How interesting.

After two lbs's told me I had as good a chainline as one could expect, I put my Pista up in the garage workstand and gave it a long and serious eyeballing.

As I eyeballed the sprocket, I noticed it had a flange around the hole for the hub, but only on one side and not on the other.
I speculated that flipping the sprocket over would move the sprocket over, about an eighth of an inch closer to the centerline of my bike, and thus give me a perfect chainline.

So, I rode down to the lbs that sold me my Pista, and which also assembled the bike for delivery.
Why, yes, they had put the sprocket on backwards.
With a little encouragement from me, they flipped the sprocket over and I now have a perfect (I mean perfect) chainline.

I need to invest in a lock ring wrench and a chain whip so that I don't need other people to keep my bike rolling.
I should start a thread asking for a minimum tool and parts list to keep my Pista (and me) happy.

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Anyway, during the eyeballing phase, I noticed my Armadillos have an arrow on them and the words "direction of rotation."
If I put a sprocket on the other side of the hub, so that I could change sprockets by flipping the wheel, that would change the direction of rotation.
Does this matter, or, did the Specialized folks just put the arrow and the words on the tire to make it look more "specialized"?

good work.. just be careful.. sounds like youre getting dangereously close to being that "oh no hes back again" dude to your lbs... you dont want to be that guy

Well this was a fair return to the store, they improperly installed the cog, it is their responsibility to correct it.

I have often wondered about the direction thing too. I have always mounted tires according to the arrow. But really, whats gonna happen if you dont?

When you pedal forwards, the bike will go backwards!!! And the world will slowly start to spin backwards, reversing time!!! All sorts of crazy things will happen! Don't do it!

so if go fast enough, i can reverse time and eventually i will have gone back enough that the direction of my tire will switch to the correct position. Then i will be stuck in a paradox.

i know it was a fair return.. but if youve read his posts.. our man ken, who we love to death, has spent many a day waxing unpoetic about chainline issues at the greater Bend lbs' ... i worked in a bike shop all through jr high and high school.. i have a good feeling for this kinda thing..

How did the LBS miss the fact that they put the sprocket on backwards???

Oh, Ostro, 99.999111% of flat tires are caused by people putting their tires on with the arrows pointing in the wrong direction.

You'll also go 3x faster if the arrows point forward. This has been wind-tunnel tested!!!

Whats the correlation?

Arrows pointing backward cause wind drag!

just as long as we don't get "stuck in a paradox". Those things are so hard to get off, especially when they're wet....

At Area 51 in the Nevada Desert, they have an alien fixed gear bike with NO chainline, arrows that don't point in any direction and it's made from material that's lighter than Carbon Fiber!

many car tires are strictly unidirectional

i've had road bike tires that are unidirectional as well. however, its my personal opinion that that doesnt mean much.

larger, knobby mtb tires have angled knobs designed to shed mud or to grip in loosely-packed surfaces.... with those i'll adhere to the mounting directions.

with skinny road tires? nah. hell, an ideal tire would be bald and have no specific direction of optimum grip/performance

Coming off on that, are there any tires out there that have zero tread on it?

so true. so true.

of course.

https://www.specialized.com/SBCEqProd...dv8f0au.j27003

There definately are, but can only be ridden in states that have "dont tread on me" mottos