just did a brake job did front and back pads .. the fronts feel good and the bakes feel soft ... there is no brake fluid leaks just back brakes feel weaker then they were before I put new pads on ... any ideas ?
Check that brake pads are not fetching on the caliper mounting bracket. It happens quite commonly on Yamaha's when people reinstall brakes. It will make the brakes feel like they are full of air (weak and squishy).
Hey Deez, what exactly do you mean by 'fetching'? I changed front pads and have put less than 100 miles on them and they have a different response time when engaging. Its like I have to prime them before they catch. The reservoir window is about 1/2 full.
Remove the caliper and you will see what I am talking about. The brake pads go very close to the caliper mounting bracket. It actually touches it in many cases. This is the area in which the pad fetches up. Some people have had to grind or file some of the brake pad backing plate to clear the bracket. This does not happen very often, but it does happen. In most cases when the pads fetch, a simple loosening of the caliper and "adjustment" of the pad using a small screwdriver fixes the problem.
Now this is in most cases. I have also seen (and have personal experience with it) weak brakes when using cheap brake pads. Many cheap brake pads simply do not have enough stopping power or feel of good brake pads. This is pretty prevalent of the cheap, no name china made, ebay brake pads.