I'm having issues with my rear brake. The brake caliper is a Tektro (unsure of model) which came standard on my 2008 Specialized Allez. The brake cables are relatively new (less than 1 year old), and in good condition. The brake cable housing at the rear (where the cable enters the caliper) is several years old.
The problem is the caliper doesn't fully open after I release the brake lever. The brake partly releases, but not completely, such that one pad slightly rubs the rim. If I tap the caliper or help the cable move within the housing, the brake will fully release.
Yesterday,I removed the caliper and gave it a good cleaning. I also pulled the cable out of the housing and gave it a good cleaning and inspection. The cable is in new condition.
After re-installing, I still have the problem where the brake slightly "stick" without fully releasing. It appears there's friction in the brake housing just before the caliper, or the spring has lost its springyness and can't overcome the friction in the housing.
Is it plausible that the caliper spring is getting worn out, thereby necessitating a new caliper? Or should I just change that rear brake cable housing? I'm wondering if using a longer housing (and hence smoother bends) will help alleviate this issue.
Your input is greatly appreciated.