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Rear brake basically sucks

  #1  
Old 03-17-2011, 06:10 PM
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Default Rear brake basically sucks

Dont get me wrong guys, i know the rear brake is practically useless and 90% of braking comes from the front brakes.. that being said im curious what your experiences are.

I just put new pads on my front and rear and bled some nice new dot 4 liquid into the caliper ( ended up needing to re-tap one of the bolt holes on the rear caliper after it cross threaded... DOH! )

Took the bike out for a ride and i can feel a difference in the front brakes, they are not even worn in yet and they are grabbing real nice.. now the rear brake feels practically useless. I just about have to stomp on it while coming up to a light to slow down.


Anyone have a similar experience or do i need to take the caliper / master cylinder apart and clean them? Could the disc have "glaze" on it?
 
  #2  
Old 03-17-2011, 06:16 PM
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I just got my F4i a couple weeks ago and I noticed the same thing. Not sure if it is just these bikes or not, but I would definitly like to get more rear brake out of it.
 
  #3  
Old 03-17-2011, 06:21 PM
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+1

Same **** here. I was recently working on my bike, and after a test ride i came back and was like "****, my rear brake sucks." Oh well. Let me know if you guys figure something out.
 
  #4  
Old 03-17-2011, 06:47 PM
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Either its normal. (if its the same as before) or its still got air in it from the sounds of it. (if It's comparatively worse than before.

That's my best guess without feeling it.
 
  #5  
Old 03-17-2011, 06:55 PM
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if the rear brake caliper bolts are not perfectly centered like they should be stock, the rear brake will not work properly..
i ran into this myself...
i replaced my rear tire put it all back together and noticed that the rear brake wasn't working like it did before.. i took the caliper bolts out and noticed that the front bolt threads looked like they had been striped.. i got the bolt back in straiter than it was but still didn't feel right.. i did everything i could think of, heat up the pads by holding the brake wile riding, resurfaced the rotor, bleed the the system twice, it got a little better but same thing...

look at your rear caliper when you push the brake pedal, if it moves strait there is another problem, but if it ***** to the side just a little the caliper is not centered and it can't grip the rotor evenly, hence spongy little to no stopping power....

before you buy a brake caliper bracket off ebay make them send you a pic of the threads.. if they want to sell it they will, if not keep looking you might not want it...
 
  #6  
Old 03-17-2011, 07:17 PM
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The rear brake is only a single piston so there is way less power than the front,
and if your rolling in gear it will be hard to slow because you will kill the engine.
Try pulling in the clutch and see if you can lock the rear should be able to if not
you have some kind of issue with the brake.
 
  #7  
Old 03-17-2011, 07:18 PM
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Originally Posted by crazychris1981 View Post
if the rear brake caliper bolts are not perfectly centered like they should be stock, the rear brake will not work properly..
i ran into this myself...
i replaced my rear tire put it all back together and noticed that the rear brake wasn't working like it did before.. i took the caliper bolts out and noticed that the front bolt threads looked like they had been striped.. i got the bolt back in straiter than it was but still didn't feel right.. i did everything i could think of, heat up the pads by holding the brake wile riding, resurfaced the rotor, bleed the the system twice, it got a little better but same thing...

look at your rear caliper when you push the brake pedal, if it moves strait there is another problem, but if it ***** to the side just a little the caliper is not centered and it can't grip the rotor evenly, hence spongy little to no stopping power....

before you buy a brake caliper bracket off ebay make them send you a pic of the threads.. if they want to sell it they will, if not keep looking you might not want it...
Just checked mine and had my family double check, my caliper does not move while the brake is pushed, the disc does have very slight grooves in it from the PO not replacing the pads on time though.. think it will just take a while to seat to the disc?
 
  #8  
Old 03-17-2011, 07:22 PM
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Yeah, rear brake is just a tiny single piston caliper. Nothing spectacular about it. Just make sure it's straight and your line is free of air and it should be fine. You should be able to lock your wheel up, but don't expect it to slow your bike down dramatically by itself.
 
  #9  
Old 03-17-2011, 07:43 PM
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i might be wrong but i know for a fact that when i swapped out the swing arm to the rr with the rr caliper bracket i did not have that problem any more...


Survivalism sounds like you need to either replace or resurface that rotor..there is also the chance that it is warped..take out the bolt and look at the threads on the caliper bracket...

true it is only one piston but when working like it should with GOOD pads it will slow the bike down slowly, until you press hard on the pedal to lock it up..

.i know i am stupid for doing it but getting off the highway i will clutchless down shift and hold pressure on the rear brake wile sitting upright on the seat not holding on to the bars.. not real smart but it looks cool...lol....again not smart so don't do it unless your a little crazy like me...
 

Last edited by crazychris1981; 03-17-2011 at 07:47 PM.
  #10  
Old 03-18-2011, 09:42 AM
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Rear brakes on f4i's suck from the factory. Mine has always been the same [still original pads] for 46,000 miles now, and that includes two fluid flushes. They do work, they just require more pedal effort then any other bike I've ridden. I consider it a good thing because when you put boots on its really easy to push down too hard and lock the rear while setting up for a corner.
 
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