Showing posts with label component changes. Show all posts
Showing posts with label component changes. Show all posts

10 July 2013

An Old Conversion

In an earlier post, I wrote about the Schwinn Super Sport, a bicycle Schwinn produced from 1962 until 1973. 

At the time, Schwinn marketed it as a “lightweight” model.  It was indeed lighter than the Varsity or Continental, which were essentially ten-speed tanks.  The Super Sport featured a frame made of Chrome-Molybdenum tubing and most of its components, including the rims, were aluminum alloy.  One of the notable exceptions was the one-piece “Ashtabula” crank of the kind commonly found on cruisers, heavyweights and kids’ bikes.  (Some of those kinds of bikes, on which weight is no object, still come equipped with such cranks.)

However, it was possible to take a couple of pounds off the bike by changing the crankset.  At least one company offered a bottom bracket assembly that allowed the use of cotterless alloy cranks on frames made for Ashtabula cranks.  They seem to have been most widely used on motocross bikes; around the time that sport was developing, Gary Fisher, Joe Breeze, Tom Ritchey and other early mountain bikers were using crank adapters on old Schwinn balloon-tire bikes they adapted for use with derailleur gears.  (Most of those bikes came with single-gear coaster brake hubs as original equipment.)  I haven’t seen, or even thought about such a crank conversion in ages—until today.

This bike was parked, with a few other bikes that were being used for deliveries, outside a bodega/takeout luncheonette not far from where I live.  I spotted it on my way home from a lunchtime ride:



Unfortunately, as the bikes were locked to each other, I couldn’t get a better photograph.  But I think you can see how the bike was converted.



I’m guessing that this conversion was done some time ago, as the crank is a Sugino Maxy from the mid-1970’s that shows its age.  At the time, they were one of the least expensive cotterless cranksets made.  Many mid-level Japanese bikes—including the Nishiki International I once owned—came with the Maxy as standard equipment.

It wasn’t bad:  It was definitely an improvement over the cottered steel cranksets found on most European bikes in the same price range, or Ashtabula cranks.  On the Maxy (and other cranksets like the Takagi Tourney), the large chainring was “swaged” (pressed) onto the inside of the right crank arm, and the smaller chainring was bolted to it.

That meant, of course, that the outer chainring couldn’t be changed.  But cyclists rarely wanted to make such a change:  Outer chainrings usually had 50 or 52 teeth, and the smallest cog on most freewheels had 14 teeth.  (Thirteen-tooth cogs were still exotic items used by professional racers.)  And, it was believed, few people would ride enough miles to wear out the large chainring. 

Anyway, the Super Sport was probably the one full-sized, derailleur-equipped bike on which such a crank conversion made sense.  (The next model up in Schwinn’s lineup, the Super Sport, came with a Nervar or TA cotterless crankset.) 


Because the Maxy is of more or less the same era as the bike (and the conversion kit), it didn’t look out of place.  All of the other components, save one, were original.  The rear derailleur—an all-black Shimano Deore—is definitely an improvement over the Schwinn-branded Huret Allvit that came with the bike.  I couldn’t photograph the bike from an angle in which I could show the derailleur, but I think you’ll understand (and perhaps agree) when I say that it screams “replacement part” in a way the crankset doesn’t.

05 February 2011

Cranking (and Gearing) Up Arielle

So...How do you spend another dreary winter day on which the streets are still full of ice?  I know, ride a trainer or rollers.  I may just go out and get one or the other.  I used to ride rollers, back when I raced and when I told myself I was "going to get back into racing."  I know it helped to keep me in shape and improved my bike handling skills.  But it was boring, boring, boring!

So I spent today--part of it, anyway--modifying Arielle a bit. 



There was nothing wrong with her;  as I mentioned a while back, I didn't feel I needed the triple I had given her.  So I swapped the crankset for a "compact" double and changed the cassette (and chain, which needed it).  The gearing change allowed me to switch from a long- to short-cage rear derailleur and from a triple to a double front derailleur.


Arielle's drivetrain now consists of:
  • Sugino "Alpina" 170mm cranks with Specialites TA "Syrius" chainrings, 50 and 36T
  • Phil Wood bottom bracket with 108mm stainless steel spindle and rings
  • Shimano "Dura Ace 7700" (9-speed) rear derailleur
  • Shimano "Dura Ace 7402" front derailleur
  • SRAM 850 8-speed cassette
  • SRAM 890 chain
  • White Industries Platform Pedals with MKS steel toe clips, Velo Orange leather toe clip covers and Velo Orange Straps
  • DiaCompe "Silver" downtube levers.
I had been using the levers before the switch.  I like them very much:  They have a smooth action and feel good on my fingers.  I like the simplicity of downtube friction shifters:  After riding with Shimano STI and Campagnolo Ergo brifters for about a decade and a half, I came back to them about two years ago.

Interestingly enough, the same size bottom bracket worked with both the triple and the double.  Of course, that does not mean that you can get away with using the same bottom bracket when switching from one crank to another:  That depends on which model you're switching from and switching to, and on various dimensions of your frame.

I had been using the 50T chainring on my triple.  I decided to keep it because it gives me some gears that I really like.

Now all I need is some decent riding conditions.  I'm not fussy about temperatures, can stand some wind and don't even mind light precipitation.  But I'm not about to ride when there's ice everywhere.  Arielle deserves better than that!