Good idea David, I see exactly what you mean about the bulged side plates. That does make perfect sense as you describe the actual shifting and I can almost visualize the alternating wider openings of the bulged plates helping to simply dropping a hooked chain around the tooth...
I have a couple of spare silver Sunrace chains, so before I had even finished writing this e-mail, I have just tried one. Amazing. I can immediately see a dramatic improvement in shifting.
You the Man David!
Thanks Much! Bob Hanson, Albuquerque, NM, USA
David Snyder wrote:
Bob, Your PC-58 chain has straight-sided sideplates that don't really reach out far enough to go fully over the teeth under certain conditions. I've also had this problem with the previous Sedisport chains on Maillard Helicomatic cogs. Very annoying, this unwanted, sudden freewheeling.
Switch to a chain with bulged-out outer sideplates. Pioneered in the modern era by Shimano with their Uniglide chains, and available today in their HG-91 model.
Others, including KMC, Sunrace, YBN (IRD) and SRAM (with their latest 851/951(?) models), have also adopted this design, but most super-narrow (9 & 10sp) chains use flush pins and beveled, but not bulged-out sideplates.
The Shimano-style chains also grab vintage chainring teeth more aggressively for easier shifting up front. Shimano's current chains are also definitely among the very longest lasting.
The Sunrace 8-speed chains come in a bit narrower than Shimano's HG-91 and are my current favorite for friction shifting because they are less finicky about precise shift lever position. These attach traditionally with normal press-fitted pins, are inexpensive, seem to be long-wearing and have an attractively polished finish.
David Snyder preferring Uniglide sprockets above all others in Auburn, CA
Bob Hanson wrote:
> I've noticed recently that a new SRAM PC-58 chain tends to "Hang" - riding
> atop the cogs of an old Maillard compact 6-speed freewheel. These cogs
> featured the familiar symmetrical "notch-top" teeth designed to help lift
> up a
> chain. Maybe not too helpful a design, but they nevertheless had been
> produced
> for many years. So, I thought I had just suddenly begun shifting very
> sloppy.
>
> However, examining the chain and freewheel carefully, I noticed that the
> chain's outer plates are actually tapered considerably. This creates a
> clean
> knife-blade like fit into the teeth of the cogs. This was not an issue
> on the
> old Sedis chain which I replaced - which had side plates which were not
> beveled, and it is not an issue with old Regina Oro or Corsa chains which
> have
> just flat side plates.
>
> I love the Sram 8-speed chains which I now use on most bikes - even with
> 5-speed freewheels... but, definitely not with these cogs. So, can
> someone
> please recommend a good modern chain to use on this style of freewheel?
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