Originally Posted by
cyccommute
Yes, the cracking is due to incorrect spoke tension but not necessarily “incorrect” in the way that most people think. Cracks can form from both low and high tension. Low tension allows the spoke bed to flex constantly which leads to cracking. High tension stresses the aluminum of the rim and leads to cracking. Two different mechanisms but the same result.
I had the same issue and only found it after breaking a spoke.
Low tension usually results in broken spokes - there are sometimes multitudes of broken spokes from a particular manufacturer's bikes from a single production year. These are sometimes blamed on a 'bad batch of spokes', but I believe it is usually a badly tensioned batch of wheels. As CC said, the same mechanism ('fatigue' as the wheel rotates and spokes move from minimum to maximum tension and back again) can cause cracks in the rim.
As for Specialized Warranty - as a vendor of mass manufactured items made by contract manufacturers, when there is a warranty issue it often involves thousands of bikes. A few years ago they were having problems with the freehub bodies on Specialized branded hubs. If you were one of the first few hundred to report the problem then you were sent a new freehub body in short order, but if yours failed later in the season, the NA distributors had no replacement parts left and you had to wait, unless your shop was kind enough to do some type of swap with non-Specialized-branded parts. This problem happens occasionally as companies try to cut the pennies they spend on parts they order from external vendors to maximise profits.
It seems that a lot of bike companies don't actually expect their bikes to be ridden, and this attitude often pays off... say Manufacturer X saves $5 on each bike it equips with a certain cost-cutting part, but that part is expected to have a 20% failure rate. Manufacturer X sells 200,000 bikes per year with that part, so this decision saved them $1,000,000 during production. Manufacturer X knows that 50% of its bikes are only ridden a couple of times before being moved to the back of the garage as a dust collector, so they only expect 10% of those cheap parts to come back. They probably also expect not all people will realize that they can get a free replacement under warranty, or will otherwise chose to fix the part on their own - maybe another 50%. So of the 40,000 potential defective parts they need to replace, they expect to be held responsible for about 5,000. This is all worked into the initial cost of the bike. In the OP's case, they probably got wheels from a vendor who delivered at a substantial discount, but they underestimated the number of failures and are having a hard time keeping up.