Are Steel stems, bars, seat posts safer? Discuss...

[ultrazenith]

Aluminium bars, stems and seatpost only really snap if overloaded in a crash or simalr. Carbon part normaly fail if clamps to tight or crashed. None of which can be blamed on the part. Steel bars, stems and post are simply heavy well maybe not the post so much but weigh your bike down unnecessilarly.

I think there are two main ways for metal to fail: - repeated flexing under normal riding conditions, leading to eventual fatigue (gradual cracking and then catastrophic failure), and instant snapping/bending due to massively overloading the part (i.e., in a crash).

I've never found steel to be that much heavier than aluminium, unless you're a weight weenie who would covet a saving of ~100 g off a handlebar or seatpost.

 

[bm0p700f]

Well 100g on the post and bars is 200g. Then add all the other not so light kit and you have a 1kg or 2. While I am not a weight weenies I do prefer my road bike to be under 10kg.

Again when was the last time you saw a ally bar snap from fatigue. I know it can happen but it not exactly common. Shops are not recieving these every day you know. It not like broken spokes.

 

[Neil]

Well 100g on the post and bars is 200g. Then add all the other not so light kit and you have a 1kg or 2.

Baby / bathwater.

Just because you don't save weight in some areas that perhaps are more catastrophic if they fail - doesn't have to mean you don't opt for lighter kit as and where makes sense.

In reality, 200g heavier bike because people have made more sturdy choices in some areas, is a drop in the fecking ocean. My morning dump probably weighs more, as does any number of things you might take with you on a ride.

And how many people could stand to lose a pound or two? Slightly beefier components in certain places, doesn't necessarily make for a heftier bike, and transform something from being sprightly to dead weight. That only happens when people are a good stone or more overweight, and still obsessing that they've suddenly made their bike nice, light and responsive because their stem, bars and seatpost are lighter by 100g.

 

[ultrazenith]

Well 100g on the post and bars is 200g. Then add all the other not so light kit and you have a 1kg or 2. While I am not a weight weenies I do prefer my road bike to be under 10kg.

I see your point. When it comes to steel, I target only those components whose integrity while riding is a life and death situation, and I can live with an extra 300 g on my bike.

Again when was the last time you saw a ally bar snap from fatigue. I know it can happen but it not exactly common. Shops are not recieving these every day you know. It not like broken spokes.

I've killed an alu bar through fatigue, during a mere 1 year of usage. My brother had 2 cases of his bar snapping while riding, luckily not resulting in a serious crash, again both cases were fatigue (he didn't realise what the clicking of the bar meant...).

I'd guess an ordinary/cheap alu bar might take around 1-2 years of hard riding to fail through fatigue, so no, you won't be seeing people in every day with a snapped bar.

 

[Raging_Bulls]

Re: Re:

Let's kick off a "let's see your failed steel " thread. Bend mech hangers not counted

Shouldn't have said that, maybe I will ...

Not mine actually, but I had one with the exact same problem.

 

[mattr]

Steel has a practically limitless fatigue life, although any material will fail if overstressed. There are enough pre-war steel frames around as evidence. I would avoid anything ultra light.

Except that ti has between 50 and 150% better fatigue properties than steel.
Depending on which grades you compare.........

 

[EggyBum6969]

newbie bikers could be made paranoid by some of the comments about alu,

i know there were some faulty turbine stem plates
which were recalled an replaced with thicker ones

an Ive heard of a few old turbine cranks cracking

but Ive never heard of a set of raceface bars snapping
Ive got 15year old ones here an a fair few others up to current
dues an never had a creak crack or bend in them
Ive put some through a lot of grief an they don't vibe an flex
like a set of amoeba scud bars

the 2006 marin bars i got off cheesie on here are so thick stiff tough
an rather heavy for 6061 i think they could survive a nuke

don't over tighten the stem bolts

I'm sure that threre is a lot of mtb commuters with years of miles
on there bars too

an as for people that only get out
for a few hours on a Sunday I'm fairly sure they will be fine
on the resurfaced former railway tracks an cycle lanes
as long as the person who built there bike didn't over tighten stuff

 

[M-Power]

Re:

You should give your bike either a clean and check after every hard ride or just a check over. Examine around the stem/bar contact points, seat post clamps and the frame. It's normally possible to see evidence of stress risers, bending or cracks starting before they finally fail. If you take massive air, land badly or crash you already know what can happen.

Personally I never went for the absolute lightest components at the expense of safety or durability. Nothing wrong with a steel ATB weighing 24lbs. Loose a few lbs and just get fitter

 

[Mr.Toad]

Re:

Mr. Igleheart has great advice regarding care and inspection of bikes.

http://igleheartcustomframesandforks.com/care/

 

[FSXStumpy]

I've long ridden with 150g, 155 and 170g alu flat bars (Richeys, Zooms and others) on my bike, though most of my REAL riding was done BITD, from 1993 thru 1999 or so.

I failed about 4 or 6 bars in that time frame. 2 failed from genuine fatigue (not overstress, but failed while sustaining "normal" loads after about a year's use), each time cracking on the compression (bottom) side of the bar, and giving way, not abrupt failure, but a loss of rigidity and distortion of the bar. It did happen. Not from scoring or anything, but just high cyclic loads. The remainder were binned as a result of damage to the ends of the bar from barends during crashes.

That said, never did the breaking bar itself cause a crash, even the time it let go halfway down a staircase... Was a touch exciting for a few seconds, though.

Racing equipment has always been a fine line between durable enough and light enough. Lighter always carries risks. Check'em regularly, any bulge that wasn't there before is a sign.

J