Classic & Vintage - Weinmann concave rim

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View Full Version : Weinmann concave rim


kranz
08-21-04, 03:01 AM
I've been riding on old Weinmann "concave" rims with low flange normandy hubs for a while now. I quite like them, but don't really know much about them and am curious about the design of the rim. Was the concave design done for some special purpose or specialty? Comments from anyone familiar with these rims appreciated.

thanks,

kranz


phillybill
08-22-04, 06:03 PM
They were quite the rage back in the early 80's, the concave design was supposed to stronger than a traditional box design of the day. They are very solid rims, and had a good repuyayion on the race circuit.

Michel Gagnon
08-22-04, 08:30 PM
Agreed. However, today's designs are a bit better:

- Concave rims were single-wall; many newer rims have double walls, which make them stronger and less "twistable". A modern well-built wheel with 32 spokes is often stronger than a Concave with 36 spokes.

- Maybe others had them, but the Weinmann Concave rims had no hooks. It means maximum tire pressure was around 50-70 psi. If you try a modern tire at 100-120 psi, it's likely the bead will get off the rim.

- And a detail: it's hard to keep a Concave rim clean.


khackney
08-23-04, 07:12 AM
- Maybe others had them, but the Weinmann Concave rims had no hooks. It means maximum tire pressure was around 50-70 psi. If you try a modern tire at 100-120 psi, it's likely the bead will get off the rim.

Not completely correct. I have them on my Raleigh Competition and on my fixie. I use wire bead tires and regularly run 115 psi. I wouldn't use folders at any pressure on a non-hook rim. Just make sure that you don't have any rim strip lapping up on the inside of the rim where the tire bead sits. They were the original rims that came on my Raleigh and the tires on it the day I got it were over 100 psi. I know because I'm the original owner. ;)

These are very strong rims. Sheldon Brown I believe said it was the only rim that he could ride with a flat tire and not worry about hurting the rim. They are a pain to keep clean and shiney however.

teanga
08-23-04, 09:11 AM
ah, that perhaps explains it. Recently picked up an 78 Raleigh Competition with Weinmann concave rims. Tires on the bike were in good shape, so pumped them up to 100 psi and went a riding. Within two miles or so the rear tire went off the rim. Glad it was the rear. And these tires had wire beads. Suppose I should start looking for a set of wheels for this bike.

kranz
08-26-04, 11:37 AM
I've been riding on mine with Continental Ultra 3000 tires inflated to 100psi. I easily have over 1000 miles on them this season. Continental prints an ominous warning on their tires (even the 27 1/4") that they are not to be used on rims without hooks. Am I lucky that I haven't blown a tire?

photojtn
08-28-04, 10:20 PM
I have the concave rims on my Schwinn Le Tour Luxe since 1986, and still going strong. suntour sealed hubs and 3 cross zinc spokes very strong and has been very reliable. i'm running the conti tt 2000 (1 1/4) tyres.

mswantak
08-28-04, 11:23 PM
Funny this thread should show up again today; my '68 Motobecane has long-neglected Weinmann concaves, and I spent the best part of the afternoon confirming that along with any other faults, the cross-section makes them a royal b*tch to polish.

:eek:

dkastner
01-05-05, 02:15 PM
My last of the English made Raleigh Super Course Bikes came with Weinmann Concave 124-A rims. I put around 30,000 miles on them with Specialized Turbo S tires which are foldable kevlar bead tires with latex tubes at 120-125 psi. I then passed the Bike down to my son who was pretty hard on it and NEVER has a tire come off the rim. Did I beat the odds or did I just do a good job of making sure the tires were seated properly. I don't know.

pinerider
01-05-05, 05:43 PM
I'm another Continental Ultra 3000 user with my old Weinmann concaves (27"). I've been riding them almost daily since August at 90 psi or so, no problems whatsoever, other than a broken rear axle this week, but I can't blame the rims for that one!!!

TheRaleigh
03-11-08, 09:55 PM
Sorry to raise this from the dead, but. I ride an old Supercourse with Weinmann concaves, and have had no problem running tires at 90-100psi, so long as they dont have kevlar beads.
These rims are very very strong, yes. I've had spokes break with very little loss of true. However, they are VERY HEAVY.

poprad
03-12-08, 12:53 AM
Sorry to raise this from the dead, but. I ride an old Supercourse with Weinmann concaves, and have had no problem running tires at 90-100psi, so long as they dont have kevlar beads.
These rims are very very strong, yes. I've had spokes break with very little loss of true. However, they are VERY HEAVY.

Ditto, my new-to-me 79 Comp GS has 'em and I love 'em. Run over 100 psi all the time; no problems whatsoever.

http://farm3.static.flickr.com/2195/2303338858_ef3a60638f_b.jpg

http://farm3.static.flickr.com/2108/2302541629_dc7772a41e_b.jpg

pastorbobnlnh
03-12-08, 03:39 AM
I have a set of the Concave rims (700c) pictured in the post above. They are in good but not new condition. If any one is interested in them, PM me.

Four C&Vers have PMed me so we're working on arrangements! Thanks for the interest!

Mhendricks
03-12-08, 11:47 AM
I have a set of the Concave rims (700c) pictured in the post above. They are in good but not new condition. If any one is interested in them, PM me.

Four C&Vers have PMed me so we're working on arrangements! Thanks for the interest!

I also have a set of these on Weyless Hubs if anyone is interested and I have an extra unlaced rim to go with it. One of the Weyless hubs' skewers might need replacement as the threads are not that good. I could have one machined if you're really interested.

http://i149.photobucket.com/albums/s48/mixtemike/EBAY/IMG_2243.jpg

http://i149.photobucket.com/albums/s48/mixtemike/EBAY/IMG_2245.jpg

http://i149.photobucket.com/albums/s48/mixtemike/EBAY/IMG_2244.jpg

Rabid Koala
03-12-08, 01:21 PM
Before I knew I couldn't do it, I ran Michelins on concave rims with pressure around 100 psi with NO problem whatsoever. They held the tires just fine.

bibliobob
03-12-08, 01:38 PM
My dad had a 70s Windsor Professsional with Weinmann concaves. In the late 80s, I was riding it and hit a Honda Accord head-on, at about 20 mph.

I demolished the hood of the honda, bent the downtube of the Windsor, and gashed my thigh pretty well.

The Weinmann was just fine. Not even a wobble.

ricohman
03-14-08, 06:24 PM
Does anyone know if the 700C rim came in a 40 hole? I am looking for one but maybe I am wasting my time if it only came in the 36 hole variety.
I do know the 27 inch came in the 40 hole as I have one.