Showing posts with label Bianchigirl. Show all posts
Showing posts with label Bianchigirl. Show all posts

20 March 2011

Twin Tubes, Again

Slept late but still got out for a late afternoon ride.  Along the way, I saw someone riding a bike I haven't seen in a long time:




If it looks like the seat tube swallowed up the rear tire...it did, sort of.  That's because the seat tube isn't a tube.  Rather, it's a pair of parallel tubes, much like what one finds in place of the top tube on a mixte frame.  On this bike, the rear tire actually runs between the twin parallel tubes.


I didn't see this exact bike.  But I saw someone riding one like it.  Like the one in the photo, it was a track bike, which is the sort of bike on which this frame design seems most appropriate.


The idea behind it was to make the chainstays and wheelbase shorter, which gives the bike more torsional stiffness while making it more responsive and its handling more sensitive.  It seems that every generation or two, someone pushes the idea that stiffer is better.  And the last time that idea came around, I bought into it.  After all, I was still a guy back then. So what  did you expect.  Stiffer is better indeed.  


Anyway...before I get myself in any deeper, I'll tell you more about the bike.  I actually got to ride one when I was working in a shop about thirty years ago.  It was indeed the stiffest and most responsive bike I'd ridden up to that time.  But it was so sensitive that if you sneezed, you'd probably end up across the street.


The funny thing about Rigis was that the road models seemed to be even more extreme than the track models.  Maybe that was because the shortness of the stays and steepness of the frame angles seemed even more unusual for a road than a track bike.  Look at the photos on Bianchigirl's page to see what I mean.


Back then, we all thought the Rigi was some radical new design.  Turns out, an English builder had the same idea, and for the same reasons, before World War II:





To learn more about this late 1930's Saxon bicycle, check out Hilary Stone's article on Classic Lightweights UK, a beautiful and fascinating website for the bike enthusiast.


I guess in another decade or so, someone'll revive the design.  Plus ca change, plus la meme chose.