Hello, John Talley here with Partzilla.com.
Today I'm going to show you how to bleed the brakes on our 2009 Yamaha YFZ450R.
Really simple to do.
Let me go grab a couple of tools and we'll go right through it.
Listen, this is only going to be a skill level one.
It's going to be really simple, and I can prove that by the fact we only need a couple
of tools to pull this off.
Which tools?
Well, a Phillips screwdriver, an 8mm wrench, some type of container, and then a length
of quarter inch hose.
Now, as far as the parts go, there's only one.
All you need is some DOT4 brake fluid.
Me?
I prefer to use whatever the OEM manufacturer put in the machine when it was brand new.
So, once you've got your tools and your DOT4 oil ready, we can jump over there and I can
show you how to do it.
Alright I'm going to go ahead and lift this one up and get the front tires off, but that's
not absolutely necessary.
You can actually bleed it with it sitting on the ground.
I'm just taking it off so you'll be able to see what I'm doing.
Alright, let's start by taking off the cover on the reservoir on the master cylinder for
the front.
Just a couple of Phillips and if they don't break loose immediately using just a regular
Phillips screwdriver, you may want to use an impact Phillips.
Take off the cover, clean up this plastic section.
then there's a little rubber diaphragm that needs to come out.
Yep, looking like Coca-Cola in there, so it's definitely time for a flush.
The name of the game here is clean, because you don't want to introduce any contaminants
into the system, whether it be dirt, water, or whatever.
Alright, so we've got our reservoir opened up and all we have to do now is connect a
length of hose to the bleed valve right here and then that needs to go into some type of
container.
I just drilled a hole in the top of a regular quart of oil that we had already used.
So, here's the process.
Pump this up, hold, open the valve til it bottoms out, then close the valve and repeat.
I typically do this pretty much every time I go through a brake pad change, so that's
when it needs to happen.
That or annually.
Because brake fluid is what they call hygroscopic, and it attracts water into the system and
that's what we don't want to stay in there.
Plus, the fluid that down at your caliper, well, it's pretty much staying there the whole
time and every time it goes through a heat cycle, that starts to break it down a little
bit, so it's important that you get quote-quote new fluid down into the caliper area.
As you're doing this, you need to keep an eye on your reservoir because what you don't
want to have happen right now is to introduce air into it, because I know this system is
working like it's supposed to so I don't want to have to start over by forcing an air bubble
all the way down and through the caliper.
I'll do this in between 20 and 25 times, checking along the way to make sure I still have enough
fluid.
Alright we're getting a little bit close, so I'm going to fill it back up and keep going.
Do this side a few more times and then we'll head over to the left and then do it.
Alright, we're going to go ahead and fill this back up and go switch over to the left
side.
Tighten up.
Same procedure as the right side.
Let's go take a peek at that reservoir again and see where we are.
Yep.
Alright guys, that should do it.
Only thing we need to do now is set our level.
Tighten than back down all the way, then don't forget to put your dust and dirt cap back
on.
Alright, we are going to refill it to about right here, just below that upper section
of the sight window.
alright, there's one thing I want to caution you on when you go to refill and set the level
on the reservoir.
If you have old brake pads and you fill it all the way to the top and you put new brake
pads on it later, well guess what?
That fluid is not going to have anywhere to go.
So, if your pads are worn out, don't take it all the way to the upper level.
I know that we just replaced the brake pads on this machine not long ago, so, I'm good
to go up to that upper mark.
So let's get it filled up.
That'll do.
Now at this point we can co ahead and put the diaphragm back in along with that plastic
spacer, and then the cover itself.
Alright, with the front finished up, let's move around to the back and get it taken care
of.
Alright, we've got our dust cap out of the way, let's go and connect up our quarter inch
hose.
And the rear reservoir is actually up under the seat.
And that is it right here.
Put together about the same way.
Nylon spacer, rubber diaphragm, and then just the cap.
Alright, we've got it opened up, I'm going to go ahead and top it off and we'll start
pumping it through.
What we're going to do is you're going to pump it up, hold, open the valve, let it bottom
out, close the valve, and then repeat.
Do it about 10 times then we'll check the reservoir.
See where we are.
Yep, time to fill up.
To give it a good chance of getting most of the fluid flushed out, we're going to fill
up the reservoir probably three or four times to really force out that old fluid.
Alright, we'll refill it one more time, pump it down, then we'll set the level.
And the mark we're heading for-- once again I know we have new brake pads on the back
of this one-- we're gonna be heading about right here.
And that'll do.
Let's go ahead and put our cap and diaphragm and little nylon piece back on, and we're
pretty much finished guys.
Alright, now just need to pull the hose off, put that dust cover back on.
Well alright guys, that pretty much wraps this one up.
all that's left for me to do is put the tires back on and get the seat in there.
So, if you need any parts for your machine, why don't you come see us at Partzilla.com
and we can get you taken care of.
If you have any questions or comments, leave them in the section below and I'll do my best
to answer them.
Til next time we just want to say thanks for shopping with us at Partzilla.com and we will
see you in the next video.
Have a great day.