Dura Ace - Ultegra

[nellie]

 

Dylan' date=' Titanium is lighter than steel, but not stronger. It is stronger than aluminium though, but not twice as strong.

Titanium has about half the density (thus weight) of steel and double the density of aluminium.

 

Compared to steel, titanium is a very poor wear material in applications such as sprockets. It is much softer than steel.

 

Further, titanium is extremely difficult to machine, weld and heat treat. Therefore you'll see lots of reports of cracks in titanium frames. Absolute strength isn't always the whole story. It may be stronger than aluminium, but makes a poorer frame.

 

If you look at titanium's weaknesses, you'll see why it is only used on the top three sprockets of bicycled clusters. Those are the sprockets that racers are prohibited by peer pressure, never to ride in.

 

Titanium is also very expensive, mostly because of the high energy needed to extract it from its mineral form, titanium oxide.

 

[/quote']

 

oooh...i see a fight coming on...

 

just checking the members list and most of the dangerous characters are not on, but there's quite a few people that swear by Titanium...

 

I'm clueless and indifferent....interesting reading though - didn't know that.

[Johan Bornman]

I was not aware of that. I have been mislead into believing that titanium is lighter and stronger than steel? Are Ultegra sprockets made from Alu' date=' steel or alloy?

Thanks Johan, I always appreciate your insight.
[/quote']

 

Sorry Dylan, I see I didn't really answer your question but went of on a tangent about titanium instead.

 

Ultegra sprockets are, as far as I know, all made of steel. Most sprockets are made of steel except the top few on top end model.

 

However, you also ask about Alu, steel or alloy.

 

There's quite a bit of confusion in the bicycle market about the word "alloy." An alloy is a mixture of two or more metals. There are therefore an infinite number of alloys possible.

 

 

 For instance, Steel is an alloy made of iron and things like vanadium, molebdenum, chrome (as in stainless steel) . If it has iron, chrome and molebdenum in, it is referred to as Cromoly - a common steel for bicycles and spaceframes for cars, motorbikes and the like.

 

If iron is mixed, or alloyed with chrome, it becomes stainless steel, and so on.

 

Generally, even though the metal is a mixture, we refer to the majority metal. For instance, an aluminium alloy is simply called Aluminium. A steel alloy is simply called steel. But, there is always an exception to the rule. Some alloys have special names. A mixture of copper and zinc is called brass, even though it is predominantly copper. Likewise, a mixture of copper and tin is called bronze. Tin and lead is called pewter. These are the only three exceptions that come to mind now.

 

Very seldom are metals used in their purest form - it is extremely hard to purify it to the 100% state and most of the metals in our daily lives are thus alloyed.

 

So, to reach a conclusion to this essay, when cyclists refer to something as being made of alloy, they're slightly confused, since they think it is aluminium. If I wanted to be naughty, when customers ask for alloy nipples, I could technically give them brass and still not  be dishonest. Brass is an alloy.

 

 

 

 

 

[dylankeyter]

Thank you for clearing that up Johan. I though Aluminium was a pure state in its own, as on the periodic table, but you have confirmed my beliefs were wrong.

 

 

[Johan Bornman]

Thank you for clearing that up Johan. I though Aluminium was a pure state in its own' date=' as on the periodic table, but you have confirmed my beliefs were wrong.


[/quote']

 

No,  think I put you on the wrong track. Aluminium is a pure metal as found on the periodic table. But we don't call something that is make from aluminium alloy "alloy", we simply say "aluminium and assume that we actually mean "aluminium alloy. It's a bit of a nomenclature thing.

 

I'm confusing you, but I think if you read carefully through what I originally wrote it'll make sense.

 

 

[SwissVan]

Originally posted by Johan Bornman  "If you look at titanium's weaknesses' date=' you'll see why it is only used on the top three sprockets of bicycled clusters. Those are the sprockets that racers are prohibited by peer pressure, never to ride in."

.. bwhaa haa.. i think its more a case of less force and a smoother stroke being exerted on those sprockets , due to mainly used for climbing.. but thats just my opinion
[/quote']

 

Nope mi thinks your both wrongish...

 

The top 3 Ti sprockets are the largest (heaviest) sprockets and thus in theory it makes sense to save weight on them, making the smaller sprockets out of Ti would not make much diffs if you had to compare weight.

 

N? ?

 

 

[Johan Bornman]

Originally posted by Johan Bornman  "If you look at titanium's weaknesses' date=' you'll see why it is only used on the top three sprockets of bicycled clusters. Those are the sprockets that racers are prohibited by peer pressure, never to ride in."

.. bwhaa haa.. i think its more a case of less force and a smoother stroke being exerted on those sprockets , due to mainly used for climbing.. but thats just my opinion
[/quote']

 

Nope mi thinks your both wrongish...

 

The top 3 Ti sprockets are the largest (heaviest) sprockets and thus in theory it makes sense to save weight on them, making the smaller sprockets out of Ti would not make much diffs if you had to compare weight.

 

N? ?

 

 

 

Sorry, but you've both been had. My initial comment about peer pressure was pure tongue-in-cheek.

The reasons for attempting to get away with titanium large sprockets are obvious - weight. We live in a world where cyclists walk around with little scales in their pockets. I believe drug dealers do the same.

 

[SwissVan]

Originally posted by Johan Bornman  "If you look at titanium's weaknesses' date=' you'll see why it is only used on the top three sprockets of bicycled clusters. Those are the sprockets that racers are prohibited by peer pressure, never to ride in."

.. bwhaa haa.. i think its more a case of less force and a smoother stroke being exerted on those sprockets , due to mainly used for climbing.. but thats just my opinion
[/quote']

 

Nope mi thinks your both wrongish...

 

The top 3 Ti sprockets are the largest (heaviest) sprockets and thus in theory it makes sense to save weight on them, making the smaller sprockets out of Ti would not make much diffs if you had to compare weight.

 

N? ?

 

 

 

Sorry, but you've both been had. My initial comment about peer pressure was pure tongue-in-cheek.

The reasons for attempting to get away with titanium large sprockets are obvious - weight. We live in a world where cyclists walk around with little scales in their pockets. I believe drug dealers do the same.

 

 

 

Well thats a relief, for a minute a thought that the brains trust of the hub (no offence meant) had lost its marbles.

 

Yeah weight weenies, suprised they dont weight the amount of chain lube they use ...Luckily i dont stress 2much about my bike and parts weight ...

 

Anyways time for some  cappuccino and rusks...

Anyone know how many calories in 1 amarula cuppuccino with 1 health rusk ???