F4i - Main Forum Main F4i discussion board

rear brake fluid reservoir

Old 07-24-2011, 06:39 PM
tyfrist's Avatar
Thread Starter
Join Date: May 2010
Location: Btown INDY
Posts: 67
Default rear brake fluid reservoir

well i was at my grandparents the other day and my grandpa looks at my bike and goes is that a brake fluid reservoir? I said yeah that's just for the rear brake.

he goes, well there is no fluid in there!?!?! hahah well turns out there it was empty and it makes sense because when i was changing the sprockets i couldn't get my rear brake to stop and hold the wheel to tighten some of the bolts.

I haven't found a leak yet, but i did notice a silverish type fluid/stain on the right side of my bike underneath the reservoir, but i don't think brake fluid is silver? i just used a heavy duty engine degreaser and spray it all over the rear of the bike so i'm assuming the silver stuff is from that but i don't know where the rear brake leaked from.

And once i put it more fluid i'm going to need to bleed them right?
Old 07-24-2011, 08:42 PM
Kuroshio's Avatar
Senior Member
Join Date: Jul 2009
Location: West Philly, PA!
Posts: 4,476

If there's no fluid, the entire rear brake system is full of air. Including the master cylinder. If you don't have one, I recommend getting a vacuum pump from the local auto parts store to help. It'll be difficult to bleed it without one.
Old 07-25-2011, 01:10 AM
Senior Member
Join Date: Jul 2008
Location: Mesa AZ
Posts: 2,024

Fill it up, bleed it, then watch for leaks.
Old 07-25-2011, 02:47 AM
DonnyBrago's Avatar
Senior Member
Join Date: Aug 2009
Location: UK
Posts: 377

The rear brake is easy to bleed, just need a clear tube over the bleed nipples and into an empty bottle and some brake fluid. The hard part, or rather the part people fail miserably at is getting the initial lever pressure, once the MC is pushing fluid it is easy, if you don't bleed the MC first then you are just squashing air inside the MC.

Fill up the res and do not let it go empty at any point. Best to start by bleeding it at the MC banjo first to get the MC pumping fluid, i.e. crack the banjo open and pump the lever a few times to get some pressure and fluid movement (use a rag to mop up spills), then tighten it up and bleed it at the caliper (pump, crack open the nipple for a split second then retighten - repeat). Do it at the caliper until the clear plastic line is not pumping out any bubbles. If the lever is still soft then bleed at the MC banjo again, and bleed at the caliper banjo before doing a few bleeds at the nipple.

Sounds tricky but it is not, you'll quickly get the feel for it.
Related Topics
Thread Starter
Last Post
F4i - Main Forum
05-07-2011 04:40 AM
F4i - Main Forum
11-03-2010 08:46 PM
F4i - Main Forum
04-01-2008 04:10 PM
General Tech
07-21-2006 01:07 AM

Thread Tools
Search this Thread
Quick Reply: rear brake fluid reservoir

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.