kraftwerk 

I was musing to a local bike shop mechanic about how I might alter the sweep and bend of a set of bars.
He said, horrified, "I would never ride on that bike! "

I was thinking...how does he know he is not talking to a metallurgical expert?
He wasn't..

...so I am asking here: if I properly anneal the bars first and use the correct-size pipe bender,
can I tweak the sweep of my bars? They are Velo Orange Tourist, just want to 'tuck' them back a bit.. so they don't 'wing-out' so much.
Maybe 1/4" each side? Any of you people have experience w/ this type of adjustment?

oldbobcat

I wouldn't if they were heat-treated. Otherwise, as long as you don't get too crazy, why not?

It's funny. A few of the guys I started racing with had Peugeot PX-10s and Gitane Tours de France, and after a couple years their stock bars that lacked reinforcement sleeves would sag from the stem. And sometimes they got bent in a crash, and we'd pull them straight again.

FBinNY 

As noted above heat treating is a critical consideration so the following assumes they're either not he treated at all or you properly anneal them first.

That said, certainly you can recurve the bars. That's how they were made in the first place. It's also how we saved crash damaged bars all the time, before everybody became paranoid about product liability lawsuits.

The key is to properly support the bar especially at the fulcrum of whatever you're using for leverage so you don't kink it, or produce a concentrated local bend. Since you're only talking about a slight change the curvature you should be fine as long as you're careful.

dsbrantjr

You can fill the bar with fine sand before bending them to help avoid it collapsing at the bend.

3alarmer 

...I am much less adventurous, and threw these away. They frightened me.

3alarmer 

.
...to the OP. I don't know definitely about your VO bar, but I suspect it is one of the modern alloy bars that are heat treated as a matter of course. It's how they make them lighter, out of thinner alloy tubing, and stronger nowadays. If all you are bending is the ends a little bit, you can probably get away with it. The major issue with an alloy bar breaking is when they break close to the stem, and you end up with one half of the bar waving around in the air, unable to steer, and with a very surprised look on your face.

At least, that's what I think I looked like, the one time i busted an old French handlebar. Very surprised...didn't have time to proceed to frightened.

Honestly, I would probably just shorten the ends with a tubing cutter, before I tried bending them. That should narrow them down a little.

Andrew R Stewart 

This question is one of those "if you have to ask than you don't know enough to do it" ones. I've watch a few handle bars crack and separate during riding, thankfully from the results I saw none were my own. But, hey, it's your bike and your risk value judgement. Just don't ride in any groups please. Andy

Trakhak

Someone posted a photo of a saggy bar here about 5 years ago and asked if the bar had come stock that way. A couple of people gave the (correct) explanation you just gave, but they were shouted down by the majority, who dismissed the possibility that the bending represented a design flaw and then discussed learnedly among themselves the advantages of a bar that was designed to sag next to the stem and to angle inward at the bottom.

mrv 

related to the topic, if you want more info..... and just plain fun. I bent a set of Noodle bars and opted to throw them away. I was nervous about bending them AND them being heat treated.


cheers.

BTinNYC

Then maybe 45 years later pulling the tape off vintage bars and there's weird perpendicular dings and stressy marks near the stem, "what's this?" 🤔

I tossed 'em this morning. At first I considered using them, 'the bike is more for show than go' and new tape will cover the dings...WTF am I thinking!

Into the recycle bin, next to the AVA stem that lost an epic battle for Who Controls the Fork.

oldbobcat

Boy, am I glad that I wasn't around for that one.

Makes me chuckle, though. I'd worked on a Specialized model, probably early versions of the Roubaix, that had an adjustable quill stem and an "anatomic" bar that drooped and swept back from the 25.4 mm center clamp. It was the ugliest looking most unusable bar I'd ever seen on a bike. Some crazy ideas went down in the name of Body Geometry.

oldbobcat

I looked it up. It isn't.

oldbobcat

The thing about soft aluminum is it will give you plenty of visual warning before it fails. But you gotta look under the tape. And 45 years is a half lifetime. Int the early '70s our bikes were all less than six years old.

About 10 or 15 years ago, a lot of guys were reporting that the spindles on their Lyotard 460D pedals were breaking, as if it were some major indictment of French metallurgy. Well, of course, Lyotard wasn't as good as Campagnolo, Shimano, or even MKS. But they'd gotten over 40 years of service from those pedals. What is the problem?

I got rid of the stock bar on my Raleigh International early on, just because I wanted something wider and stiffer for more confident sprinting. The first was a nifty GB bar. But in my club we all used Cinelli or 3T bars and stems eventually.

3alarmer 

...here is the VO page on this "Tourist" bar. Maybe I need a secret decoder ring, but I'm unable to find that information on the VO page. Is there some other link I'm missing ?

oldbobcat

A $42 tourist bar isn't going to be heat-treated. But just to be sure, I messaged VO. I'll let you know when I hear.

3alarmer 

...whether or not it's heat treated, why is it you insist on telling this guy that bending aluminum alloy ---any aluminum alloy---is a good idea ?
I honestly do not get it. If he wants only to narrow the span of these bars by a couple of inches, there's plenty of excess on the ends to remove with a plumbing cutter.

Quicker, probably easier, certainly less problematic in terms of adding additional stress to the stress risers that might already exist at the bends. Just because you can do something doesn't mean it's a good idea. If there's a way to accomplish the desired result that does not involve bending in the operation, why not avail yourself of it ? What am I missing here ?

79pmooney

I was given an old GB bar when I was just getting started. Went on my fix gear UO-8. Winter ride, second season of racing. I hit a bottomless pothole. Wheels made it so I rode on. 10 miles later I happened to look down. Bar was bent at the edge of the sleeve 30 degrees. (Fun story - that bike never left me stranded. That happened 20 miles from home but the discovery was 2 miles from my riding partner's house. I knew she had a train schedule on her kitchen door and that it wasn't locked so I rode over, saw a train in 45 minutes, rode 3/4 mile to the station and got off a mile from home. It was mid afternoon and not a commuter train so bikes were not allowed. Conductor started to tell me. I pointed to the handlebar. He said something to the effect that yes, I needed the ride and put the bike in baggage.)

And those platforms. I rode many pairs into the ground but never got them to last to spindle failure. That same fix gear. I'd loosen all the pressed joints in the pedal body. (And unscrew the left pedal caps with pedal scraped, UO-8s on sewups being VERY low bottom bracketed.) I still have a book of about 10 pounds of dead Leotards here somewhere but maybe one dustcap.

Fun memories. Thanks!

79pmooney

But closer to this thread - I don't even consider doing additional bends to modern aluminum bars. The old bars often fails like the GB of my last post, by bending, Hand still attached to the stem so rider probably still on the bike. All good. Modern, higher strength, thinner walled bars rarely bend, last longer but when they go, they break into two pieces. Those cables and housings are very poor substitutes for even 30 degree bent aluminum.

Plus I know all too well what can happen from a total failure between the front rubber on the road and my hands.


Edit: Instead I have had a bunch of stems custom made to put stock bars where I need them.

GamblerGORD53

You're asking about alu bars that can corrode in 2 years from sweat under wrap?? LOL.

easyupbug 

How to handle a possible outcome, about 55 seconds in: Still he finished third in this the 1989 Worlds with only the stem.

oldbobcat

The website for a company whose primary business is selling bikes that are at least 35 years old. https://steel-vintage.com/en/

They'd have been bankrupted from lawsuits long ago if all the handlebars assploded.

Mr. 66

Those bars were failing in the 70's, usually after being coldset from being drooping.

the Lyotard pedals also historically would break.

Another that would break is the pedal eye of Avocet triple cranks of the early to mid 80's cranks.

oldbobcat

First, It's not like he's changing the entire shap of the bar--he just wants to pull the ends in a fraction of an inch. The stress will be spread over an 18" length of tube. Second, it's a tourist bar. He's not going to be riding Paris-Roubaix cobbles with it. He's not going to be dropping off ledges on singletrack with it. He's not going sprint like Mark Cavendish with it. It steers the bike and serves as an attachment point for the brake and shift levers.

If it were my bike I wouldn't even bother, and I'm not encouraging him to do it. I've just seen handlebars made that way that kept working long after worse things happened to them.

KerryIrons

I think you said you were not a metallurgist, right? How then do you know how to "properly anneal" the bars? As I understand it, the annealing process depends very much on which alloy you have. But then I am not a metallurgist.

CliffordK

My guess is all the bars are heat treated. There was a youtube video about making handlebars. Quite a process of bending and expanding metal.

The thicker metal bars are likely 6061 or similar aluminum. The thinner bars would be 7000 series aluminum.

The OP seems to be aware of heat treating, and wants to first anneal the metal. If he can do that, perhaps he also has full heat treating capabilities.

Where do handlebars break? I'd assume that they are most susceptible to catastrophic failure within 2" of the stem. Bending the ends of the bars may not be a high stress area, assuming the bend is somewhere beyond the brake mount.