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12

It is very likely that you are putting too much stress on the frame when you are cycling due to your power stroke. It took me a long time to train myself to avoid standing and powering the bike through the acceleration of starts, or even powering through it while sitting. I've long since learned that while I have plenty of power, I actually am able to ...


10

There are certainly techniques that will put unusual strains on the bike, track stands could be, I certainly think that excess use of a turbo trainer does. I (try) to do track stands where possible and my commute bike (~150k per week for a number of years) only died when I crashed it ... Quality of the ingredients is certainly one factor. Another could be ...


9

If you look at titanium frame bikes on the web you can see their warranties. Most have very long or life time warranties that cover everything but crashes and deliberate damage to the frame. So I would assume this frame was involved in a crash. There are three types or cracks in titanium frames (from best to worst): Weld crack seam crack (titanium comes ...


8

I had a run of bad luck with road frames quite a few years ago, going through about three in rapid succession. Like you, the faults were always in different places. Since then I haven't had any troubles, but I did start using a slightly higher upgrade of frame materials. I currently ride about 120K a week,mainly commuting, doing track stands wherever ...


6

I am going to get beat up for this but steel frames don't fail catastrophically. Pull that post. If the end of the post is in the middle of the crack then look for a longer post. Get a seat post that extends at least 2" below the bottom of the crack and ideally 4". The post reinforces the frame. Mark the two ends of the crack. If the crack grows ...


6

It's hard to tell from the photo ( is that large vertical streak said crack? ), but if your frame is cracked, don't use it. Riding on a cracked frame is risky as it could result in a catastrophic failure / injury / death. It looks like that's probably a steel frame, so find a local frame builder ( not your buddy who's handy with a welder ), and depending on ...


5

The crack is in the bottom bracket(BB) axle. This will at least need to be replaced. If the crank arm(silver part) is not damaged this can be reused. There are many types of bottom bracket standards but it is most likely this frame has a 68mm English thread square taper bottom bracket which are the most common in pre year 2000 bikes. Something like a ...


5

I think this question has gone a while without an answer because it's a little unclear what you want to do... do you want to do it yourself? Or by 'experience with welding' do you mean 'experience with having welded'? Either way, I don't have an answer for you, because I don't have direct experience welding titanium, nor do I know any welders in NJ, but I ...


5

Am I looking at the right thing? The little line running across the seat tube about 1cm above the bottom bracket? It's hard to say, but personally I'm not sure that's a crack at all. It looks more like a scratch. I say that because: a) it looks shallow, and b) that is a really, really weird place for a crack to occur. There are four types of stress ...


4

The cracks will expose the internal structure to elements. So yes, they are not going to last as long as non-cracked ones but very probably not going to explode right away either. The Nokia tires that used to be popular in my country developed cracks between tread and sidewall after a few months' use and could still be ridden for years afterwards. Your ...


3

Honestly, how much did this bike cost? It looks to be at least 30 years old, judging by the tire and brakes we see in this picture, and even when it was new, I doubt it was worth repairing this kind of damage. The cost of repairing it would be far in excess of buying a new bike. Now, if you'd spent $1500 on it, even 30 years ago, well, maybe it's worth it. ...


3

It looks like plain old metal fatigue. Most probably there was a hairline crack, then water got into it and rusted it out. Note that when you extend the seat height, you increase the lever arm of the seat post and put a considerable amount of stress on the frame precisely at that location. It doesn't help that the design of that seat clamp has no ...


3

I broke two steel frames in different ways, but both were used for commuting under heavy loads. I stretched the rear dropouts of a frame built for a 7 speed hub to fit a 9 speed hub, and this put stress on the chain stays just behind the rear bottom bracket. After about 6 months of daily riding, the right chain stay cracked. I rode my bike head on and it ...


3

Riding without enough seat post in the bike is a real problem. Not only do you increase the mechanical advantage of the seat post against the seat tube but you put stress where the bike was probably not designed to take stress. And you are putting stress in the area of the top tube and seat stay. You state you have been riding with a longer post. Have ...


2

As an avid cyclist and every day NYC bike commuter, I had a similar problem with road frames. Aluminum frames would last about 9-12 months and steel TIG welded frames generally lasted about 18-24 months before cracking at the bottom bracket (full disclosure, I'm 6'1" and 210 with all my gear). Alas, there is a solution, with the advent of twenty-niner ...


2

Generally, if fairly new tires start to crack, they were poor quality tires to begin with. That's a red flag on its own. Don't use them. Bicycles only have two tires between you and the ground, that means if your only front tire fails at speed the chances are good that you're going to end up on the ground. Without a definitive image of the damage, damaged ...


2

I would not ride that bike, as pictured. How to fix it? I shattered a cup on my old MTB. The fix was to take the bottom axle into a bike shop and they couldn't supply the right part, so I bought a sealed cartridge instead. It went in easily, needs no bearing tweaking, is waterproof and brilliant. Only downside is you'll need these tools: 14 mm socket ...


2

Dawes Galaxy? Looks like an older model - so a good quality touring frameset - possibly Reynolds tubing. Anyway, what price do you put on sentimentality? I'm not sure where the idea of long seatpost comes from as the picture doesn't show it. But if you are UK based a company like Argos cycles can easily fix that frame for you. Its a welding job - so the ...


1

If you're replacing the BB yourself, just make sure you get the right one. You need to consider the following variables: General type (we already know it's a square taper, so no problem there). The width of the shell (the painted part) - that's easy enough to measure. The length of the spindle (axle) - you'll have to remove the cranks to get an accurate ...


1

The problem is liability. Any shop is likely to tell replace as they don't want the liability of it breaking and you getting hurt. Plus they want to sell you new frame. I would go with your team mate the mechanic. See if it grows. Even if it does fracture and you fall I bet it will not be your first fall nor fatal.


1

A couple of years ago we had a new seat tube fitted to my wifes bike (a 20 year old Claud Butler Lady Dale) after it sheared where it joined the top tube - this was on a step through frame. Fortunately we live close enough to Roberts, one of the few frame builders in the UK, to be able to deliver it. I had to strip the frame for them and it cost about £150. ...


1

You're better off getting on the phone to FSA as opposed to asking your questions here. If it's a common problem they'll be the ones to know and they'll likely be eager to set it right. I can tell you that I've had no such problems with my Gossamer cranks in many years of ownership. If I were to speculate I would say that that is a defect and if the cranks ...



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