Wednesday, June 2, 2010

A Tale of Two Tires

"It was the best of tires, and the worst of tires."

"Good tires, bad tires - you know I've had my share..."

Wow! The creative juices really seem to be flowing! ... NOT! (Sorry!)

On March 12, I installed my "summer" tires. And since I'm always searching for the most economical rubber, I tried a couple different, and new, models.

On the back, I installed a Vittoria Randonneur, with "double shielding." It's a mid-to-high priced tire, at $27 or so. (That's at the HIGH end of my purchasing history.)

On the front, I installed a Michelin Dynamic. At $13 or so, it was at the lower end of the tire price range.

The Michelin lasted 1474 miles - that's BAD! I bought 3 of 'em - I won't buy more after those 3 are used up. (Typically one front tire will last me the entire "summer season," and 3 times that many miles.)

It failed due to what appears to be "carcass failure." It deformed to the point where there's a lump that goes thump-thump-thump as I roll. That's happened to me before, occasionally, with low-end tires from Continental and Hutchinson.

Here's what it looked like, a couple miles before I retired it:

On the other hand, the Vittoria on the back is going strong. It looks like it could easily go for another 1000 miles. (On the back, my "summer" tires tend to last about 1500 miles at the low end, and about twice that many at the high end.)

Oh - I had 3 flat tires on the front, since March. I've not had a single flat on the back! That double shielding stuff seems to work!

The Vittoria could go onto my "favorites" list. Possibly my all-time favorites have been the Continental "Top Touring" model - no longer made. And I had good luck with a pair of Specialized Armadillo models... but they're pretty spendy.

(At some point, when I have the nerve, I still intend to try some of the Schwalbe Marathon tires that several readers/correspondents have spoken highly of. But I'll need to fortify myself to buy a $45 bicycle tire! Ouch!!)


db said...

I really like the Vittoria Randonneurs. I have them on both of my road bikes, and both sets have the reflective sidewall.

I was looking at my MTB commuter tires -- Panaracer Crosstowns -- the other day and was dismayed to see that new tires will be needed in the near future for that bike. I was kind of upset, until I did the math and realized that I had more than 2,000 miles on them. Not bad, but I'm going to try something else...

Bob T said...

I believe that some "higher end" tires may end up being more economical in the long-term due to their greater durability. The Schwalbe Marathon XR is probably overkill for commuting, but I've got at least 3000 miles on mine and there is still plenty of tread left. I use them in combination with Slime Super Thick tubes and have not had a flat yet.

Clancy said...

I am in the Schwalbe camp and just converted my brother. I think Schwalbe high prices come from such limited distribution.

Bikeboy said...

My new bike arrived with Schwalbe tires, but not the top-of-the-line. I like to use a slightly-narrower tire during the dry-road months, but when I took the Schwalbes off in early spring, they still looked like they had some life in 'em.

Let's assume that a $15 tire lasts 1500 miles, a $30 tire lasts 3000 miles, and a $45 tire lasts 4500 miles. ... All other things being equal, it would make sense to get the $45 tire and save the swapout(s). ... BUT - I also factor in the "road hazard gotcha" - I might ride over a big screw or nail or something that will trash a tire. (It's only happened maybe 3 times in all my years and miles.) If that happens 500 miles into a tire's life, I'd cry a lot less if it were the $15 tire. (That would be the ONLY reason for going cheap.)

Bob T said...

Bikeboy, I think that your analysis comparing price and mileage is right on the mark (for the tires must of us are likely to purchase, at least). My only question is: Will the higher end tire be less likely to get trashed than the lower end tire by the same road hazard? I once had a screw penetrate a Specialized Armadillo. It caused a flat, but the tire was still usable. When your tires were trashed was the sidewall damaged?

bob t said...

....continuing on this subject, last night I started wondering why car tires can last 50,000 miles (or more) but bike tires only 5,000 miles (or less). Why are car tires 10 times more durable? At first I thought it might be that bike tires are subject to more weight per square inch, but when I did some measurements and calculations with my car and bike I came up with about 15lbs per square inch for both. I use fairly wide bike tires, but even with thinner tires the difference in pounds per square inch does not (to me) seem to be enough to account for the much greater durability of car tires. Perhaps the answer has something to do with the economics of scale of car tire manufacturing has allowed the technology to advance much more than with bike tires, while keeping the costs from becoming too high. Any thoughts?

Bikeboy said...

Bob, I think it's a question of new tire tread thickness. A car tire probably has tread 1/2 inch deep... maybe even 3/4 inch. And when bald, there's probably still 1/4 inch or more of rubber between the road and the casing.

By contrast, even the most radical mountain-bike tire probably has tread 1/4 inch deep at the very most. And some road bike tires start off "bald"!! And with maybe 1/8 inch of total thickness, between the air in the tube and the road. That's a lot less rubber to wear down, before it wears out.

(A motorcycle falls in between. I get about 10,000 miles on a motorcycle tire. And they're more expensive than car tires!)

I'm sure the rubber compounds vary greatly from one vehicle to another, too.

Bob T said...

Thanks, Bikeboy. I never thought of tread thickness, but that probably does account for much of the difference in durability.