Adding brake fluid to master cylinders

[Constant Mesh]

When changing/adding fluid in the clutch and brake systems what is the best way to transfer the new fluid from the can or bottle to the master cylinder reservoir? Use a small funnel, etc.? I'm concerned if I try to pour the fluid directly from the can to the reservoir I'll spill a few drops on a painted surface. Changing the fluid will require more than one pour -- more chances for a spill. The rear brake reservoir is not as accessible as those on the handlebar.

 

[radman]

When changing/adding fluid in the clutch and brake systems what is the best way to transfer the new fluid from the can or bottle to the master cylinder reservoir? Use a small funnel, etc.? I'm concerned if I try to pour the fluid directly from the can to the reservoir I'll spill a few drops on a painted surface. Changing the fluid will require more than one pour -- more chances for a spill. The rear brake reservoir is not as accessible as those on the handlebar.

I put an old towel on the fairing when servicing the bar mounted masters, and unbolt the rear res (one screw) when filling the rear.

 

[quicksilver]

Ooo, good idea on the rear.

I'll trying that on the next service.

 

[zzkenoman]

Another way to protect your tank is to use "puppy pads", with the plastic on one side and the white absorbent material on the other side. The towels are only good if you remember to change it if any brake fluid drops on it, otherwise it soaks right thru and destroys your paint (don't ask me why). Otherwise, have a good friend help you pour the fluid with a small plastic measuring cup.

 

[Colin24]

When I'm bleeding brakes/clutch I remove all the bodywork from the area around (and below) the master cylinder being filled. Brake fluid is just too nasty to risk it getting on bodywork (plastic or painted). For the clutch/front brake I remove the tank and fairing and have them well out of the way. Then I pack a clean rag around the master cylinder to catch any drool that might come down the sides.

Be careful when you pump the lever to get the new fluid through the system. If the cover is not back on the master cylinder it can spit back out when you let go. So I always try to remember to put the cover back on (even loosely) to stop the fluid from squirting onto the bike when I am doing the actual bleeding.

Finally I keep a can of aerosol brake degreaser and a roll of paper towels handy so if I do get a drop of the brake fluid on something I can get it cleaned up immediately.

Hope this helps

Colin

 

[Groo]

... and unbolt the rear res (one screw) when filling the rear.

+1

This reminded me that I went and replaced the Phillips head POS screw that attached my rear reservoir when I was installing the Spiegler lines for something with a hex head, that I could actually get to without worrying about rounding it off (which the original POS showed a propensity for doing).

 

[trimmantom]

If you are just bleeding the old fluid out try useing a mightyvac.

It makes bleeding so easy and you don't have to worry about brake fluid poping out of the master cylinders.

Just pop off the covers connect the hoses,pump the mightyvac a half dozen times and open your bleeders and the flow will start the suction out of the old nasty stuff.It will suck out pretty quick so you have to keep the resevoir full of new fluid. After I used a mightyvac a couple of times it made that bleeding process very easy with no pumping of the levers.If your so inclined to do a bleeding procedure try this tool it is worth the money to simplify this process.I just throw a couple towels on the areas under the resevoirs to keep the nasty **** off the painted surfaces.Also you might want to tie down your handle bar and make it immobile so as not to have an accidental twist of your bars and areal friggin mess. Good luck

 

[ONE MORE BIKE]

Evacuate the old fluid from the reservior and refill with clean fluid prior to starting the exchange process.

Remember to flush area with clean water when done.

 

[Constant Mesh]

The local AutoZone has a vacuum pump kit for $29.95 including:

PVC MityVac vacuum/pressure pump with vacuum pressure gauge

Fluid transfer bottle with transfer and storage lids

Misc. hoses and adapters

Is this an adequate kit for an FJR home mechanic?

 

[radman]

The local AutoZone has a vacuum pump kit for $29.95 including:
PVC MityVac vacuum/pressure pump with vacuum pressure gauge

Fluid transfer bottle with transfer and storage lids

Misc. hoses and adapters

Is this an adequate kit for an FJR home mechanic?

It's what I use. And use. And use.

 

[Mike-H]

I concur with Rad...had mine 6 years & won't be without it....

 

[madmike2]

Yep. They last and last and last and.........

 

[trimmantom]

That is the same pump I have.

It will serve you well.When you use it, it is not necessary to run the resevoir dry.

This will just put air in your lines.

Keep the resevoir topped off and suction fluid through til it's clear.

The only time you need to drain the system is when you're replacing the lines.

Also remember to use the correct type of brake fluid.DOT 4.

The clutch resevoir holds less fluid then the brake resevoir also, so if you do that line you'll have to add fluid there a little quicker or you'll run it dry. Have fun.

 

[bikerjazz]

When changing/adding fluid in the clutch and brake systems what is the best way to transfer the new fluid from the can or bottle to the master cylinder reservoir? Use a small funnel, etc.? I'm concerned if I try to pour the fluid directly from the can to the reservoir I'll spill a few drops on a painted surface. Changing the fluid will require more than one pour -- more chances for a spill. The rear brake reservoir is not as accessible as those on the handlebar.

I pour my brake fluid (Valvoline SynPower) into an old BMW DOT 4 bottle. This bottle has a long skinny neck that makes pouring the brake fluid easy. Like the Rad, I also throw an old towel over the bodywork below the reservoir. To get an even fill, I turn the handle bars to get the reservoir as level as possible. I then loosen the reservoir clamp and temporary turn it to get it even more level.

 

[ionbeam]

+1 on removing the rear brake reservoir. The lid on my reservoir was really tight and that was the only way I could get a good grip on it. Using pliers or equivalent on plastic didn't seem to be a good idea.

My first plastic MityVac only lasted ~25 years. I replaced it with a brass model that I will probably leave to someone in my will. I fabed my own fluid transfer bottle to get extra volume.

Now to see if Lorie burns her boots on the cans. Might try to fabricate some guards - jestal has motivated me!

[SIZE=12pt]'06 Warning -- > these heat shields are not for you![/SIZE]

Bike Johnny

Pillion Exhaust Shield for Extended foot rests. YA10-09-006-52

 

[ionbeam]

The shields are pricy, arrived quicker than most USA part orders and fit well. I didn't like the appearance as shipped so I had mine powder coated. After 18k miles they are Pillion Approved.

 

[tyronewildman]

Mity Vac for me. When useing the Mitey Vac it will draw in air thru the threads of the bleed valve & will show up as bubbles in the vac hose so you are not sure if there is air in the brake lines or not. Before loosening the bleed valve, I coat all around the bleed valve threads with a "Tinkers Dam" of light grease so it won't draw in outside air. This way you can see when you have removed all the air in the line. Note-I really use Vasoline for the light grease but hesitate to say that cause because of all the funny responses I know I'll get. Later,,, De

 

[jestal]

I just had to read this thread seeing 19 replies about adding brake fluid....????..... Put a rag under the master cylinder, add the fluid and get on with life. This is not a difficult task. Brake fluid will take paint off, yes, but NOT in seconds. If you spill, wipe it off and clean the surface. It is not like the Alien's acid snot that would eat thru the steel deck instantly. LOL.

 

[radman]

I just had to read this thread seeing 19 replies about adding brake fluid....????..... Put a rag under the master :dribble: cylinder, add the fluid and get on with life. This is not a difficult task. Brake fluid will take paint off, yes, but NOT in seconds. If you spill, wipe it off and clean the surface. It is not like the Alien's acid snot that would eat thru the steel deck instantly. LOL.

Wrong, engineer breath. Spilled brake fluid is a primal fear, cave drawings show mastodons dissolving in large pools of brake fluid in what is now Central LA. Modern engineers (real ones) have linked spilled fluid to a valve guide problem in a modern motorcycle, the name of which escapes me at the moment. :dribble: