KenNC

I recently picked up a 1977 Peugeot PRN10E that requires some TLC, but noticed it came with 27 inch "Super Champion" rims. They seem to have an inner lip, so I put on some panaracer pasela 27 x 1 wire bead tires, crossed my fingers, and pumped them up to 110 psi. They seem to be holding on fine (bike isn't ready to ride yet). BUT, most other 27" rims that have come my way on bikes of this era don't seem to have an inner lip, and I don't inflate anything beyond 80-85 psi. Are the Super Champion rims true clincher rims that can take tire pressures like modern rims? And, when did rims with an inner lip like this start to appear?

Just remembered a discussion of Mavic Module 3 rims here: Were Mavic "Module" rims the first double-walled clinchers? Maybe these were in competition with each other?

Still don't quite understand why there would be any market at all in the 1970s for rims without this feature....

thumpism 

Depends on which Super Champ rim, the wider #58 or the narrower Gentleman, but both can take the pressure if the tire can.

dddd

Clincher rims that are made to consistent sizing tolerances don't need any bead "hook" feature to retain wire-bead clincher tires.

The popular Super Champ clincher rims were a "twin-hollow" (but other wise single-walled) Model 58 touring rim measuring 22mm wide externally and a racing-style, double-walled "Gentleman" model, and both featured bead hooks. Earlier models may have smaller bead hooks but I've used even these with folding tires with no problems.

A 1" or 25mm Pasela tire measures about 26mm wide on an average-width rim, so I run just 75psi in them (though I weigh only 145#).
Mine are wire-beaded on straight-walled rims (no hooks).

The Module 3 rim was like a Gentleman rim having 2mm added width so was double-walled. Very hard rims to find btw.

3alarmer 

...the bead hook ("inner lip") thing seems to have evolved over time. I have had Super Champion rims that have a sort of half hearted bead hook, and some older ones that seemed to have none at all. At one time, it was pretty difficult to find a clincher tyre that was rated for more than about 70 psi. (At lest in my personal experience.) So given those tyre capabilities, it wasn't such a big deal.

Araya rims are the same way. But I have no idea when the historical break point is.

I like to ride my tyres at full inflation pressures, because I'm large and heavy. When I get rims that lack a bead hook, I just routinely relace them to modern box section rims now. IME, if your tyre stays on the rim at whatever your current static inflation pressure is, it will say on when you ride as well. My blow offs have all occurred as I was inflating the tyre/tube. Makes a remarkably loud bang.

plonz 

I have 700c Super Gentleman clinchers on my Tempo with 25mm folding tires. Run 110-120 PSI with no issues.

The Tempo routinely sees high speeds. Hoping this bead seating business is the stuff of old wives tales.

steelbikeguy

The Super Champion model 58 was around in the mid 70's (and maybe earlier?) and had hooks to retain the bead.
I recall using these with 27 x 1 1/8" tires that took 90psi. Can't imagine using higher pressures, unless using narrower tires.

an illustration from the Cyclo-Pedia catalog of the era...




Steve in Peoria

T-Mar

The hooks or small beads on the inside of the sidewalls of wired-on rims are primarily to aid the seating and retention of foldable tyres. The Kevlar cords encased in the beads of a folding tyre do not hold the round shape as well as the steel hoops of traditional wired-on tyres. Consequently, without these hooks, folding tyres would be more prone to not seating concentrically and blowing off the rims.

When the feature was introduced in the mid-1970s, it was typically used primarily on 700C, box section rims which in turn were used on on primarily mid-range bicycles, where consumers where anxious to have performance approaching tubulars but without the inconvenience. There was also a smaller grand touring market which liked the convenience of compact spare tyres.

They were not used on entry level bicycles in the mid and late 1970s because of cost. Consumers buy entry level bicycles because of their low price. In large, entry level consumers are not concerned with performance and carrying spare tyres, The expense to include such a wheelset would put a company at a cost disadvantage in comparison to their competition. The feature would eventually trickle somewhat downstream but only after the R&D, tooling and other costs associated with new product introductions had been paid off.

Kabuki12

I have three or four sets of these , most of them are Gentlemen style and I run a 1 1/4” wide on the 27” wide non Gentleman at about 85-90 lbs and the 700c x 28c I run 95 on the rear and about 85 on the front . I have never had an issue . I am tall and weigh 155 and some of our roads are far from nice but no rimming at all . I like Pasela Panaracer tires or Bontrager Race Lite.

tkamd73 

I’ve got a set of Super Champion Competition Gentleman rims, shod with Continental Supersport 1/14” tires. 90 psi rear, 80psi front, lots of miles, no issues.
Tim

1989Pre 

I'm riding on Super Champion Modele 58's, 40H rear and 32H front. The tires are 27x1" Raleigh-branded IRC Roadlite gumwalls and I ride them at 100 psi, which is their maximum. No problems so far.

SurferRosa

Why not factor total weight and tire width to determine road tire pressure?