of the fork, that has ...
5
votes
2answers
2k views

Why don't frame manufacturers ream/face their frames?

Before building up a new frame, it's crucially important to ream/face the headtube and crown race seat (and the bottom bracket, if using press-fit cups). You should also ideally chase the threads of ...
5
votes
6answers
5k views

Fixie/Single speed frame information for beginner

I don't want to buy a ready made bike because singlespeed or fixed gear bikes are way expensive due to their popularity. I want to make my own bike, I haven't build a bike from scratch before. I want ...
5
votes
5answers
357 views

How to estimate price of an old CrMo frame?

So it happened. My old good CrMo friend got hit by a car and the blow was heavy enough to affect the whole frame. Now the car driver is expected to pay back the expenses but I am not sure how to ...
5
votes
2answers
2k views

Is torque relevant for steel/aluminium? Where do I find torque specs?

When you are not dealing with carbon, is torque relevant? I've never seen it mentioned on the hundreds of answers here, or the hundreds of how-tos I've read elsewhere. Should I just tighten ...
5
votes
2answers
169 views

How to stop the corrosion?

I have a silly question maybe.. How to protect the frame of my bike from corrosion? The bike is not new. Are there any accessories? Thanks
5
votes
3answers
506 views

Size question. Performance v Comfort

I was checking some bikes on Decathlon (a large sports orientated chain store) and I found this size guide for some of their BTwin bikes. On their chart [pdf] that maps rider measurements to bike ...
5
votes
5answers
1k views

I need help to identify this bike

This is my mother in law's bicycle from when she was a child. While cleaning out a lean-to on the back forty I found this bike inside. I was hoping to give her a bike that is identical to hers that ...
5
votes
1answer
2k views

How feasible is it to transfer modern (2010) components to a 90s frame (road bike)

My 2010 aluminum frame may be toast (stripped bottom bracket) and I was considering getting an older chro-mo frame and transferring the components to it. It's a racing/sport style with drop bars and ...
5
votes
1answer
583 views

Repairing Carbon / Aluminum frame

My road bike is aluminum with a carbon rear triangle. The carbon rear slides into the aluminum, and I believe was bonded with some sort of epoxy. The pieces have begun to separate after 2.5 years ...
5
votes
1answer
1k views

What is the significance of rear travel of a frame?

Every suspension frame has the the following two parameters: shock travel and rear axle travel at maximum shock compression. I have a lot of questions, regarding those two: What are they properly ...
5
votes
2answers
2k views

Is there much of a difference between flatland and park/street frames?

I am a newbie at biking, and I've been wanting to get into BMX for a few years, and I can now since I actually have some money. Primarily I've been wanting a 20" BMX bike with front and rear brakes ...
5
votes
1answer
505 views

Cyclocross bike frame considerations

I'm considering putting together a cyclocross type bike together for fun and variety. Is a typical road frame suitable for this? And, what do I need to consider in terms of sizing? On sizing, it ...
5
votes
1answer
1k views

Experience with welding Titanium frame?

My Litespeed Tachyon, a 1996 model, of which I am the second owner, (So Litespeed will not honour the warranty) has now developed its 3rd crack. First was in the seat tube above the deraullier and I ...
5
votes
1answer
340 views

how to strip the paint from a bike yourself?

How can I strip the paint from a bike frame? I tried using a sander and it left really annoying scratch marks on the frame. Is it possible to use a chemical paint stripper to completely remove the ...
5
votes
1answer
127 views

How is a frame designed for an easy step-thru?

My question is very specific towards bikes which have a curved top-tube. How is it decided that a particular height of the top tube above the ground for a set of people in a certain height range is ...
5
votes
1answer
461 views

Strange logo on the frame

I just bought this bike, but it seems like the frame is not Bianchi, all marks and texts are stickers. Also, there are quite a few logos on the frame. Does anyone know which frame this is? Thanks! ...
5
votes
1answer
587 views

What bike do I have?

I have recently purchased a bicycle from a second hand shop. It seems to have all sorts of different parts. The frame however has a badge and markings of 'Kontroll' made in West Germany. Doing some ...
5
votes
1answer
486 views

What tools are required to begin building a frame?

What tools are required to begin building a frame? Are there DIY substitutes for any of them? Are there things that aren't requirements, but simplify the process enough to be worth the cost? Aside ...
4
votes
2answers
1k views

Why are bike frames getting so much bigger

This is just a general interest kind of question, but I've really been wondering about this lately. We've had a lot of advancements in bikes over the years, and people are always trying to make them ...
4
votes
3answers
869 views

optimum frame size for very small 5'2" female

I have a lady friend who's interested in getting into road cycling. The smallest frame sizes I've seen so far in the market are 48 and, in one instance, a 47. Is this about the most common and/or ...
4
votes
4answers
2k views

Titanium frame has a crack - advice needed

I've found a Titanium bike frame on eBay. It's very cheap and the owner says that it has a very small crack on the seat tube where it connects to a bottom bracket. See at the image below: I've ...
4
votes
2answers
125 views

I bought a used 20 inch bmx bike from bike shop but no one has any idea of the brand

Could someone help me narrow this down? I bought a new-used bike from local bike shop in Sacramento, California, USA. I do not know what brand it is and so were the bike shop. There are no stickers ...
4
votes
4answers
382 views

What is the purpose of a serial number?

It seems like pretty much everywhere I look, serial numbers can't do the things that it seems they should be able to do. They can't help people figure out what bike they have. They can't help at all ...
4
votes
3answers
2k views

Convert old road bike to comfortable commuter

I have an rather old road bike, that I'd like to convert to a comfortable commuting bike. The bike should be used for everyday commuting (< 5km) and occasionally day tours. I'd like to keep the old ...