At 9:34 PM -0400 5/8/07, Peter Weigle wrote:
>Harvey, There would be no need for the chain loop if the freewheel
>stayed on the bike as the chain would stay on the cog.
There were special hubs with freewheels that did stay on the frame, similar to Cinelli's later Bi-Valent design. This Herse
http://www.vintagebicyclepress.com/
is equipped with that feature, but you can't see it in the online
photo. Indeed, you don't need a chainrest with that. The bike was
featured with a full photo shoot in Bicycle Quarterly Vol. 3, No. 1.
>
>Greg Reiche pointed us to the picture in the Data Book page 140, and
>it shows there is a "wingnut" that passes through the washer and
>then threads into the hub. It shows the hub with freewheel being
>removed from the same dropout. Good reference Greg!
The "washer" in fact is a tube, and is filed so that the axle (what remains of it) rests against the top of the tube when you insert the wheel. That way, you just put in the wheel, and it's already aligned with the dropout hole for the "wingscrew." For details, see
http://www.vintagebicyclepress.com/
especially drawing No. 3. I suspect the "Data Book" drawing is the same, taken from this Singer catalogue.
Bicycle Quarterly Vol. 1, No. 1 featured a very similar Alex Singer
with photos of the chainrest and disassembly mechanism. The alignment
of all these features must be spot-on to work properly...
>
>Most guys I know would just pick the damn chain up with their
>fingers and put it back onto the cog,,, then wipe the grease onto
>their shorts,,, thats why the're black, right?
>Must have been more civilized back in the old days.
It's not so easy with a touring derailleur, which wraps around the chain on three sides, especially with wingnuts and thus long axles. There is nowhere for the freewheel to go, and without a chain rest, you wrestle with the chain for several minutes until you get it between the axle and the dopout and can take the wheel out. Same procedure when you put it back in. The Nivex guys found the chainrest solution to the problem, just like they found solutions to pretty much every other problem with derailleurs.
(NOTE: I am not saying that Nivex invented all the innovations of their derailleur system. They did obtain a number of patents, but it is possible that some features had been used before, without finding widespread adoption.)
Jan Heine
Editor
Bicycle Quarterly
140 Lakeside Ave #C
Seattle WA 98122
http://www.bikequarterly.com