Tires with tan sidewalls - structural integrity difference?
 

Is there any pros/cons other than aesthetics coming with "classic" tires with tan sidewalls vs all-black ones?

It's mostly aesthetics today.

BITD, more purer rubber compounds tended to be the most flexable and supple. So they worked better for sidewalls that needed to flex. Better being a tad less rolling resistance than tires where the sidewall were pretty much almost the same rubber compounds as the tread which were black from the carbon and stuff that was used to make them more wear resistant and stronger.

Any differences today are probably many times more minor than they were in the 60's and 70's of the last century.

If any are claiming more suppleness or less rolling resistance because of their tan sidewalls, I've not noticed that. So for me it's just a aesthetic issue of what you like or what you think others want to see when they look at your bike.

My Rene Herse 650x42 Babyshoe Pass feel like floating on air! A ride over bad pavement feels like it’s smooth pavement. I believe tan sidewall tires are not all created equal

That's because they are the best tires in the world! Tan sidewalls might have specific qualities on other tires, but at least on the Rene Herse tires they're strictly aesthetic.

"The only difference between the black and tan sidewalls is the color. It’s only the rubber that is tinted differently – the casing underneath is the same." https://www.renehersecycles.com/rene...-right-for-me/

In practice there is no need for there to be a difference. You can formulate the rubber compounds to have the same properties with either carbon black filler or not. Black sidewalls will be a bit more resistant to UV degradation, but if you are riding so little that your tires fail due to sunshine instead of wearing out then you're not in this conversation.

I believe I had found some specific model of tire where it came with both "classic" (tan sidewall) and regular (all black) version and the sidewall one had a note to it that it was not tubeless ready, but I cannot backtrack it anymore and of course I can't know if the manufacturer specifically for that model chose different compound for the sidewalls other than skipping the "black" components that made it be less suitable for tubeless.

They used to be called gumwalls, maybe because we were supposed to believe the sides were pure gum. My guess is that they have had mineral fillers all my adult life.

On a commuter bike that spends its days outside in the sun and weather and gets ridden in the rain routinely, the tan sidewalls go dingy grey and they start to crumble sooner than black sidewalls. If your commute is more than a few km though, you will wear both tires out before they fail from sidewall degradation. If your commute is short or you insist on a clean look, use blackwalls.

I wonder if disc brakes help to keep tan side walls from going grey. How much of the grey is aluminum residue from braking in the wet?

oldschoolbike

Yes, when used in wet weather, rim brakes make tan tire sidewalls look grungy. Disc brakes avoid this issue, which is one of the few good things I can say about them...

I've got a 26x2.3" set of the Rene Herse Rat Trap Pass tires, in their Endurance tan casing, with a lightweight protective puncture belt, 500g. As you say, it's a bit like floating on air. Smooth and comfortable, yet precise handling (for a "fat" tire) and seemingly bomb-proof (so far, over a variety of normal urban street crud and mess mixed dirt/gravel/pavement surfaces. A little spendy, compared to most tires, but I think they're worth the ride quality.