72SuperSport

Having some issues with the original Weinmann aluminum 27 x 1 1/4" rims. Even though they are stamped with that exact size, in truth they are less than an inch across the width of the rim, more like 7/8". Been losing rear tubes as the tires I am using don't seem to want to bead up right. Have to be really careful beading and inflating them, and I like to run my tires right at their max pressure - 90 PSI. Usually use talc on the inside of the tire to let the tube find its own center when inflated and prevent pinching. Been using Walmart specials - Bell Streetsters and their tubes, which work really well on my '84 Varsity with stock steel rims, that are closer to 1 1/4" across. Not sure if the issue is the tires, the tubes, or the rims. Considering going to a good Continental tire. I ride mostly asphalt and concrete bike trails, sometimes 50-70 miles 3 - 4 times a week, normally 25 miles 4x a week. Rim beads are clean, wire brushed, spoke guard strip not too wide.

oddjob2

Wire bead tires. Try Panaracer Paselas for a skinwall or Vittorio Zaffiro if you want all black. Both around $20 each.

Metacortex

That is par for the course, 90psi is *way* too much. Those original Weinmann rims have straight walled sides, while pretty much all modern tires are designed for rims with sides having hooked beads. This means that you cannot run more than about 75psi without blowing the tires off the rim. Another option would be to replace the rims with hooked bead versions, after which you can run higher pressures. More info here: https://www.bikeforums.net/classic-vi...ure-tires.html

Number_6

I blew a tube filling to 90+ the day after I bought mine. I watched it bulge while i was struggling with getting my pump off, but was too late. The PO had put new Kendas and tubes on it, fortunately the tube patched ok. Not only was there that, but the front rim was a steel Schurmann. Probably a quick fix at some point after an accident or theft. With the steel replacement rim and the propensity to blow tubes, I also view the SS as a bit of performance job, since it has quite a bit of potential with mods. So, I've elected to get a pair of Weinmann LP 18's that'll clinch. I'm running about 70 in the tires right now and the riding is pleasant, but I think I'd do a lot better with a lot more PSI. I'll keep the stock aluminum rim though- if I can scrounge a mate for it, it would make a nice replacement for my pretty original Suburban. Better braking, period look and I might save a couple grams in weight...

dddd

Don't be fooled by the feel of hard tires, they don't do much to reduce rolling resistance, only feeling faster because of the high-frequency buzz coming through.

Pressure should be proportional to rider+bike total weight. I run 1-1/4" tires at just 60psi for my ~175lb bike+rider weight, and run the 1-1/8" tires on my Supersport at just 75psi. These are tires that measure about 26.5mm wide on the ~23mm-wide Weinmann rims.

These particular Weinmann rims are exceptional in terms of their low blow-off pressure tolerance, most if not all other straight-wall 27" rims will allow much higher pressures with any wire-bead tire. My other 1971 Supersport has slightly different Weinmann 27" rims which handle at least 90psi without the tire bead lifting up, but I don't want to ride at such high pressure. Lower pressures give longer tread life and maintain traction better over rough pavement or over hidden bits of gravel. Lower pressures also allow older tires to be safely ridden for a longer period of time without the risk of outer-ply failure.