CBR Forum - Enthusiast forums for Honda CBR Owners

CBR Forum - Enthusiast forums for Honda CBR Owners (https://cbrforum.com/forum/)
-   F4i - Main Forum (https://cbrforum.com/forum/f4i-main-forum-11/)
-   -   Trouble bleeding rear brakes... help (https://cbrforum.com/forum/f4i-main-forum-11/trouble-bleeding-rear-brakes-help-132244/)

barryf1fan 11-10-2011 01:32 PM

Trouble bleeding rear brakes... help
 
Well, I have got the ol' F4i re-wired. All new harnesses, front-main-rear, and have them working. Bike runs but now the battery needs replaced, easy enough fix.

So I'm on to just needing the brakes done with new fluid. Simple right? Wrong. The fronts are done, and good strong lever too, but the rear is fighting me. I can't seem to get the fluid to even start. I replaced the brake line from the cylinder to the caliper (one along the swingarm) and tried the same method as the front. Fill the canister with new fluid, pump the rear brake lever a few times, with the bleeder valve open, hold down the brake lever and close the bleeder. But I get no flow of fluid.

Honestly, don't know what I'm doing wrong. Anyone have some suggestions or tips on how to get the fluid to flow? Do I just need to break down and by one of the expensive bleeder kits with the squeeze pump thing (not sure what it's called)? I wish the rear would have went as smoothly as the fronts. :o

Thanks in advance,
Barry

itlnF4I 11-10-2011 01:38 PM

how many times did you do it? when you press the rear brake, a tiny amount of fluid is actually pushed into the system. the brake pads only need to move like a milimeter to touch the rotor. youll have to continue what youve been doing a bunch of times if you had an empty system

barryf1fan 11-10-2011 01:42 PM


Originally Posted by itlnF4I (Post 1112653)
how many times did you do it? when you press the rear brake, a tiny amount of fluid is actually pushed into the system. the brake pads only need to move like a milimeter to touch the rotor. youll have to continue what youve been doing a bunch of times if you had an empty system

That's what I was thinking, too. I probably did it 3-4 more times than I did the fronts... I guess the fonts being pretty much straight down, to the caliper, helps - whereas the rear is fairly straight across.

I'll try it again and see if that helps any.

I would say I did it at least 8-12 times (didn't count though) and I thought it was just clogged or something, which I did check as well.

Thanks!

Mattson 11-10-2011 01:43 PM

Walk to the nearest drug store, buy the biggest syringe they got, get it full of brake fluid, attach it to the bleeder screw with a suitable piece of tube, open the screw 1/2 turn, and force the fluid into the system "backwards". An old geezer once told me old Ducatis need to be done this way or there`s always leftover air in the cylinder.

Sick97SS 11-10-2011 02:43 PM

The normal method will get all the air out just fine on our bikes. The rear calipers and bleeders work exactly the same as the front.

Speed bleeders are nice for two man jobs like a car, but are unnecessary on most bikes where one person can reach both lever and bleeder at the same time.

Are you sure your backing the bleeder out enough?
Try removing the bleeder completely and pumping the brake pedal if all else fails. this will make a mess but will tell you if you have a clogged bleeder or otherwise.

edit:
I re-read and realized your saying your rear brake line is completely empty and wont even draw fluid from the reservior because of it's horizontal position. So disconnect the reservior from the frame and hold it as high as you can while you fill it with the bleeder OPEN while pumping the pedal and the fluid should fill the line.

barryf1fan 11-10-2011 04:05 PM

Thanks all!! definitely give it another shot, and try all those suggestions. Maybe I shouldn't give up so quickly as well.

MadHattr059 11-10-2011 05:56 PM

Good advice, so far, just wanted to add one more pearl...

Also, check that you are properly torqued on the banjo bolts for the hoses.
If you loosened the bolts at all, you need to replace the crush-rings that slip between
the bolt and the hose/bolt and hose/body assembly. The crush rings are ONE use only.
After they are torqued down once, they are pressure-hardened with no more give.
If you re-use them, they may have itsy-bitsy little air-leaks that will prevent proper
purging of the air in the system.

Good luck, Ern

Bobthebiker 11-10-2011 09:03 PM

you likely have airlock at the master. I encounter this at times, and the easiest way to resolve it is to pump the rear brake, loosen the banjo bolt a little at the master, and close it as you would a bleeder, then let go of the brake pedal. shouldnt need to do this more than once or twice, and you'll be pushing fluid easily.

74demon 11-10-2011 10:51 PM

Make sure not to pump the lever too quickly. Gotta give the fluid time to get into the master.

barryf1fan 11-11-2011 01:54 PM


Originally Posted by MadHattr059 (Post 1112711)
Good advice, so far, just wanted to add one more pearl...

Also, check that you are properly torqued on the banjo bolts for the hoses.
If you loosened the bolts at all, you need to replace the crush-rings that slip between
the bolt and the hose/bolt and hose/body assembly. The crush rings are ONE use only.
After they are torqued down once, they are pressure-hardened with no more give.
If you re-use them, they may have itsy-bitsy little air-leaks that will prevent proper
purging of the air in the system.

Good luck, Ern


Originally Posted by Bobthebiker (Post 1112752)
you likely have airlock at the master. I encounter this at times, and the easiest way to resolve it is to pump the rear brake, loosen the banjo bolt a little at the master, and close it as you would a bleeder, then let go of the brake pedal. shouldnt need to do this more than once or twice, and you'll be pushing fluid easily.


Originally Posted by 74demon (Post 1112757)
Make sure not to pump the lever too quickly. Gotta give the fluid time to get into the master.

thanks guys!! I'll be trying again this weekend, I really appreciate all the tips and responses. This forum is excellent!


All times are GMT -5. The time now is 12:28 PM.


© 2024 MH Sub I, LLC dba Internet Brands