I have a 2009 CBR1000RR non-ABS type.

In my almighty wisdom (or lack thereof), I decided to change my fluids. Did the oil/filter. The maintenance schedule (I actually have the Honda service manual) also suggests changing the coolant and brake fluids every two years. Coolant is all done and fine. However my brakes are not coming together. Here is my situation:

I changed the rear brake system using Prestone synthetic DOT4 brake fluid. Bled it appropriately and it works fine. Did the same for the front brake system. Followed the steps appropriately: Drained old fluid, added new fluid, systematically bled each caliper, added fluid to the reservoir, etc. There are no air bubbles coming out of either front caliper. Should be done, no? Well the front brake lever still feels soft/spongy. Did the whole process twice, no success. Took it out for a low-speed spin around my block, despite the spongy lever. Back brake indeed works fine. When I pull the front lever, it seems to stop the bike SOMEWHAT reasonably. Definitely takes slightly longer distance than before I changed the fluid. I even went up to 35 MPH. Also, the lever squeezes right to the grip, without too too much resistance.

Now, I have adjustable levers (I don't remember who makes them) which have settings 1-6. Setting 1 is short travel (close to the grip at rest) and 6 is long travel (far from the grip at rest). I have always had it on setting 4, and it worked fine. The brake did occasionally drag ever so slightly, though. If I put the lever on setting 6 now, it's closer to what it used to be when I had it on setting 4.

My brake pads aren't exactly new, but nowhere need replacing. They worked fine when I pulled it into the garage before I started this project. The Honda service manual lists the following possibilities:

-air in hydraulic system
-leaking hydraulic system
-contaminated brake pad/disc
-worn caliper piston seal
-worn master cylinder piston cups
-worn brake pad/disc
-contaminated caliper
-clogged fluid passage
-warped/deformed brake disc
-sticking/worn caliper piston
-sticking/worn master cylinder piston
-contaminated master cylinder
-bent brake lever

I feel like I can rule most of these out, given that A) it worked fine before I started, B) fluid flows out of the bleed valves fine, and C) no air flows out.

Help? Thanks!!

 

Have you tried pushing fluid back up through the calipers?

 

Most likely, you still have air in the lines. I am assuming you only drained and
replaced the fluid, you didn't mess with the banjo-bolts or anything else.

If so, none of the rest apply, if you weren't experiencing any symptoms before.

Demon's suggestion is one alternative, but it's best done at the onset of the fluid
replacement (less messy). You can still use that method, just draw off the fluid in
the MC first to leave room for the fluid you are adding.
Do a search for some tips/tools for this method.

A vacume pump with a fluid resoivour, between it and the caliper, is another alternative.
Again a search will provide lots of idea/tips.

I'll elaborate on the standard method, to be sure you are performing it properly...

Correct procedure is to pump the lever several times, then on a final squeeze-hold the
lever down and ease the bleeder nipple on the caliper to draw off the bubbles.
Don't let the lever go all of the way in before re-closing the nipple.

The hose attached to the nipple should arch up and then down into a reserve of fluid.
Be sure the end of the hose stays below the surface in the catch-basin. All of that,
assures that you don't draw air back into the system. This should all be done with
the cap and diaphram removed from the MC. With this "top-down" approach,
be sure the MC DOESN'T run empty (or you'll draw more air into the lines).

With the tiny, micro-bubbles that are common, it helps to go back a couple of times.
Leaving it over-night for the bubbles to percholate up and out of the lines.
And then re-bleed. Do this till you are satisfied with the results.

DO NOT ride a bike with a known brake issue. Murphy's Law will see that you regret
the decision. Dogs, cats, gravel and cars will suddenly appear before you, where
previously, it was never an issue.

Good luck, ride safe, Ern

 

It looks its all been covered, and seems like you still have air in the system as already suggested. The only thing I might add to the procedure is using a small wooden dowel or handle of a hammer. Air can become lodged in the system. Each time you pump the lever and build the pressure up to bleed, tap the reservior, calipers, lines and y joint. This will help dislodge any air that may be trapped and help it move towards the bleeder or reservior. You are moving a very small portion of fluid and sometimes, there is not enough flow to move the air out of the system, and it just keeps going back and forth. Air bubbles can actually stick in place and require some assistance to move.

Also, if drastic measures are needed. In the past, I had to remove the calipers from the bike and raise them up as high as possible. The new angle and height allowed the air to move upwards towards the bleeder on its own and I could bleed them this way. Keep in mind if you do this, you will need a piece of material to simulate the rotor between the brake pads. I've only had to do this one time, but it worked when nothing else would.

 

I like this bc pushing definitely gets the air out

 

Another tip that sometimes works is to tie the brake lever against the throttle and let it sit overnight. Air can and will then percolate up to the MC and be released.