F4i - Main Forum Main F4i discussion board

Front brake inconsistent feel

  #1  
Old 02-06-2018, 07:52 PM
Junior Member
Thread Starter
Join Date: Sep 2015
Location: TX
Posts: 2
Default Front brake inconsistent feel

2006 F4i, ~9000 miles, front brake seems to not always be consistent in terms of how much I need to pull it in to get equal braking action, if I haven't used it in a while (15 minutes?) the lever gets a little bit soft, although it'll still brake hard enough to lock the front wheel. Bled the brakes at the caliper and also by ziptie'ing the lever overnight. Stock rubber lines, but the look to be in good shape, don't see any leaks in the system and it doesn't lose fluid.

I'm thinking either faulty master or warped rotor maybe?

Unrelated - if anyone has a yellow tailing fairing and/or a 06 yellow/gray left side fairing they're selling, shoot me a PM.
 
  #2  
Old 02-06-2018, 08:03 PM
Senior Member
Join Date: Nov 2016
Location: Dorset
Posts: 200
Default

It could be the master cylinder spring needing replacement. Think warped rotors would mean brake judder?
 
  #3  
Old 02-07-2018, 01:08 PM
Senior Member
Join Date: Jul 2008
Location: Mesa AZ
Posts: 1,998
Default

Zip tieing the lever overnight? Sounds like a good way to not bleed them correctly...
 
  #4  
Old 02-08-2018, 06:14 AM
wes 17's Avatar
Senior Member
Join Date: Sep 2012
Location: wales
Posts: 333
Default

Sounds like confidence in that front brake is missing and from your description I’d go for disc issue.
Time to give the brake a good overhaul and get you pulling stoppies, not stopping like your pulling up to the grid on your MotoGP bike.
Warped disc can be checked by lifting the front end and fixing a marker pen to your fork leg, just off the disc, and give the wheel a spin. The pen needs to be v close initially but if it’s out you’ll see it marked on the disc. Prove this by further spins after cleaning. There is a tolerance for “run out” but this is marginal and a true warp is clear. This method does work but be patient setting it up.
Get those calipers off and give the mechanisms a going over and clean them up. Force the pistons out and clean and double check everything. No point in putting it back together with any compromise anywhere. Check pad sliding pins for free movement ( an issue I’ve had ) .
If your brake lines all good, now time for good bleed.
Best of luck mate.
 
  #5  
Old 02-08-2018, 06:24 AM
wes 17's Avatar
Senior Member
Join Date: Sep 2012
Location: wales
Posts: 333
Default

Originally Posted by ceebeeaarguy View Post
It could be the master cylinder spring needing replacement. Think warped rotors would mean brake judder?
Makes an elegant gliding up to a stop rather difficult.....more like someone’s mate who’s borrowed it lol
 
  #6  
Old 02-14-2018, 05:52 PM
Senior Member
Join Date: Jul 2008
Location: Mesa AZ
Posts: 1,998
Default

Either the rotor is warped enough to push the pistons back in, requiring the pump to push them back into contact with the rotor, or your master cylinder is going bad.
 
  #7  
Old 02-16-2018, 12:26 AM
Junior Member
Join Date: Mar 2013
Location: central NJ
Posts: 23
Default

wouldn't warped rotors cause a judder or even a twitch (feedback) into the lever from movement?
I would suggest getting some fresh brake fluid in the res. and doing a thorough bleeding with some clear tubing so you can be certain that the fluid is bubble free.
 
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Brookhouse16
F4i - Main Forum
16
08-25-2014 02:14 PM
mnguyen84
F4i - Main Forum
8
02-20-2013 10:41 AM
DarkNinja75
CBR 600F3
0
10-15-2008 05:22 PM
king4beer
CBR 600F3
5
07-08-2007 06:32 AM
redliner25
Stunters Corner
13
08-22-2006 09:10 PM


Thread Tools
Search this Thread
Quick Reply: Front brake inconsistent feel


Advertising
Featured Sponsors
Vendor Directory

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.