Friday, August 28, 2015

"Because so much is riding on your tires"

Above: a few of our favorite tires

You might remember that slogan used by Michelin for their automobile tires, but it's very true: Pretty much everything is riding on your tires and on a bicycle that's a pretty small "footprint" indeed.

Larry's always amazed at the rituals involving cyclists and their tires. We're going to offer some advice and try to bust a few long-standing myths in the process. Ready? Read on.

Let's start with inflation and pumps. Many of our clients seem perplexed by our choice of tire pump, the venerable SILCA, especially with it's simple push-on Presta chuck. Click HERE for some great information directly from the new owners of this venerable brand, but understand that a couple of "modern" pump makers at one time were CycleItalia Official Suppliers, These pumps were just fine in the ease-of-use category but failed miserably in the day-to-day use and abuse these pumps face, so we'd always fall back on an ancient Silca we had for our personal use, one still in use today. We eventually purchased a few more Silca pumps and they've provided reliable service for more than a decade.

But no matter what pump type you use, one thing seemingly forgotten in the inflation ritual (or as Larry quips, "changing the air in your tires" as butyl tubes lose so little air each day that re-inflation is more like a weekly chore than a daily one) is the need to "burp" the Presta valve (as in letting a bit of air out) BEFORE you push the chuck on. The little seal on the other end of that valve stem has been under tremendous pressure, so help your pump push it off its seat and let more air in by bleeding just a bit off before you put the chuck on and start pumping. 

We like threadless valve stems on our tubes - note they don't need a nut screwed down against the rim and neither do the ones with threads. Leave it off and while you're at it you can ditch the plastic valve cap as a Presta valve (unlike a Schrader type) can't get dirty inside - the plastic cap is there only to keep the valve from damaging the tube in the box! We think latex tubes are a waste of money as they're durable in some ways and fragile in others and we honestly can't tell any difference in ride quality vs our favorite butyl tubes. And worse, they lose air quickly, so the air pressure you start with in the morning is often not what you finish with in the afternoon.


Above: still our favorite inner tube

A push-on Presta chuck needn't be jammed all the way down on your valve stem, making removal so difficult you risk tearing the stem out of the tube. Just ease it on, if it leaks air while pumping, push on a bit more. Putting the valve stem at 6 o'clock (at the bottom) lets gravity help the chuck resist blowing off.

Your next question should be: HOW MUCH AIR PRESSURE? Larry can't count the times he's walked into the bike room and seen daylight under the feet of someone pumping their tires while the pump's rubber hose balloons outwards! Often it's just because they neglected to "burp" the valve but too often they're pumping to MUCH higher pressures than they need. Click HERE for an explanation of optimum tire pressures vs rider/bike weights, etc.

Here's an example: Let's say you and your bike weigh a combined 175 lbs. In a normal riding position 55% of that weight is on your rear wheel. A 23 mm tire needs barely more than 100 psi for optimum performance while a 25 mm tire barely needs 90 psi! We prefer 25's (or fat 23's) like the brands pictured for this reason. The front tire needs even less pressure as it supports only 45% of the weight. There is simply NO reason to use more air pressure than this!

Optimum performance means just that - reasonable rolling resistance (recent studies have debunked the "more pressure is better" mantra) plus great traction and a smooth ride. The idea is to have enough air to prevent the dreaded pinch or snakebite flat in all but the most extreme conditions, but no more. If you're the type who crashes through huge potholes rather than floats over them, this might not apply to you, but you're probably riding a tank-like machine with flat-proof tires anyway? Even on unpaved surfaces this pressure works well.

Finally, some more advice about tires. A supple, high-quality tire will improve the ride of your bike more than you would believe. Just like the sheets on your bed, more TPI (higher thread count) is better as are folding beads rather than wire beads. Don't worry so much about long wear, if you swap 'em front to rear as soon as the rear one displays a trace of flatness across the tread surface you'll get a lot of wear out of each set. Sadly, in the USA there's so much debris in the road most tires are damaged before they're worn out, but resist the temptation to "up armor" with heavy, unsupple tires that will reduce the wonderful "sing" of your bike's wheels along the pavement to a dull groan. 

If you find you can't tell the difference between high quality, high-thread-count, folding tires you can always go back to the "whatever's on sale" idea...but Larry's betting you won't!


Disclaimer: While we'd LOVE to have Michelin (Heather's fave) or Vittoria (Larry's fave) become Official Suppliers to CycleItalia, at present we supply our own tires and tubes.




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