Showing posts with label extra-short wheelbase. Show all posts
Showing posts with label extra-short wheelbase. Show all posts

11 January 2017

Shorter And Shorter, A Century Apart

The other day, and in a few previous posts, I mentioned the Rigi frame.  It had twin vertical seat stays, like the twin laterals found on the "top tubes" of many classic mixte bikes (and Vera, my green Mercian mixte).  The rear wheel actually ran between those tubes.

The reason for it was to shorten the bike's chainstays and, therefore, wheelbase.  Shorter wheelbases make for quicker acceleration and response, all other things being equal.  Rigi was probably one of the more extreme results of a race, which ran its course during the late 1970s and early 1980s, to create bikes with the shortest possible wheelbases.

That trend resulted in other permutations of bike design, like curved seat tubes.  It seemed to run again, if briefly and less widespread, just before the turn of this century, when KHS and other companies made bikes (mainly track and fixed-gear) with curved seat tubes.

Like other fads, it's not new.  Within a few years of the invention of the "safety" bicycles, designers and builders had essentially figured out what we now know about bicycle geometry.  For the most part, bikes had longer wheelbases and shallower angles than the ones on current bikes because road conditions were worse (when, indeed, there were roads!). Also, few cyclists owned (or even had access) to more than one bike, so their steeds had to be more versatile.  And, I would imagine, the materials available then weren't as strong as what we have now (most bikes were still made of iron or mild steel) and could not withstand the pounding a shorter wheelbase and shallower angles--which absorb less shock than longer wheelbases and shallower angles--would deliver.

Still, there were apparent attempts to make bikes with shorter wheelbases at the turn from the 19th to the 20th Century. (I can still remember when "the turn of the century" meant the period from about 1890 until World War I!)  This one looks particularly interesting:




If you sneeze on this 1890s "Bronco" bike, you just might go backwards!  All right, I'm exaggerating, just a little.  What I find intriguing--almost astounding, really--is that the auction house selling the bike listed it as a "cross" bike.  Did they mean "cyclo-cross"?  If they did, I wonder whether the bike was intended as such when it was made--and, presumably ridden.

The auction house also says the bike has an "axle driven crank".  Today, we call that "fixed gear":  The wheel and pedals cannot turn independently of each other.  High-wheel or "penny farthing" bikes had such a system--on the front wheel.  

That is the reason why those bikes had such large front wheels:  To get what most of us, today, would consider to be a normal riding gear--let alone anything high enough to allow for any speed--a front wheel of at least 1.5 meters (60 inches) in diameter was necessary.

Hmm...That means the gear on the Bronco must be pretty low!

Low gear and short wheelbase:  Could this be a bike intended for uphill time trials?

29 June 2015

While His Fixie Gently Weeps



Sometimes I think that if Salvador Dali had composed music, it would’ve sounded something like the tune to  While My Guitar Gently Weeps”.

Now, if he’d designed bicycles it would have been interesting, to say the least. While going to the store, I think I saw an example of what might’ve resulted:



For one thing, I was intrigued that this bike came from Biria, a company that’s been known—at least in the US—mainly for city bikes with upright bars.  Perhaps if Biria’s focus is indeed urban bikes, this model makes sense.  After all, I don’t think very many people in small towns in Wyoming or West Virginia are going to ride a bike like that.



Another thing that caught my attention is how close the rear tire comes to the seat tube:



And that’s with the wheel all the way back in the dropout:



What’s even more interesting is that other attempts to shorten the wheelbase (or, at any rate, the rear part of it) have included curving the seat tube, as on this KHS bike from the mid-90’s:

 

And Schwinn, in the mid-70s, offered a bike called the Sprint with a similar seat tube.  Like many other Schwinns of that era, it was an extremely strange bike:  Save for the curved seat tube and the short (at least relatively) wheelbase, it was no different from the Continental.  At least the KHS was based on something that bore some semblance to a track bike.

 

Then there was the Rigi, made in Italy during the early 1980’s.  I never owned, but I had a couple of opportunities to ride, one.  It certainly lived up to its name:  I can recall few, if any, other bikes that were more rigid and transferred power to the rear wheel as much as that bike did.

 

I would be really curious to find out what effect, if any, the curved top and down tubes have on the ride of the Biria I saw today.  Whatever its ride, I don’t think its rider has to worry about stopping power:  It has a coaster brake on the rear wheel and a caliper brake for each wheel!