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HAMMER MAN
04-24-06, 06:21 AM
I plan on replacing my stem and drop bar on my Trek 5.5., the bars are carbon and the stem is aluminum.
I had a crash 4 months ago and @ the time the bars seemed ok.
Recently while cleaning everything I noticed some fine type dust/crystals in side the bars, so i figured best to replace them
They are the older model Easton carbon Ec90 25mm.
stem is a Richie WCS aluminum

Now out of curiosity would there be a big difference between all aluminnnum stems and drop bars or all carbon stem and drop bars with ride quality, vibrations,road buzz, possible fatique factor concernings the difference in material and the fact of a full carbon frame.
grams and price is not that big of a factor for me.

Blackberry
04-24-06, 07:36 AM
Don't have an answer for you HammerMan, but I do think you're wise to be replacing your stem. I was watching the Paris Roubaix race on OLN a couple of weeks ago, and George Hincapie, who had been in a crash earlier in the day, had his steerer tube snap in two. He was in contention for victory at the time. He wound up in the hospital after flying ass-over-teacups onto the side of the road. It was
speculated that the earlier crash weakened his steerer in ways that weren't visible at the time.

BTW, it just occurs to me that you might want to try a vibration-reducing handlbar tape along the lines of the following. I have no personal experience with it, but it might help:

http://www.specialized.com/bc/SBCEqProduct.jsp?spid=10018

GrannyGear
04-24-06, 07:55 AM
No experience with carbon, but if you have doubt, I wonder if the burden of deep background anxiety on a fast downhill sweeper outweighs the perhaps marginally perceptive weight/damping gains between carbon and more traditional alloy. Peace of mind in your machine helps you go faster! ;)

NOS88
04-24-06, 09:03 AM
I've ridden my current bike (Full carbon frame, fork and seat post) with carbon bars (Performance house brand bars) and aluminum bars (Ritchey Pro). I found very little difference in terms or vibration/road buzz. IMHO the gloves I'm wearing make more of a difference. I went back to aluminum bars with a Ritchey Pro stem, because there was a creaking sound with the carbon bars and aluminum stem I couldn't get rid of.

jazzy_cyclist
04-24-06, 10:06 AM
The frame I'm building up now (Look 555) has the FSA K-Wing carbon bars, and so far it has an alloy stem, so I hope it's okay.

John E
04-24-06, 12:54 PM
Yes, I am admittedly extremely old school, but there is no way I would entrust my life to carbon forks or stems. The San Diego bicycling community recently lost a valued member when his carbon fork snapped. My lightest bike weighs a whopping 10kg; so what?

HAMMER MAN
04-24-06, 01:07 PM
failure can happen in any products depending on fatique factors, torque and alot of that has probably not been explored fully with all variables of terrain, rider ability/strength and climatic factors.

just for the heck of it I went to Easton/Ritchie/deada to see the cost difference and for the weight weenies in grams
for 10 grams less you can pay as much as $200.00 dollars more for carbon stem/carbon drop bars.
quite interesting.

Ex: the difference between ritchie aluminum stem and drop bars verses all carbon the weight savings is a mere 5 grams.
cost savings is about $250.00.

GrannyGear
04-24-06, 01:09 PM
Except on occasion ;) , I don't generate the kind of power and equipment stress that Tom Boonen does. I agree that a good steel fork with the right gloves, tape, and riding habits, can be more than damping enough....as well as ride-and-forget-it. Likewise for stems and bars. We here more often want comfort rather than marginal weight/stiffness gains.... still, it would be fun to ride some carbon and see how meaningful those differences are. Like John E., my garage is full of steel.

jazzy_cyclist
04-24-06, 01:24 PM
My understanding is that it was not Hincapie's bars, but his steerer that gave way; not sure if it was carbon or alloy steerer.

One of the reasons that I'm building up a mostly CF bike is to try it out, as well as a host of other things: compact cranks, different wheels, etc. As far as I'm concerned, CF is absolutely mainstream. But next time I ride Paris-Roubaix :eek: , I'll consider a different material.

HAMMER MAN
04-24-06, 01:32 PM
if all of discovery bikes are as they say they are,{same as John Q Public} bontrager equipment, the forks all have aluminum steerer tubes from their xxx triple lite to x lite and lite unless I missed something, it the news/article said it was the the fork not the drop bars.
Maybe I am wrong, don't know, does anyone really know?

stapfam
04-24-06, 03:05 PM
if all of discovery bikes are as they say they are,{same as John Q Public} bontrager equipment, the forks all have aluminum steerer tubes from their xxx triple lite to x lite and lite unless I missed something, it the news/article said it was the the fork not the drop bars.
Maybe I am wrong, don't know, does anyone really know?

I watched Hincapies accident on TV and his Steerer tube had broken, just as it came out of the head tube. I did not realise that he had already had an accident- but one of the problems with Lightweight racing equipment is that it is Just about strong enough. One hard knock and the steerer tube was probably damaged- Then put a damaged part under further stress, such as the cobbles he was riding over at the time- and there is a chance of failure. I believe that the steerer tube was aluminium. but you can bet that it was a lightweight version and would have been just about strong enough for normal riding- and not be able to take many knocks. Carbon fibre is stronger than aluminium and has certain properties that make it more suitable to certain conditions. It is lighter- stronger- flexes a bit more than other materials and does not deform. Downside is that it cannot take any impact at all. If it does not shatter on the impact- then it can be internally damaged and just a slight bit of strain going into it- and it will break. That initial damage may not be seen- but any crazing of outer coat or signs of delamination of the fibres- and that item has to be scrapped. In fact- as a lot of the time damage cannot be seen- if the part has taken any impact at all- then the part should be scrapped.
Now I have scared the lot of you off of Carbon fibre- There are certain manufacturing techniques that are utilised in non racing equipment that make it safer without adding a great deal of weight. Difficult to explain how it is done- but rest assured that it is done.

(One of the parts of my Motor racing was as a fibre glass Laminator when Carbon Fibre was just beginning to be used extensively)

When saying Lightweight racing equipment- What I should have said was Lightweight Factory Team Equipment- that No-one will be able to buy- as it will be ultra lightweight, Absolutely Flawless and will only go to riders in the factory team. Joe public will not be able to get his hands on any of this grade of parts, ansd according to the factory it does not exist.

GrannyGear
04-24-06, 03:09 PM
VeloNews reported the steerer tube, not the bars or the fork, snapped. Lay this on on alu not carbon. Though most of us may know of at least one local rider whose carbon parts have failed. In all fairness, there are riders local to me who have logged lotsa miles on carbon with no problems.

Mr. Fierte
04-24-06, 04:50 PM
Not only did Hincapie's fork use and aluminum steerer but, it was a production fork. In this clip it claims to be from Trek's Satellite series (whatever that is) but, in another article I read the Trek rep said it was from the Pilot series of bikes.

http://www.cyclingnews.com/photos/2006/apr06/roubaix06/index.php?id=hincapie_trek/IMG_9943

jppe
04-24-06, 05:24 PM
It's just my personal preference, but I'm more comfortable having an aluminum steerer tube and bars. There's hardly any weight difference and with a carbon fork the road vibrations should not be too pronounced. I can deal with it anyway.

I just feel a little safer with that setup. That little peace of mind helps me quite a bit when hurdling down descents at 40+ and 50+........as long at my tires, tubes hold up!!

cyclintom
04-24-06, 05:39 PM
Big Paulie shows a picture of a Trek and implies in the text that this was a fork or stem failure. Looking at it myself it appears that the stem wasn't properly tightened on the steering tube and simply came off.

I've seen several pictures like this and in every case it looks like an assembly error and not a failure.

Theoretically carbon should be a more reliable than aluminum for handlebars and aluminum should be better for stems because of the joints in the stem. But aluminum has been used for handlebars a long time and the bugs are worked out of that process. We aren't as educated about carbon bars at this time though I'm crazy enough to have a set of carbon bars on my all carbon C40.

What we can be sure of is that people will continue to demand stupid light components. At this time it appears to me that lightening up a good standard bike such as a 20 lb Trek aluminum bike will cost you something like $1000 lb until you get to 18 lbs and then $200 and ounce after that.

My bikes weight between 21 lbs ($7000 C40), 22 lbs (Eddy Merckx Ex Pro), 23.34 lbs (Look KG241) and 24.5 lbs ($1100 Basso Loto) WITH SEAT PACK, WATER BOTTLE FULL, PUMP and air in the tires.

Looking at numbers like that makes you want to buy a Fuji Newest (mine weighs 23.45 lbs).

cyclintom
04-24-06, 05:42 PM
Not only did Hincapie's fork use and aluminum steerer but, it was a production fork. In this clip it claims to be from Trek's Satellite series (whatever that is) but, in another article I read the Trek rep said it was from the Pilot series of bikes.

http://www.cyclingnews.com/photos/2006/apr06/roubaix06/index.php?id=hincapie_trek/IMG_9943
You have to be careful of what you see in stupid articles like that. There's no way of telling what they did to that fork to try to get it ready for Paris-Roubaix. My GUESS is that they machined the steering tube thinner to lighten the fork some.

I'm NOT a fan of aluminum steerers but there's no good reason to fear modern materials.

NOS88
04-24-06, 05:55 PM
I remember when C'Dale first started production of aluminum bikes. There was consistent talk and buzz about the fatigue factor of aluminum, and how it would never hold up to good steel. I think history has shown that aluminum has done fairly well. I also know of several riders who've had their steel forks fold under the right conditions. If I remember there was a British bike (Lambert?) that was quite lite for it's time (maybe the 70s or 80s), and there were several riders who had chain stay, down tube, and/or head tube failure. I suspect almost anyting will fail under the right conditions.

zonatandem
04-24-06, 05:55 PM
Over 10,000 miles on custom ariZona carbon fiber tandem with c/f fork/steerer, bars, alu pilot stem and c/f adjustable stoker stem. No failures so far.
Have broken 2 steel frames and steel experimental fork. So will everybody quit riding steel now?

John E
04-24-06, 08:04 PM
I agree with Big Paulie. State-of-the-art racing equipment has reached the point that it is no longer safe or cost-effective for John Q. Public. This is quite a contrast from 30 years ago, when a club rider could buy a Peugeot PX-10 or a Bianchi Specialissima off the rack, possibly change to wider-ratio gears and clinchers, and happily go out riding on a safe, practical, fun machine. This is one reason I am so passionate about classic road bikes; they made sense when they were manufactured, and they are not obsolete in any way.

GrannyGear
04-24-06, 08:24 PM
This is one reason I am so passionate about classic road bikes; they made sense when they were manufactured, and they are not obsolete in any way.

Without being retro, and wishing to avoid being elitist, and certainly not OCP.........recreational cyclists can understand that the evolution of racing equipment does not parallel or move at the same pace as that of (even serious) recreational needs. Except that perceived needs, either inherent or manufactured by cycling marketers, makes it so. An old rant.

Seeing as how I don't have a tractor trailer full of whole bikes and spare parts following me, nor do I regard $40 chains as throwaway items, and I like relative peace of mind on fast downhill turns....I'll opt for a an extra few pounds (better that I shed a few of my own pounds instead of the bike) and a "bike for all seasons". I agree with John E. not for sentimental or "ye olde italianisme" reasons-- but for hardcore practical reasons.

:eek: I recall when most hot local riders bought their bikes from a local custom maker who ran a lawnmower repair in the front of his shop. They raced Cat 2 and even 1 and did just fine. Though no longer cutting edge for racing, those bikes still ride beautifully and, to make a point, they still ride.