If you read The Dancing Chain it seems that track gear has historically held to traditional standards, while derailleur equipped road bikes have changed to narrower, lighter and more flexible chains.
Per The Dancing Chain, in the 19th century and at the beginning of the 20th century, most bikes used inch pitch chain. It isn't really stated, but perhaps this was already 1 x 1/8, which survived until the 60's on track gear. In the early decades of the 20th century, 1/2 x 1/8 chain began to become common. This was no doubt driven by the need for a more flexible chain to allow the new derailleurs to operate more smoothly. However, we know that the TdF and some other races banned derailleurs for decades. Does this mean most racers continued to used inch pitch gear on the road, even long after 1/2 x 1/8 was adopted by tourists?
Soon after WWII, 1/2 x 3/32 chain began to become common. This was no doubt driven by the increase from 3 FW cogs to 4 and 5, which needed a narrower and still more flexible chain. I've not owned a coaster brake or a three-speed bike since my teens, but my recollection is that these stayed with 1/2 x 1/8 chain, as they did not need the greater flexibility. BMX bikes would later use it as well.
A question occurs that perhaps Jan can answer. I believe in BQ, he says that the Technical Trials awarded point for more gears and that this resulted in machines being entered with 5 or even 6 speed FW's, I believe even before WWII. Did these advanced prototype machines then have 1/2 x 3/32 chain even before WWII?
It seems that 1/2 x 1/8 chain gradually began to replace inch-pitch on the track soon after WWII. That's still the standard, though one does now see 3/32 track gear. I presume that the 3/32 stuff would be used in events like pursuit, while most sprinters probably stay with 1/8.
On thing does puzzle me, as my "modern" equipment is limited mostly to the 1999 Chorus gruppo on my wife's lugged steel Bianchi TSX/UL, one of the last lugged steel frames Bianchi made. If 3/32 chain still actually 3/32 wide? Starting with the SedisSport, 3/32 chain, which I think is measured at the outsides of the outer links, where the chainwheel teeth would engage, became narrower in sections between teeth. This made the SedisSport and its immitators the preferred cahins for 6 and the 7 speed FW's. As the rear cogs have gone from 7 to 8, 9, 10, and 11 we talk about narrower chains. So is it still actually 3/32 at its widest? Or has that now been reduced a bit? If it's still 3/32, how does one get clearance for the chain between 11 rear cogs? I doubt the greater rear frame spacing is the complete solution. Are the cogs themselves thinner?
This all brings up one of my retrogrouch peeves agains modern equipment. I personally consider 11 rear cogs on a derailleur bike ridiculous and unnecessary. One "advantage" of these clusters has been to make 11T cogs routine. But I doubt any except pro racers really get any advantage from a 53 x 11. And in the middle of the range, many gears are duplicated between the chainrings, especially for a triple. Of the theoretical 33 gears on a triple with an 11 cog cluster I doubt there are much more than half that number of usable gears distinct enough to make a difference. So we now have more fragile chains and more wheel dish resulting in weaker and/or heavier wheels all for a lot of extra gears that are either unusable or duplicated. I think we reached to point of diminshing returns at about the 7-speed rear cluster and have now gone past the point where derailleurs make sense. If anyone really thinks they need more than 7 gears on the rear, it seems to me the 14 speed internal gear rear hubs now available make more sense. These don't need massive wheel dish or narrow fragile chains.
Big Spring, Texas, USA
> From: M-gineering <firstname.lastname@example.org>
\r?\n> Subject: Re: [CR] Dumb track bike question
\r?\n> Cc: "CR List" <email@example.com>
\r?\n> Date: Wednesday, November 4, 2009, 6:57 AM
\r?\n> David Bean wrote:
\r?\n> > I don't see why a 1/2" chain should be anything but
\r?\n> heavier than its 3/32"
\r?\n> > equivalent. It has the same side plates, but
\r?\n> shorter pins and rollers (with
\r?\n> > the same diameter as the wider chain). Yet the
\r?\n> heavier chain and its
\r?\n> > somewhat thicker cog and chainring seems preferred by
\r?\n> > weight-weenie track racers. Am I missing
\r?\n> > David Bean
\r?\n> > Arlington, MA USA
\r?\n> > beandk at are-see-enn dot com
\r?\n> Thicker chainrings are much stiffer and stronger, and you
\r?\n> don't need a chain optimized for derailling.
\r?\n> Min weight is 6.8 kgs, so weightwatching is fairly
\r?\n> -- mvg
\r?\n> Marten Gerritsen
\r?\n> Kiel Windeweer