Now Brian,
A real constructeur like yourself might want to think back about Rene Herse or Alex Singer during the war under occupation when electricity was rationed and between raids for contraband components were hacked out by hand.
A modest 75 tooth chainwheel could be plotted out on a suitable plate on aluminum alloy and cut by hand, think like well, much rounder than biopace! Easier than flowery lugs but for each tooth, more work. You could even drill and press in chain rivet pins as ramps for the custom touch.
Just shape the teeth with a drill (a drill press is best) and hand file.
Naturally, I didn't need to make this up. Igor; our new old stock bike mechanic from Georgia (sic - former Russian Georgia) comes from stout stock which with bicycle parts shortages ever since 1917 or so has been making bicycle parts on an as needed basis apparently since birth. He is very out of touch with modern parts but show him a 30 year old magazine with new products featured and he'll explain in terrible broken English how he used to make those a few years ago; "Huret Duopar's, front and rear".
HE's the worst packrat. I caught him brazing a customers broken brake cable back together the other day. I told him to change it and he did, then salted the brazed brake cable into his old bag to take home. I think I hurt his feeling as he kept saying, " it good work, good work". He hot patches skinside tires, replaces entire valve bases in tubes. All he needs is a little flame and some talc. He was doing this a week before I realized we have stopped selling tubes and tires on repairs. And spokes, you get the picture. He doesn't understand why we don't just fix all the bent twisted derailleurs in our spare parts bucket. (We have tried)
I discovered the chainwheel thing after he discovered a 60T chainwheel rumbling round the shop and asked if we had anything bigger. The next day at lunch he was drilling away on this big alloy plate. It's butt ugly but it works. He rides a 75x16 fixed now. He seems to stand a lot.
Another creation yet to be named is a crank he made. He took an old Sugino crank and 3 x 53 chainwheels and then drilled and bolted them to the outer chainwheel and crankarm in an equally spaced triangular pattern to make one very large chainwheel. They had to be reinforced and he's working on the chainguide as the chain ramps between sprockets by hey man, this is impressive to the lay bike guy; and let's don't take about impressing small children.
Highest regards,
Gilbert "Talc is cheap, shall Igor whip up a creation for Brian" Anderson
The North Road Bicycle Company your bicycle outfitter 519 W. North St. Raleigh, NC 27603 USA ph toll free in USA :800/321-5511 Local ph: 919/828-8999 E-Mail: cyclestore@aol.com
In a message dated 7/6/02 12:07:18 AM, davebohm@cox.net writes:
<< These guys in England can make any ring you need. Can you say 110 tooth. Yeah baby! I plan to use them for some massively impressive chanrings on a future tandem.
http://www.argonet.co.uk/
Or Highpath Engineering.
Take it easy.
Dave Bohm
Tucson (way hot)Arizona
----- Original Message -----
From: Brian Baylis
To: Grant McLean
Cc: classicrendezvous@bikelist.org
Sent: Friday, July 05, 2002 8:28 PM
Subject: Re: [CR]giant chainrings
Grant,
Thanks for the tease. Let's hear some numbers! How big is the largest?
What bolt patterns are available? Talk is cheap, I want to know what he
has.
Brian Baylis
La Mesa, CA
I've got to play tonight; I'm out the door now. When I get back I expect
to hear that you guys up there can top 70 T. >>