Classic & Vintage - smooth-sided 700c rims?

Bikeforums.net is a forum about nothing but bikes. Our community can help you find information about hard-to-find and localized information like bicycle tours, specialties like where in your area to have your recumbent bike serviced, or what are the best bicycle tires and seats for the activities you use your bike for.
peripatetic
09-12-06, 01:03 PM
I've found some old wheels with Sansin hubs (6-speed rear cluster) and Weinmann concave, hookless rims.
Anyone tell me about these? Should I just chuck the rims and keep the hubs for lack of proper tires? Or are can I find low-pressure tires for 700cs?
Thanks.
silversmith
09-12-06, 01:39 PM
I haven't seen hookless 700s. Sure they aren't 27s?
raleigh_fan
09-12-06, 01:43 PM
I've found some old wheels with Sansin hubs (6-speed rear cluster) and Weinmann concave, hookless rims.
Anyone tell me about these? Should I just chuck the rims and keep the hubs for lack of proper tires? Or are can I find low-pressure tires for 700cs?
Thanks.
Those rims are a deathtrap! Don't ride them -- send them to me and I'll dispose of them properly! ;-)
I'm running 700c Concaves (yes, they do exist) on my Raleigh, and they've proven to be indestructible. I just put a set of Conti Grand Prix gumwalls on and they've been great. The tires were a bear to get on -- the bead is very tight. I run them at about 100 psi (the recommended pressure on the tire is 115). The tires say "Hook Bead Only", so I am emphatically not recommending you run those tires on those rims.... ;-)
peripatetic
09-12-06, 05:39 PM
Those rims are a deathtrap! Don't ride them -- send them to me and I'll dispose of them properly! ;-)
I'm running 700c Concaves (yes, they do exist) on my Raleigh, and they've proven to be indestructible. I just put a set of Conti Grand Prix gumwalls on and they've been great. The tires were a bear to get on -- the bead is very tight. I run them at about 100 psi (the recommended pressure on the tire is 115). The tires say "Hook Bead Only", so I am emphatically not recommending you run those tires on those rims.... ;-)
Wow, really? So no problems at all? I don't know if you saw, but there was a thread running about finding tires for hookless rims, and the consensus was that one has to use tires rated at 90 psi max, b/c those kinds of rims were made for lower pressure tires (a la old chrome wheels.)
Hmmm. I have a bunch of Contis, and I got scared off by the "Hook Bead Only" warning, but now I'm contemplating giving them a shot. So you've never had any issues with the things flying off, huh?
Oh, and yes, they're definitely 700s. The labeling is on the rim right next to the "Weinmann" label. Seem somewhat unique...
I don't know if you saw, but there was a thread running about finding tires for hookless rims, and the consensus was that one has to use tires rated at 90 psi max, b/c those kinds of rims were made for lower pressure tires (a la old chrome wheels.)
Oh I remember that thread. I was the guy in search of a tire for that 27" rim. They were aluminum although most may have been steel back then. It's had nothing to do with whether the rim was strong enough. The main problem was during inflation the tire would start to lift off the rim enough to allow the tube to get out between the tire and the rim and cause a blowout. If you are aware of this problem when you are inflating the tires you'll know what to look for. I have found if you find the right tire you can use these rims. It seems to me you can use any tire out there as long as you under inflate them. I think the best combination is to find a tire that you can get as close to the recommended PSI as possible without the tire starting to lift. One example I can give: I had one brand of tire that the recommended PSI was 105 but the max I could get in safely was only 70 PSI. This is fine if you want a tire that rides SSSSSLLLLLLOOOOOWWWW!!! Now a good example: I was able to find a tire with a recommended PSI of 95 and was able to get between 80 and 85 PSI in them safely "no lift". So the tires got good and hard.
Rolls FFFFAAAASSSSTTT!
There was a big learning curve for me. We all had to endure that thread and I had to kill two tubes and try a couple different tires.
Hope this will help,
J B
I strongly recommend using tires designed for 70 or perhaps 80 PSI on smooth-sided rims. The last time I checked, Harris Cyclery had some appropriate Continentals. I use Schwinn 27 x 1-3/8" knobbies on my UO-8; the sidewalls read 70 PSI, so I generally inflate them to 75 or so, never more than 80, and they have served me brilliantly.
Rabid Koala
09-13-06, 01:21 PM
I have used those rims and love them. I am going to soon build up another pair with Campy HF hubs. The ones I used previously had Michelin tires on them, no problems with them blowing off. I think, repeat THINK, they ran at about 95 PSI. The one salvation of the concave rims are that the braking surfaces and sides of the rim are not curved outward and hold the tires well.
I have used those rims and love them. I am going to soon build up another pair with Campy HF hubs. ...
If I had a set of those rims, I would do likewise. (I do have a beautiful pair of original Campag. HF Record hubs, ready to go back onto the 1960 Capo.)
raleigh_fan
09-13-06, 06:03 PM
Wow, really? So no problems at all? I don't know if you saw, but there was a thread running about finding tires for hookless rims, and the consensus was that one has to use tires rated at 90 psi max, b/c those kinds of rims were made for lower pressure tires (a la old chrome wheels.)
Well, no problems so far. The Contis have about 200 miles on them. The cheap-**** Specialized tires they replaced had about 800 on them. Neither tire showed any tendency to lift or blow off..... As always, YMMV!
peripatetic
09-13-06, 07:19 PM
But isn't it true that when 700c rims started getting common, the higher pressure tires and also hooked rims were getting common? Were these just made at that point before they started usind the hooked beads but after they started making 700cs?
huh.
Powered by vBulletin® Version 4.1.12 Copyright © 2013 vBulletin Solutions, Inc. All rights reserved.