Change your brake fluid!

rayzzr · 01-18-2009, 06:56 PM

I got SS brake lines for Christmas, and got around to installing them today.

A bit of background: the bike is an 07 with approximately 11k miles. I have never changed the brake fluid on this particular bike.

I did not do a writeup, because there are many out there if you look. Also I didn't want someone following my advice and doing it wrong and hurting themselves.

If you choose to do this yourself, I'd collect the following before starting (in addition to your sockets/wrenches):
Roll of paper towels
Isopropyl Alcohol
old towels/rags
brake bleeder*

*Harbor Freight has a nice one, and it worked perfectly to do both the brakes on my KLR and the ZZR. Harbor Freight Tools - Quality Tools at the Lowest Prices

You can generally get it cheaper than $20, but even at that price it is worth it! Make sure you get air out of the lines, that there are no leaks, and that you clean up any spills with isopropyl alcohol pronto. Brake fluid and painted surfaces do not get along...

Take a look at the pics and see if you see the difference!

The first shot is the fluid I drained from the rear reservoir. The second is clean fluid from when I had the new line installed and was bleeding the lines.

brandon2286 · 01-19-2009, 11:52 AM

yup mine did the same thing i put new stuff in and it works great that old nasty brake fluid is awful

univurs · 01-19-2009, 12:49 PM

good advice bro, thanks

snlsmith · 01-19-2009, 12:58 PM

Replaced mine recently too. Was told by a guy at the dealer "if it looks like watered down coke (or soda/pop/cola depending on region), time to change it"

rayzzr · 01-19-2009, 01:11 PM

Mine did not look that bad in the reservoirs, so most of the gunk must have been in the lines and calipers.

PorkCereal · 01-20-2009, 11:53 AM

Im sure mine needs it. Front brakes felt squishy the other day. Its too cold in FLA right now to ride. Darn clock got my battery. But ill do the brake lines at the same time.

MotoRider · 01-20-2009, 02:36 PM

I pass this advice on to peps all the time.

I have a bleeder that is run by pneumatic air, so its a snap.

Takes less than 5min to do front and back brakes.

While I install new skins to there two wheeled ride, I inspect the fluid and offer the service to them if needed.

I get so many call back about the feel of the new tires and how well the brakes work. Makes me

.

Keep in mind the brake fluid you install makes a difference. The cheaper stuff goes bad faster, I use the Valvoline Synthetic Brake Fluid.

Its great you bring this to peoples attention. Over time.... dirty, water contaminated, brake fluid can break down a braking system by rusting components from the inside out. Takes a long time but it can happen.

RD-350Jim · 01-22-2009, 10:43 AM

Many people are having second thoughts about Syntheic (DOT 5) brake fluid. the problem seems to be it isn't a very good lubricator, plus other problems

Of course I ran it in my old RD 350 race bike, years ago.

ryanpettey · 01-23-2009, 05:52 PM

so about those write ups...where are they?

rayzzr · 01-26-2009, 12:00 AM

I have not read nor do I endorse any of them, so be your own judge but here is a link to a bunch of articles on brake maintenance.

Some tips that helped me:

Once you do the front and feel you have the lines bled, zip tie the brake lever overnight so it has pressure on it. Both brake levers should have good 'feel' and offer resistance once the lines are properly bled.

Use the Harbor Freight (or other) brake bleeder. Saves lots of time.

Don't reuse old brake fluid (as in a previously opened bottle). Moisture and contaminants can cause issues. Start with a clean, unopened bottle of fluid.

Clean up all spills pronto with a rag and isopropyl alcohol.

Use a properly calibrated torque wrench on the banjo bolts. They can snap if they have too much force, and seep brake fluid if they don't. As a general rule, don't reuse crush washers or banjo bolts.

Here is the link to the articles.

Disc Brake Maintenance w/ Pics!

kevin_stevens · 01-26-2009, 12:22 AM

Quote:

Originally Posted by RD-350Jim

Many people are having second thoughts about Syntheic (DOT 5) brake fluid. the problem seems to be it isn't a very good lubricator, plus other problems

Of course I ran it in my old RD 350 race bike, years ago.

No. DOT 5 fluid is not approved for use in most (any I know of except maybe Harley) motorcycle braking systems. DOT 5.1 is, and is compatible with DOT 3/4 fluids. They are completely different formulations, 3/4/5.1 is glycol based, 5 is silicone based.

Valvoline Syntech is a DOT 4 fluid, and is compatible with all other DOT 3/4/5.1 fluids. It is relatively inexpensive and has a high wet boiling point. I've used it for years in bikes and cars.

Brake fluid doesn't "go bad", therefore cheap brake fluid doesn't "go bad faster". It gets full of water that intrudes past the piston seals, and corrosion/contamination likewise. That's its job - to suspend all that crap so it can be flushed out periodically. Your job is to actually perform the flushing.

KeS

(PS - I think anyone who deliberately introduces air into a hydraulic braking system is nuts. The only reason to do so for a normal motorcycle owner is when changing brake lines. Other than that, keep the system full and simply flush new fluid through. It's very quick, very easy, and does the best job of keeping air out of the system. Flushing the front brakes on a sportbike requires 18 inches of clear tubing, an empty soda bottle, an 8mm wrench, and about five minutes.)