Is this good?

[Bonj Hovi]

That's the worst limerick I've ever seen. It doesn't rhyme properly and (cardinal sin for a limerick) it doesn't scan.

Deliberately poorly constructed like much of Bonj's advice only his isn't deliberate.

 

[Rhythm Thief]

Deliberately poorly constructed like much of Bonj's advice only his isn't deliberate.

It's still crap.

 

[Abitrary]

I think it's quite romantic.

 

[snorri]

Anyone hear if Kathy is back from John O' Groats yet:?:

 

[Abitrary]

Anyone hear if Kathy is back from John O' Groats yet:?:

She's probably emigrated there to get as far away from the internet as possible after reading all this...

 

[bonj2]

Bonj. Why do you have to be such a fool?

Please point out what was incorrect in my posting and state what knowledge and professional qualifications you have to back this up?

If you are interested I can tell you what qualifications I have in this field but I dare say you will just accuse me of making them up as is your normal method.

what's incorrect in your posting is that you're trying to make out aluminium will ALWAYS eventually fail due to flexing, but since aluminium bikes have tubes that are fat enough not to exhibit any significant flex, they never really suffer any fatigue BECAUSE of the fact that they DON'T flex. Fatigue can only occur with movement and repeated compression and stretching, over and over again. Like bending a paper clip till it breaks.
IF an aluminium bike was made out of thinner tubes, then it would flex and would fail, in a way that steel might not - but you're trying to equate a 'what if' with realilty. Aluminium might be weaker than steel for the same dimensions, but it's NOT generally made into bikes using the same dimensions as steel bikes.

 

[Abitrary]

I always wonder about the geometry.

For example, you see lots of compact alu frames, because the smaller triangles I guess compliment the stiffness of the aluminium tubing.

With steel, I imagine that with traditional geometries work better, because the flexibility of the steel works better with longer tubes.

What I don't understand is steel compact frames, like on the higher end Dawes Galaxies. Surely this compromises the ride quality of the steel in these bikes?

 

[Bonj Hovi]

what's incorrect in your posting is that you're trying to make out aluminium will ALWAYS eventually fail due to flexing, but since aluminium bikes have tubes that are fat enough not to exhibit any significant flex, they never really suffer any fatigue BECAUSE of the fact that they DON'T flex. Fatigue can only occur with movement and repeated compression and stretching, over and over again. Like bending a paper clip till it breaks.
IF an aluminium bike was made out of thinner tubes, then it would flex and would fail, in a way that steel might not - but you're trying to equate a 'what if' with realilty. Aluminium might be weaker than steel for the same dimensions, but it's NOT generally made into bikes using the same dimensions as steel bikes.

Oh Bonj,

As ever the idiot (sans savant).

Aluminium framed bikes have to have fat tubes to overcome the the inherent weakness of the mechanical properties of aluminium i.e. it work hardens then fails if it flexes. They don't readily fall apart because they have to be designed not to flex to overcome the propensity of aluminium to fail after a finite number of stress cycles.

Your selection of a paper clip as an example is one of the least appropriate to demonstrate fatigue because the metal is stretched way beyond its elastic limit and outside of the design parameters of the device. I'm not aware of any paperclip failing when used appropriately. In a bike frame steel does not get stretched anywhere near its elastic limit and therefore flexing can be accommodated.

No one has been trying to sell the idea of aluminium frames in the same tube sizes of steel frames. They have merely pointed out that I can not be done without failure being an inevitable consequence.

Bonj, if you do infact have a degree is it a B.Sc. - Bonj's stupid comments?

Your brain is not fit for purpose. Trade it in for cretin's to up the quality of your arguments.

 

[Tony]

Is your bike made out of aluminium, Bonj? Pure aluminium?

 

[Bonj Hovi]

I always wonder about the geometry.

For example, you see lots of compact alu frames, because the smaller triangles I guess compliment the stiffness of the aluminium tubing.

Not to compliment the stiffness but to enhance the stiffness. Less flexing means longer life before failure not that many aluminium frames bikes get ridden long enough to reach the point of failure.

With steel, I imagine that with traditional geometries work better, because the flexibility of the steel works better with longer tubes.

For any given tube - the longer the tube the greater the flex. It could be that the traditional geometries still sell simply becasue they are what people traditionally want - cyclists are a conservative bunch. All of the steel frames bikes that I have used for touring have flexed to some degree - one of them alarmingly so. Selecting a tube set using steel alloys with superior machanical properties will reduce the flex in any given design of frame.

What I don't understand is steel compact frames, like on the higher end Dawes Galaxies. Surely this compromises the ride quality of the steel in these bikes?

One marketing ploy that I've encountered is the promotion of compact geometries transmit more power to the rear wheel because less work is expended on flexing the frame. In terms of ride quality, you need to remember that touring bikes use wider tyres which probably offer more in enhancing ride comfort than using steel rather than aluminium for any given geometry. A stiffer frame in this context could mean more miles for your effort. Being conservative and tight fisted I'd still buy the base model Galaxy in preference to then other two models.

 

[Chris James]

what's incorrect in your posting is that you're trying to make out aluminium will ALWAYS eventually fail due to flexing, but since aluminium bikes have tubes that are fat enough not to exhibit any significant flex, they never really suffer any fatigue BECAUSE of the fact that they DON'T flex. Fatigue can only occur with movement and repeated compression and stretching, over and over again. Like bending a paper clip till it breaks.
IF an aluminium bike was made out of thinner tubes, then it would flex and would fail, in a way that steel might not - but you're trying to equate a 'what if' with realilty. Aluminium might be weaker than steel for the same dimensions, but it's NOT generally made into bikes using the same dimensions as steel bikes.

Bonj. I actually covered this in one of my earlier posts, but here goes again. Aluminium alloy frames do flex. But they are made with thick walls and large diameters to LIMIT the amount of flex (and thereby fatigue stresses generated) - so as to prevent EARLY failure.

Therefore, despite the FACT that aluminium will ALWAYS fail at some point due to fatigue, the frames can be designed such that it takes an incredibly long time to reach that point. The side effect fo this is that the frame is incredibly stiff (uncomfortably so?).

 

[Abitrary]

In terms of ride quality, you need to remember that touring bikes use wider tyres which probably offer more in enhancing ride comfort than using steel rather than aluminium for any given geometry.

This is my my main point with the perceived comfort aspect of a steel frame on a touring bike. The wider tyres will probably contribute a greater deal than the actual frame material.

I see steel as being more useful for a fast touring / audax type bike which will have smaller tyres.

 

[Bonj Hovi]

I see steel as being more useful for a fast touring / audax type bike which will have smaller tyres.

Why?

 

[bonj2]

Oh Bonj,

As ever the idiot (sans savant).

Aluminium framed bikes have to have fat tubes to overcome the the inherent weakness of the mechanical properties of aluminium i.e. it work hardens then fails if it flexes. They don't readily fall apart because they have to be designed not to flex to overcome the propensity of aluminium to fail after a finite number of stress cycles.

exactly, IF it flexes. But it DOESN'T flex. Therefore it DOESN'T break.

Is your bike made out of aluminium, Bonj? Pure aluminium?

bits of it are probably steel, but the frame is aluminium - i don't know about pure aluminium, possibly aluminium alloy, but mainly aluminium. Why, are you trying to trick me? Were you genuinely curious, or do you already know the answer, and are now going to tell me I'm wrong?

Bonj. I actually covered this in one of my earlier posts, but here goes again. Aluminium alloy frames do flex. But they are made with thick walls and large diameters to LIMIT the amount of flex (and thereby fatigue stresses generated) - so as to prevent EARLY failure.

The point is that while it may flex on a microscopic scale, it doesn't flex significantly.

Therefore, despite the FACT that aluminium will ALWAYS fail at some point due to fatigue, the frames can be designed such that it takes an incredibly long time to reach that point. The side effect fo this is that the frame is incredibly stiff (uncomfortably so?).

It will always fail, given infinite time, yes. You appear to have extrapolated the notion that because of (a) only a limited amount of flexing can occur before it breaks, and ( some flexing always does occur, no matter how significant, then a frame will therefore ALWAYS break. But you're attempting to equate molecular physics processes with general use and wear and tear of a bicycle. The two don't mix. It could be that it takes thousands of years of hard riding for it to reach the point of breaking. You appear to be then using this as leverage of your argument that steel frames are therefore better.
But hang on a sec - roll back a bit. If the advantage of steel frames is that they don't break, then how come there's stories of blokes in the tour de france in 1913 and 1919 etc having to stop at farms and blacksmiths and borrow a welder to weld their frame and forks back together, after they'd broke? And don't try and tell me they had aluminium in those days 'cos they didn't.


And, furthermore, if you're such an expert on materials science, explain this to me on a physical level: how, after a year of riding, are the molecules in an aluminium frame arranged any differently to when new, in such a way that makes the frame more likely to break?

 

[Bonj Hovi]

And, furthermore, if you're such an expert on materials science, explain this to me on a physical level: how, after a year of riding, are the molecules in an aluminium frame arranged any differently to when new, in such a way that makes the frame more likely to break?

Bonj, oh Bonj, oh Bonj,

Your ramblings offer further support to you being positioned on the autistic spectrum.

You can not embrace any ideas outside your limited notion of reality.

You challenge anything that contradicts your empirical grasp of reality without you being able to offer any tangible proof of your understanding of the underlying science that demonstrates that you are laughable wrong.

You are a very entertaining idiot who provides endless mirth for all who read your egocentric drivel.

Keep it up.