Bike Forums - 27 Paselas sizing/other options

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I use the Gatorskin 27" tires on my tandem. They are ample in width so can be run at a somewhat more dirt road-friendly lower air pressure.

These are a reliable, long-lasting tire. Not cheap, but you get what you pay for and you need strong tires on a tandem.

Quote:

Originally Posted by jefnvk (Post 17836843)

OK, thanks! Not too sure on the guess and check system, but as a bigger (as far as bikes go, 205#) guy, not too sure I want to roll on 1 inch tires either :) Maybe Ill give the 1 1/8 inchers a try on my next Niagra order. I picked up a cheap Le Tour III at the Salvation Army today that I don't want to put much money into but that could use new tires, so at least the 1 1/4 inch wont go to waste!

FYI-in my experience the 1 1/8 Paselas measure between 27.5mm and 28mm depending on the rim width. Personally I like the 1 1/8 the best but they may not be for everybody.

Quote:

Originally Posted by trailmix (Post 17843916)

FYI-in my experience the 1 1/8 Paselas measure between 27.5mm and 28mm depending on the rim width. Personally I like the 1 1/8 the best but they may not be for everybody.

My other (and only one I've had for the past 15 years) bike has 1.95" slicks (and prior to that 2.25" knobbies), so I really have no idea what is for me :)

Quote:

Originally Posted by crank_addict (Post 17843335)

^ To be fair, my concerns are with a tandem and limited selection for 27" application. Gumwall for style points. I mentioned some of the problems in another thread so won't repeat too much here. The longevity issue is not talked much by test / journalist for heavy weight usage and sidewall flare out. Those bulging sidewalls are getting an extra workout.

So the typical answer by most is to further inflate, in this case, over the spec rating.

Add the problem of an overinflated clincher on a hot ambient day, brakes that work extra hard, creating more heat and to the tire. I find it difficult to believe this type of situation is going to be easy on such tire. Those sidewalls have a shred or burst point but even if they hold, it can't help in longevity. Its like driving your car with over inflated tires trying to compromise for a large load. That tire is going to run hotter and wear out quicker.

Actually, tires run hotter when underinflated wrt load because of the extra sidewall flex. Overinflating (within prudent limits) reduces the heat problem, and using larger tires is the best solution because the load-carrying capacity goes up. I run 38mm tires on my rando/touring/commuting bike, and they have an easy life because I weigh about 155 lbs and never put a lot of extra weight on the bike.

Quote:

Originally Posted by ThermionicScott (Post 17844579)

Yes, for the cars and trucks, higher pressure reduces heat buildup, so it should be safe as long as the max-pressure limits of the tire are respected.

But I think crank_addict was mostly speaking of how a tandem might overheat it's tires, heat that comes from braking, not from the tire's rolling resistance.
So a lower pressure might well be the safer choice when descending on any heavy bike with rim brakes.

I've owned my truck since 1989, and one of the neat things about such a long stint is that I know from experience exactly what tire pressures front and rear will give flat, even tread wear over the life of the tires.
I figure that such level contact of the tread on the road (my truck gets used almost exclusively on the highway) is probably the safest overall since it takes actual loading into consideration. Mostly though I am just trying for maximum tread life.
BTW, the Isuzu-recommended F/R tire pressures are about 2psi lower, though the pressure usually has dropped that much by the time I top up the pressures.

Quote:

Originally Posted by dddd (Post 17846020)

That all makes sense, but I still can't figure out how it's an argument against wide, supple tires. Perhaps I'm misreading crank_addict's post, but I would expect that bigger tires would be an especially good thing on a tandem, as you could inflate them below their max (but still enough to support the load) and have plenty of margin for the extra pressure that comes from descending with rim brakes.

Quote:

I've owned my truck since 1989, and one of the neat things about such a long stint is that I know from experience exactly what tire pressures front and rear will give flat, even tread wear over the life of the tires.
I figure that such level contact of the tread on the road (my truck gets used almost exclusively on the highway) is probably the safest overall since it takes actual loading into consideration. Mostly though I am just trying for maximum tread life.
BTW, the Isuzu-recommended F/R tire pressures are about 2psi lower, though the pressure usually has dropped that much by the time I top up the pressures.

Thank goodness we don't have to deal with bias-ply vehicle tires anymore -- radials are so much more forgiving. I've been running the pressures on my Subaru well above the door sticker for improved fuel economy and tire wear is still pretty even as far as I can tell. :thumb: