avagadro wrote:

The rear axle, chain positioning at
istallation was incorrect.

Well, of course it is, in the platonic sense,
and the chainring/sprocket - more so the
chainring, right? - could be crooked to some
degree.

Still, should be a minor error, right

I've had this problem with professional guys
doing it, which isn't to say professional guys
cannot make mistakes. But anyway then he blamed
the new chain, and yes, I've seen this on "my"
bikes as well, onto which I always put a new
chain, so I'll not make any categoric claims at
this point...

Riding over sand with factory lube wudnot
produce slack for miles

Not even if you start and stop? N.B.
coaster brake.

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