Revracer

I have read a few posts about Weinmann single wall 27x1.25" hookless rims and concerns with blown tires, losing true, etc. These rims are original on my 1973 Raleigh Grand Sports project and if they could be solid performers, I will throw the wire bead Pasela tires on them and ride. Most of the time I prefer 700c and have no problem building up the Normandy high flange hubs up with H Son Plus TB14 or Sun M13ii rims, but these rims actually look OK, have a nice profile and would be a nice original look.

Anyone riding these rims regularly with Pasela wire bead with good experience?

Kovkov

dddd

As I mentioned, there are similar but different versions of such rims that did/didn't cause blow-off below 80psi, and with different wire-bead tires having virtually no effect on this.
Continental wire-beaded tires do seem ever so slightly tighter-fitting in my limited testing, while a wall-to-wall layer of thicker rim tape can make a big difference. The problem can be getting any rim tape to lay in place without wrinkles and gaps away from the inside walls of the rim, which allows the tire bead to move about too freely in many cases. I have custom-trimmed the wider Velox rim tape to achieve this, it was quite painstaking but it did work well and allowed about 15psi increased tire pressure in my particular case as I recall.

Test-fitting on a bare rim might not reveal the problem, as spoke tension of a built wheel reduces the diameter noticeably in terms of tire fit.

Revracer

Yep, that description aligns with what I had read that is leading me to say replace the rims. It is not that a compromise cannot be reached, but still gives limited assurance. The tires on the rims as bought were a Specialized 27x1.25 wire bead rated to 100psi. I had maybe put 90psi in them and rode 30 miles and no issues. Of course when removing one tire to inspect, the bead was quite stuck to the sidewall and flaked away when removed.

While I decide what to do with the original wheels, I am riding a modern set of 27" FG/SS wheels Weinmann RM19 with Kenda K36 that have the high center ridge, are quite hard and weigh over 500g each. I rode these same wheels on a Ross Utopian while I tried to decide how to build that bike and almost discarded the bike. I now ride Mavic MA40 w/ Gravelking 700x32 on the Ross and it is a pleasure and reliable (I use MA40 on at least 2 other bikes).

dddd

If you had tires on them at 90psi, I don't believe that you will have tire problems going forward.

The single-wall rims are not the strongest, but with decent tensioning at even 75kg uniformly, they should be fine for any usage short of trauma.

crank_addict

No worries.

I'm using a pair, probably like Kovkov has. Stamped Weinmann, 700c also called for 28 inch. 50's era five or seven sided, zeppelin style. Using very old Michelin 28 all white rubber - wire clincher of course.

palincss

Not to be needlessly picky, but the size was never 27 x 1.25", it was 27 x 1 1/4". Decimal vs fractions makes a huge and significant difference when it comes to tire sizing, and the general rule is the decimal is never the same size as the fraction.

Lascauxcaveman 

I had a set of those rims and tried a pair each of Paselas and Kendas. I can't remember which ones held better, but I remember one was more solidly set on the rim at 85 psi and the other was kinda iffy at 75 psi.

Which is just my way of saying all 27" rims and (especially) all 27" tires fit a little differently. Some are tighter, some are looser. So to fit with confidence at a pressure you like, you kind of have experiment to decide if the combo you have worth the risk.

I've found on tire/rim combos with a sorta loose-goosey fit (such as, the tire goes on easily with no use of tools) it helps to pump the tire up to 5-6psi, then sorta smush the bead down where it seems to be riding high, and lift where it's riding low; sorta massage the tire into place so it's evenly dispersed around the rim. then pump it up to about 30, check it again, then pump it up all the way.

Of course, its easier to just a have good snug fit tire/rim.

76SLT 

I'm using 27 ×1 1/4 Pasela's on my 73 Grand Sports with Weinmann rims, and haven't had a problem.

badger_biker 

I'm not sure if they are the same as what the OP has but my Weinmann rims are the concave ones on a 1884 Miyata. I had issues blowing off and getting a good round seat with Schwalbe Marathons at around 75-80 psi. I switched to 1 1/4" Pasela's and have had no issues with blowing off at the same psi.

jonwvara 

Exactly my situation, except that my Gran Sport is a 1976. I inflate the tires to about 70 psi. It gives a great ride. I've ridden it a lot on both dirt roads (where it excels) and on pavement. I did re-spoke it with stainless steel spokes a couple of years ago, because the originals were getting pretty tender.