What defines a "good" frame compared to a total crap one?
#1
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From: Lubbock, TX
Bikes: Masi Vincere (2011); Diamondback Interval (1993); Miyata SSCX build (c. 1990)
What defines a "good" frame compared to a total crap one?
A friend has an Al frame he's offered me. What things about a frame make it worth the build? I'm getting this for free, so no discussion about steel vs. Al vs. CF because I'm not actively looking for a frame.
What are the qualities of a good frame? Are light weight and clean welds enough since road frames pretty universally follow the diamond model? Other things worth considering? Please discuss.
What are the qualities of a good frame? Are light weight and clean welds enough since road frames pretty universally follow the diamond model? Other things worth considering? Please discuss.
#3
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It's not so much as the frame material but what the builder does with the material. Frame geometry afftects handling and comfort. Just by changing the seat and head tube angles, you can move from a sports car to a Cadilac feel. Change the chain stay lengths and you go from a rapidly accelerating feel to a loaded bus sensation. The frame tubes can be nade think or thing or the wall thickness can do the same thing - make the frame strong and stiff or more flexible and comfortable.
#4
You should have bought titanium fiber. Just kidding.
Well, it depends on what you want to do. One of the qualities of good frame is stiffness, because the more flexy a frame is, the more of your effort goes into flexing the metal instead of moving the bike forward. Conversely, a really stiff bike tends to be a little bit harsh, in the sense that every crack in the road goes into your shoulders. The geometer is also pretty important; for example, you can make a bike comfy by raising the handlebars, or fast by lowering them, putting the rider in a more aerodynamic position. A short wheel base and a high bottom bracket make for a responsive ( also known as "twitchy" ) ride.
There's really a lot going on here, and it's pretty hard to say over the interwebs. Probably the first question is whether it fits you at all?
There's really a lot going on here, and it's pretty hard to say over the interwebs. Probably the first question is whether it fits you at all?
#5
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From: Lubbock, TX
Bikes: Masi Vincere (2011); Diamondback Interval (1993); Miyata SSCX build (c. 1990)
...The geometer is also pretty important; for example, you can make a bike comfy by raising the handlebars, or fast by lowering them, putting the rider in a more aerodynamic position. A short wheel base and a high bottom bracket make for a responsive ( also known as "twitchy" ) ride.
There's really a lot going on here, and it's pretty hard to say over the interwebs. Probably the first question is whether it fits you at all?
There's really a lot going on here, and it's pretty hard to say over the interwebs. Probably the first question is whether it fits you at all?
Assuming I'll use standard 700c wheels, how can I look at the geometry? ie, what are "aggressive" head tube/seat tube angles and what are relaxed angles?
#11
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Columbus tubing preferably MAX and Bianchis Superset design. IMHO nothing rides better
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“One morning you wake up, the girl is gone, the bikes are gone, all that's left behind is a pair of old tires and a tube of tubular glue, all squeezed out"
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“One morning you wake up, the girl is gone, the bikes are gone, all that's left behind is a pair of old tires and a tube of tubular glue, all squeezed out"
Sugar "Kane" Kowalczyk
#14
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From: Prairieville, Louisiana
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#23
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Quality is about frame material, construction, detailing, and finish.
Geometry doesn't come into the equation, IMO, because even if tri-bike angles don't suit your mountain riding, the bike would have to assessed within its intended purpose.
So, sophisticated, big grade tubesets, labor intensive details like custom bits, bends, lugs, and complicated constuction need to be considered together, as do details like joint finish, cable routing and stops, and materials used for stops braze-ons and dropouts.
As mentioned above, getting a good frame is pretty easy, and you'd have to go out of your way to get total crap these days. However, getting a great frameset is another thing, and can be quite pricey.
Geometry doesn't come into the equation, IMO, because even if tri-bike angles don't suit your mountain riding, the bike would have to assessed within its intended purpose.
So, sophisticated, big grade tubesets, labor intensive details like custom bits, bends, lugs, and complicated constuction need to be considered together, as do details like joint finish, cable routing and stops, and materials used for stops braze-ons and dropouts.
As mentioned above, getting a good frame is pretty easy, and you'd have to go out of your way to get total crap these days. However, getting a great frameset is another thing, and can be quite pricey.
#24
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From: Chicago
You can measure frame geometry and visually inspect it, but the only way to measure stiffness, road feel, etc, is to build it up and ride it. After a few rides, you'll know if it's right for you. Fit is key. I'm currently riding a new, but cheap aluminum frame, and besides being a bit harsh on rougher patches of asphalt, it's great because it fits me. That's the most important thing. You can mess around with stem length and seat fore/aft positions only so much. Build it up and give it a ride. Gino
#25
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From: Lubbock, TX
Bikes: Masi Vincere (2011); Diamondback Interval (1993); Miyata SSCX build (c. 1990)







