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bicyclerider
Sunday, 8 March 2015
Drillium - its back!
Topic: Bike gear

Back in the day.... probably a few years before I was being born -- a strange craze swept cycling.  People were taking perfectly good arts and drilling holes in them. 

The idea was to save some weight -- but also create a pleasing design in the process.  Some guys did professional quality work, but many more were the shop employees or racers or just plain garage mechanics who tinkered.

Some drillium made enough of an impact that mass-produced parts started being sold with the holes already in them (of course, even back then, liability was an apparent concern; I've read that the holy parts weighed more than the unholed ones, indicating they were probably beefed up first, which sort of defeated the "hole"  purpose.  Be that as it may, however, note that the Campagnolo Nuovo Record brake levers were undrilled from the factory.  Super Record, which came later, had factory-drilled levers.

In short, drillium was big enough to influence the industry.  Even today, the popularity of drilled parts among "retro" riders enables companies like Velo Orange to offer "drillium" chainrings and cranks.  Of course, this is a niche market.  The truth is, Drillium hasn't been big for years.  Why?  One might as well ponder the nature of gravity.  Some say excessively drilled parts broke; others that as Super Record supplanted Nuovo Record there was less market for drilling; and of course, then parts started being made of carbon and stuff and this trend passed into history.

Sort of.

The truth is, there is always someone out there who tinkers.  I did this back in the 1990s to the shift levers on my old Gitane, because they were old enough to be "period" and i wanted to see how to do it, but except for the odd chainring, or sometimes chainrings made into home-made bash guards fro mountain bike use, those Suntour shift levers were all I ever drilled out before.  So after stumbling on some pics onlien that remonded me of my long-deceased Gitane, I decided to follow in the footsteps of the 70's, and drilled out a pair of dia-compe brakes.  Not bad, so I did the 105 group on my Trek 470... front and rear derailliuers, downtube shifters, brakes, and lastly, the brake levers.  My friend who runs a bike shop told me brake levers are hard to do and in the olden days guys built special jigs.  I did it freehand with a cordless drill while listening to oldies radio.

Now... if only I had more parts to practice on...!


Posted by blog/bicyclerider at 5:06 PM EST
Updated: Sunday, 8 March 2015 5:15 PM EST
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Monday, 7 April 2014
Press fit bottom brackets: A solution in search of a problem?
Topic: Bike gear

(To get on a soapbox for a second, however) Regarding new technology and the impression it doesn't have trade-off's: it does.

If fact, the BB30 might be a prime example. Invented according to lore by Cannondale, it is now used on many other bikes and been observed on many high end, high dollar frames -- Cervelo, the aforementioned Cannondale, etc.

Since these bearings are "press fit" they have to be removed with a mallet. WTF? Really? On a ,000 bike?
Second, being press fit, the bearing tension is adjustable only by the bb shell width of the frame itself. In other words, a slight tolerance issue in frame sizing and the bb will be either lose or tight, no way to adjust it (although one might sand or file down the edge of the frame?)
Similarly a BB30's advantage, according to one Cannondale spiel, was it's stiffness. However, A press fit bottom bracket with improved stiffness is just that. What'd that Ancient Greek guy say? Give me a lever and a place to stand... and I'll move the world? The crank is the lever and the BB is literally, where it stands. Is anchored. Here's the problem; Imagine a massive strong lever. It is more effective at transmitting energy. Good, right? Yeh. But it doesn't help if at some point a long the way all the energy is wasted. Say, you have this awesome lever -- but are standing on a soft yielding surface. Or something slippery. Maybe you're wearing roller skates. Okay, the lever won't flex a micron -- but you will lose energy because you, who are holding the lever, slip.
A press fit bottom bracket is like that. The newer, stiffer bb may be more efficient at transmitting energy, with less flex, and the lighter bb may mean that less of that energy is wasted on moving a heavy bike part down the road, or in a circle... but if the attachment point is a source of wasted energy, all that stiffer newer bb means is more squeaky bottom brackets where the press fit parts hits the frame's bottom bracket shell. Squeaking, for those who don't know, is the sound of movement. That movement means the loss of energy.
Indeed, you have a new stiffer spindle and stiffer bottom bracket -- that's press fit into a frame with a new stiffer bottom bracket shell and frame area.

See the problem? The bb to bb shell/frame interface is press fit -- the weakest link in the chain running from your feet, through that newer stiffer bb, to the rear wheel.

Not to put too fine a point on it, but all that stiffer bb will do is creak more. And with only a press fit attachment point it's not like there are threads that can be greased. in short you have to remember the bike is the sum of it's parts, at least in one respect. The bb is only as strong as its attachment to the frame. Now if you are okay with a k bike - or any bike - that squeaks, so be it, but I wouldn't be.

Make no mistake, the BB30 has advantages, but let's just not forget that like everything else it has a trade-off too. Cyclists -- like anyone else -- engage in such trade-offs all the time. For instance, A carbon frame is light, but not very great at surviving impacts unscathed. So you make a call -- which is more important, short term performance vs. long term durability? For racers this is a no-brainer. For the rest of us, it is a real question, because most of us "real world" riders have to buy our own equipment and don't get new stuff every year. Also our bikes have slightly less specialized roles than racer's bikes. For the regular rider, his bike isn't just a piece sporting equipment, it's also a vehicle, a way to get to the store, etc. And while granted, a person is probably not going to commute on a pure race machine, they could. This is where one of the other great misfortunes of modern cycling technology comes into play, the horrible lack of tire clearance on many bikes. Sure racers aren't running 25s or 28s, but then racers don't have to ride after work in the dark or early Saturday mornings over post-winter roads. Have you seen the potholes out there?
True there is a place for specialized racing machines -- see the classic racing aesthetics of a lugged steel frame, chrome, and Campy N. Record! But... even though you want to be able to ride as a racer, you shoot yourself in the foot if you totally lose all ability to use the bike for anything else except keeping up with the guy in front of you. The fact that if you are really an avid cyclist, you probably have a less "racy" bike to commute on, doesn't change this observation.

As to the trade offs; they aren't new. Old Vitus frames were light, but reportedly flexed a great deal. Aero or v-section rims are more aerodynamic, allegedly -- but heavier rotational weight (more material. To try and minimize this trade-off they use carbon for many of the high-end aero rims; it's light but more delicate; another trade off. An aero rims also need special long valve stems.

Not all trade-offs are worthwhile -- or commercially viable. The Lampert and Viscounts both claimed to use airplane related materials and technologies -- and became obsolete curiosities, mainly due to the fear that their fork blades would come off. Not all new technology is successful. It is ironic, then, to note that the Lampert had a press-fit bottom bracket, like the BB30. And while Viscounts and Lamperts are in my humble opinion really awesome vintage bikes, as well as sort of iconic historical things, you wouldn't probably want to put 5,000 miles a year on one. At least I wouldn't. So while the modern cyclist, who "knows better," may smile knowingly at the somewhat quaint images of the decades old Lampert ads touting "aerospace technology!", are we any more sophisticated when we run out and buy a BB30 -- just because it's "newer and stiffer and lighter"?

The modern press fit bb, the BB30 included, has the same practical trade-off as any other technology. For example, a BB30 *is* lighter and stiffer, or *should* be if made properly; a press-fit design needs less material in terms of thickness than a design with threads in it, as the threads consume part of the initial thickness. This is true on both the frame and removable bottom bracket. And a wider spindle is stiffer. The downsides are a squeaky bb-bb shell/frame junction, and no real adjustability to bearing tension.

 Oh, and having to whack your expensive lightweight fragile frame to get it out using a mallet.

BB30's may actually feel nice while riding.  They definately have potential weight savings.  But... gee, how much is that Cervelo worth?  Three grand?  And you're gonna hit it with a hammer?

Of course with modern cartridge or self-contained bearings adjustability is less of an issue anyway, and has been less of an issue, for years, since before outboard bearings, back when we all used square taper bb's and nothing else. Once bb's went to cartridge or self-contained bearings, that was a big change, bigger perhaps than bearing size or location. Because the purpose of the bearings changed. Now they were more replaceable parts than an integral component of the bottom bracket itself. You didn't adjust the bearings as they loosen; you threw em away and replaced 'em. It is a different attitude.

 Without it we'd never have seen BB30's.

Maybe it's the attitude of the future. We'll see. )

 

Personally I think they should bring back 3-piece bottom brackets, with the bearing cups and square taper separate spindle.  These were lighter than sealer bearing ones, though probably not as lighrt as BB 30's and the ilk -- although they contain adjustibility the lighter more modern design doesn't -- and none of it's flaws.  They sure don't creak.

Dust off that thirty year old catologue.  What used to be old might be the next New Thing!

  Hey it worked for press fit bottom brackets (or, more to the point, it didn't, and doesn't).


Posted by blog/bicyclerider at 5:25 PM EDT
Updated: Monday, 7 April 2014 5:31 PM EDT
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Testing the moustache bars
Topic: Bike gear

 

And now -- for something Completely Different!  Moustache bars -- offroad? 

What kind of wierdness is that?

Well, having put a pair of moustache bars on an old road bike, I recently tried them on my Surly 1x1.  I have to say I'm thrilled with the results.

Indeed, my initial impressions of the bars are that they are probably better suited for use on a mountain bike or even a dual duty street/dirt "all rounder", than a roadbike -- although they work well on the roadbike, too.  Or, perhaps, it is not so much that they aren't good on the road bike as simpyl just better on the 1x1. 

This should be no surprise.  Grant Petersen designed the first "moustache bar" for the XO-1, a cross between a mountain and road bike that was indeed an "all rounder" or a bike suited for multiple surfaces.

First, the set up.  Like the roadbike, putting the moustache bars on a mountainbike involved a higher raised stem. 

This is because although the bars do not have much "drop", compared to traditional road bars, they aren't level, either.  The curved parts with the major hand positions are slightly lower than the central clamp area (See my page on moustache bars, https://www.angelfire.com/blog/bicyclerider/Moustachebars.html ...more on this).  Oddly enough, a friend recently asked me if the original XO-1 moustache bar had the short but noticable drop.  I seem to remember some that were level, just curved, but can't be sure.  Maybe the nittos.  Mine are more inexpensive Origin8 Tiki bars and like most variants between different companies I am sure the shape is not entirely the same. Each maker or brand -- Soma, Nitto, Origin8, etc -- has all given us their own interpretation of the moustache bar.

I used a stem with a short reach, sharp long rise (110mm in length, but more than 4" in height) like I did on the Lemond roadbike.  Oddly enough while it seemed after a while like it could've been just a hair too far forward on the Lemond  it seemed just fine on the Surly -- in fact a shorter stem might've led to the ends of the bars risking a knee strike in a low speed turn.  I put this down to the 1x1's short top tube.

The ride:  On the road you cruise with your hands in the curves, by the brake levers, but sometimes at speed there is a tendency to move them back to the flat straight ends.  Aslo, then standing on the pedals, you move your hands to the flat sections.  I experimented with repositioning the brake hoods slightly and yeh you can use those -- but it's not great.

Offroad tests included a short dirt jaunt followed by gravel -- rocks, really.  With the recent rains I didn't feel like tearing things up but it worked out okay and I have to say riding over a dirt path paved with fist sized peices of gravel gave me an idea of what those old-timey bike races must have faced dealing with cobbled roads.  Ouch.

Nevertheless, the rocks -- which had been put down on a trail through the woods so that power-line repair crews could get back there this past year -- were a great test of the bars as far as offroad handling was concerned.

What I learned was that over road surfaces, you have great control.  It would seem the other way around, mountain-bike type flat or riser bars would seem to be better, and for some things they might be -- I am not sure yet how I woudl lift up the front wheel the way I would with a flat or riser. 

However, for control in riding (if not jumping) terrain or obstacles you can't beat it.  This is true even if the bike itself -- being singlespeed -- was probably overgeared for offroad use (I had it at 42x18 , a 42 tooth front ring and a double sides rear wheel with an 16 cog on one side and an 18 on the other... I've since dropped it down to 34x16, but that seems too low.  Maybe a 36 or 39t chainring will be in it's future.  I have to find a gear that works offroad but still cruises on the street.  Right now the 34x16 is okay for around town but to get up tp 20mph I have to spin like mighty mouse and it is not enjoyable.  Or I may leave it... we'll see)

The moustache bar does indeed work offroad.  For those who want to try something completely different, give it a try.

 


Posted by blog/bicyclerider at 10:38 AM EDT
Updated: Monday, 7 April 2014 5:34 PM EDT
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