Entry level road bike alum frames

Of the entry level road bikes, who offers the stiffest frame with minimal BB flex?

The CHEAPEST will probably be the least engineered, and therefore the stiffest because excess material will probably be used to ensure frame strength.

A smaller frame size will be stiffer if all other things are equal ...

A "compact" frame will be slightly stiffer than a frame with a horizontal top tube if all other things are equal (including, the "virtual" top tube length of the "compact" frame & actual top tube of the "standard" frame).

If you're aiming for a bike from your LBS, find two with comparable components, and buy the heavier of the two ... it should have the stiffer frame.

There is absolutely no basis for either of these assumptions.

Pssst, don't tell anyone, but most entry level frames regardless of labels are all made by the same factory in Taiwan......

ABSOLUTELY. Hence, the logic of presuming the heavier of two comparably equipped bikes will have a frame with more raw material (vs. paint & decals) ... more of the SAME material means greater stiffness for a comparable configuration. QED?!?

But it doesn't. Suppose that both bikes are using the same tube set. Being made in the same factory means that the welds are the same. The only thing that can make one frame heavier than the other is if one of them has longer tubes somewhere. That bike is inherently going to be more flexible. Now, suppose both bikes are not using the same tube set. One of them may have a smaller OD and thicker walls, once again raising the possibility that the heavier bike is more flexible. You might as well just insist that whichever frame is painted red is the stiffest.

Quiet now. You're not supposed to notice the "Made in Taiwan" underneath the American flag sticker.

You are presuming the same tube set (which may be more than likely the case), and I am suggesting a different tube set may be used in two different frames which may otherwise appear to be comparable.

Has anyone used small tubes in an aluminum bike frame in the past 12 years?

HEY!?! Do they even paint bikes red in Taiwan? If they did, they would no doubt make those stiffer so that they would have a worse ride!

You know, the original question was sort of silly (no offense to the poster, SD2006) ... I don't think he wanted a sophisticated answer ... and, I don't think he was planning on measuring the tube OR observing differences in how the tubes may-or-may not have been shaped (i.e., what I alluded to as being "engineered").



For the benefit of apparently anal-retentive-minded artmichalek, & bretheren, for whom absolute precision is requisite for responses by other than themselves:

Allowing that the two frames are identically spec'd by the designing engineer, and presuming that the frames are properly tempered after welding, the heavier one will have heavier welds and will undoubtedly be infinitesimally stiffer BECAUSE it has more material at the welds and/or more paint.

Here's an idea. Why not ride them and see which one feels better. Then get the other one. It will be stiffer!!!

L

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Pick any Two.

Well now you've gone and ruined it for everyone, throwing a thing like common sense into a perfectly ridiculous debate. I hope you're happy.

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Felt F80...

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George.

Merida 901

Thanks to those who provided an honest attempt to entertain my newbie question.

I've decided not to buy. After riding my friend's Trek 1200 I suddenly realize how roadworthy my old mtn bike is. I would have to spend a ridiculous amount of money to get something that's noticeably better than what I've already got.

Wow, "tempering after welding" .... That's a really interesting concept. I am absolutely positive that everyone in this forum would like to hear, in detail, how "tempering after welding" is accomplished. Please include some links to reputable technical resources. That way we will all know that you are not just making this stuff up as you go. And you want people to believe you are credible, right?

Actually, what I really want to hear is what you have to say about forged frames and "proper tempering" of such.

AND, there you have it -- yet another anal-retentive-mind makes itself known.

Did you want me to explain how the modulus of elasticity is affected by high temperatures ... or, how the tensile strength of the alloy is changed ... just what did you want to know?

Did you want to know about molecular changes?

Do you know what tempering is? Or, is it just that when you suck on your thumb that you become hypoxic to the point where you ask stupid questions?