New answers tagged

3

In the long term I think you've written off your frame. Sorry. We've figured out that this is the underside of a chainstay. Chainstays live mostly in tension while being ridden - that means you're pushing down on the middle of the bike, and the two wheels "want" to roll apart, away from each other. What you've got there is a weak point, which will ...


3

That's pretty badly gouged. Should be OK for the near term, but could fail down the road. I've wondered if, in situations like this, it wouldn't make sense to wrap the spot with sheet metal of some sort, perhaps epoxying it in place in addition to using some spiral clamps.


6

Show a bike mechanic to be sure but the frame is likely to be OK unless you like to jump a lot. Judging from plastic pedals, 9 speed or less chain, and V brakes, you probably have a relatively cheap frame which means thick straight gauge metal. You could gently file or sand the surface of the scrape flush with the rest of the tube. I’d leave it unpainted or ...


0

I've ridden scratched up frames for years with no problems and I don't see any cracks in yours, so you're likely ok, unless you're putting the frame under extreme duress on your rides.


0

Normally non standard parts should be available from the manufacturer. If they think it is "too much work" to provide spares so please buy a whole new bicycle now, this really not a good thing to know about them, while if the bicycles are dirt cheap still may be a policy. After all, you may bend that frame on the second day and still have all other ...


3

For mountain bikes, I'm not really sure there's a choice, for a new bike at least: from a quick search from some manufacturers, the offer in steel is really marginal, and most of the offering is about bikepacking bikes (niche products then, that I wouldn't recommend for a first bike). Another way to answer the question is to look at the manufacturer's ...


4

There's a lot more to unpack in the materials used for bikes. The terms steel, aluminum and alloy are all vague names that don't actually describe the material being used. "Steel" frames can either mean hi-tens steel that you'll find in big box stores or a steel alloy that you read about on mtb websites such as chromoly (chromium-molybdenum) or ...


4

I recently read that aluminum bikes are as heavy as steel bikes: Builders usually make the aluminum tubes larger and thicker to make it stronger, which adds extra weight and makes it heavier just like the steel ones. This is not generally true in my experience. A identical frame with the same stiffness will be lighter in aluminum. Steel does damp more ...


3

I think the key word here is "First mountain bike" You've not said what kind of riding you want to do - a MTB for cross country riding, or around a flat dirt path with the kids. Could be commuting on poor roads where you think you need suspension. I suggest you focus on something that costs well below your maximum budget. Whether that is steel or ...


1

Usually aluminum frames of equivalent quality are slightly lighter weight. Not much, but you can measure the weight difference. Also today, due to economies of scale, aluminum frames are usually somewhat cheaper. Sure, you could compare a butted thin-wall high-strength steel frame and the cheapest aluminum frame you can find that doesn't have butted tubes. ...


9

The modern design has one really important feature for the frame makers and sellers: They only need to stock very few different frame sizes, the rest is adjusted by selecting a suitable seat post. However, this design is a massive step backwards in terms of structural robustness of the entire bike: While the frame's strength is not reduced significantly, the ...


7

The seat stays being attached further down the seat tube increases frame compliance--essentially a little extra frame flex at the seat tube-- to help smooth road & gravel vibrations and bumps. The design also shrinks the rear triangle which actually enhances overall frame stiffness. Again, the increased compliance is at the seat tube while the smaller ...


23

Sloping top tubes started with mountain bikes, and were brought over to road bikes by Giant, following a design from Mike Burrows. Partly because a perpendicular joint between the seat tube and top tube is more efficient at transmitting loads, and partly so the manufacturer can get away with making fewer frame sizes. There really aren't that many bikes with ...


3

1966 Murray Wildcat Deluxe frame https://thecabe.com/forum/threads/1969-schwinn-sting-ray-fastback-1973-schwinn-speedster-20-1966-murray-wildcat-deluxe.45269/


2

I don't know if you're still planning on restoring that BMX, but what I can tell you is that I have that exact same bike. I have had mine since brand new and brought it in 1999. I don't think it has much value so to speak, but it's been put together to compete with Mongoose. Mine has blue chrome parts rather than the purple/pink yours has. Does your chain ...


2

Thanks guys. I scraped off the paint to the raw aluminium out of curiosity. Still not sure if it is a dent or just an optical illusion. From certain angles/ lighting, it looks like there is a slight depression; from other angles/ lighting, it looks completely flat. Running across the portion with a sharp pick to "feel" for any indentation also ...


2

Location is close to where tensile stress are strongest (i.e. where the frame must be strong), but I would not worry about such a small dent unless it is a competition frame (i.e. it may be very light because material usage have een optimized ... and therefore any excess stress will shorten the frame life). Luckily for you, that is a perfect dent: its ...


12

That is your bike's first "war wound" and should not compromise the integrity at all. It is disappointing to have a new-thing and is now no-longer showroom clean, but that's life - keep enjoying your bike. Any bike that gets used will acquire chips and scratches, scuffs and memories over time. The bike grows character as these accumulate. Just ...


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