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i noticed that small size frames have a totally flat top tube and medium and large frames have a non-flat top tube. why is that?
small size frames have different top tubes than larger sizes
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. . .to keep what some people refer to as "ugly parts" from getting uglier. . .
Generally, the front triangle (head tube, down tube, top tube) on a size small is sized in way that won't affect "stand-over" too much. Proportionately, a larger front triangle will affect the "stand-over" thus prompting the manufacturer to "kink" the top tube. . . plus, if you look at the eye-to-eye length of a shock (say 6.5") that fits nicely on a "small", it may not bolt up similarly on a "large" frame without moving the location of a mount. By manipulating the top-tube, the shock now bolts up without major changes in geometry and, consequently, overall performance (between a "small" and "large").
Generally, the front triangle (head tube, down tube, top tube) on a size small is sized in way that won't affect "stand-over" too much. Proportionately, a larger front triangle will affect the "stand-over" thus prompting the manufacturer to "kink" the top tube. . . plus, if you look at the eye-to-eye length of a shock (say 6.5") that fits nicely on a "small", it may not bolt up similarly on a "large" frame without moving the location of a mount. By manipulating the top-tube, the shock now bolts up without major changes in geometry and, consequently, overall performance (between a "small" and "large").
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. . .yeah, in this case I'd have to say it's more to keep the "ugly parts from getting uglier. . ." A lot of trials-bikes have kinked top-tubes too.
Nice shot Dogonfr. . . track looks like fun. . . wait a minute, you sure that TT's bent? Could be the tube's straight and just looks crooked; I mean, look at that fence. . . you sure that wasn't taken with a "fish-eye" lens?
It's got "wall-ride" written all over it!
Nice shot Dogonfr. . . track looks like fun. . . wait a minute, you sure that TT's bent? Could be the tube's straight and just looks crooked; I mean, look at that fence. . . you sure that wasn't taken with a "fish-eye" lens?
It's got "wall-ride" written all over it!
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:lol::lol: Funny I was thinking about supporting that section to handle a WallRide. :cornut::rockon:emptybe_er said:. . .yeah, in this case I'd have to say it's more to keep the "ugly parts from getting uglier. . ." A lot of trials-bikes have kinked top-tubes too.
Nice shot Dogonfr. . . track looks like fun. . . wait a minute, you sure that TT's bent? Could be the tube's straight and just looks crooked; I mean, look at that fence. . . you sure that wasn't taken with a "fish-eye" lens?
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My black 575 is small, the turq is a med. Both with bent top tubes. The TT design varies a bit between the two as the black is an '08 model. The stand-over height on the 575's is the same on the small, med, large and x-large frames.
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