Untrue Wheels

[Portellini]

Dear members,

I need your help in order to understand something. I have a 2007 Specialized Globe Sport. I bought it second handed and it was almost new when it came to my hands, about 6 months ago.

It came with Alexrims wheels and since I bought my first 700x23 tires, and the back wheel keeps untruing even though I had them trued @ the bike shop for more than 3 times for the last 4 months. Thinking that 700x23 tires because of the high pressure they require were the responsible for the untruing of the wheels, I put my 700x35 wheels back.
Now I am using some excellent, puncture free, Schwalbe Marathon 700x28 that require a bit more pressure than the previous 700x35 ones. And today i sensed something strange on my ride. I went to check and a part of the rim was rubbing my break pad again.

Is this a problem of mine or the rims? Maybe I ride from some sidewalks to roads and vice-versa and the wheel suffers some additional impact. I don't know. Can you help me?

Thanks a lot.

Pedro

[nfmisso]

Pedro;

The spokes have not been properly tensioned, trued and stress relieved.

The correct process is:
* tension
* true
* stress relieve
* true
* repeat last two steps, until truing is no longer needed; usually three or four repeats.

make sure the tension is sufficient.

if there is any failure after this, either the hub or rim is cracked.