Brake Bleeding Tips Feb 16, 2010 13:35:23 GMT -5
Post by 90GTVert on Feb 16, 2010 13:35:23 GMT -5
Fox said:Today I had to replace a brake line on a 150cc 4 stroke. (1st time bleeding a scooter brake for me) The brake line replacement was easy but when I went to fill and bleed the system I squeezed the lever and opened/closed the bleed valve a hundred times and the fluid level in the reservoir never dropped so I was getting frustrated. I decided to remove the lever and push the plunger with my finger which made the plunger push in farther and that worked to get the fluid moving but it's hard on your finger so after staring at it for a few minutes it hit me: The lever was hitting the handle bar limiting the plunger travel!
So I put the lever back on and then I slid the entire handle assy out to toward the end of the handle bar so the brake lever was hanging out in space and tried it. Voila! The lever wasn't limited in it's travel by the handle bar and the brake was bled in less than 5 minutes!
Hope this helps somebody.
stepthrutuner said:I was bleeding my Derbi brakes the other day and encountered a similar problem. Whatever works best for each individual situation is appropriate. What worked for me was making very, very small strokes (1/8 to 1/4 inch at the end of the the lever ball) to get the fluid moving while leaving the caliper bleed fitting open. I just kept making those tiny strokes until no more bubbles came out (of the reservoir). In the past I have taken things apart as you did. This time I avoided that.
Now when I first started bleeding brakes by myself, I would fill master cylinder, put on lid to master cylinder and pump brake lever, put bungy cord around lever and handle grip, bleed open line to let air out, close line, pump brake 3 times, put bungy cord on lever and handle bar grip, ect.. repeating, and repeating. Every third time in the procedure, I would take off master cylinder lid and add a little brake fluid. Put lid back on and repeat. It gave me a lot of braking power, but this method ruins the screws if taking off and on. I bought new screws at the local hardware store. They have small metal screws that are metric.