How to bleed Shimano Brakes
How to Bleed Hydraulic Brakes - Shimano® Flat Bar Levers
0:00 / 0:00
Quality:
Sharing buttons:
this video will review hydraulic brake
cleaning for Shimano brakes using the
Park Tool bkm 100 brake bleed kit we
will concentrate on systems using flat
barred levers for Shimano drop power
levers and for other brake brands see
our video playlist here brake bleeding
requires a thorough technical knowledge
of the braking system if in doubt or if
your procedure is not working
contact the brake manufacturers website
for their model specific information it
is important to always use the
appropriate brake fluid for the brake
being serviced never use a deal t fluid
for brakes designed for mineral oil
conversely never use a mineral oil and
brakes design for a deal t fluid mixing
fluids can cause damage to the
components and lead to brake failure
additionally you should never share
bleed kits between do t fluids and
mineral oils you may also want to
anticipate any advertent spills and
drips on the floor dispose of any fluid
in accordance with your local waste
disposal authorities typical tools and
supply for this procedure include the
PKM 1 hydraulic brake bleed kit from
Park Tool appropriate mineral oil for
the system hex wrenches 7 millimeter
wrench park tool piston press pp 1.2
tire levers or cone wrench clean rags
isopropyl alcohol spent fluid container
such as a bottle or a bag angle finder
toe strap and zip ties safety glasses
and gloves we're going to use this
Shimano XT mm 8000 to walk through the
process there's always going to be new
models so be sure to check the
manufacturers website for the most
up-to-date information for Shimano that
is si Shimano com inspect a lever for a
reach adjustment screw it can be located
here or out here bring the lever away
from the grip as far as it will go
return it to the users preference after
the bleed some lever models also have a
free stroke adjustment screw
from all the way tight turn it three or
four turns counterclockwise remove the
wheel rotate the bike so there is
consistent uphill travel from the
caliper to the lever for front brakes
this positions fine on rear brakes the
bike may need to be tilted lower the
stand as necessary remove brake pads
from the caliper store in a clean spot
we set the Pistons back into the caliper
body install bleed blocks between the
Pistons hold the block in place using
the pad screw from the caliper finger
tight is fine completely remove the
cover from the bleed nipple and store
this in a clean spot note the caliper
bleed location may vary here it is an
internal nipple below a cover and here
it is on top of the body if working on
the front caliper it is sometimes better
to remove it from the mount this allows
better access to the external bleed
nipple
I put the lever locate the bleed port
screw remove the screw and check for the
o-ring put these in a clean place the
lever port screw is an m5 thread the
same thread on the bleed funnel
however if you first thread the funnel
into the purple adapter also an m5
thread it makes it easier to correctly
align the threads use care not to cross
thread the adapter gently snug the
adapter remove stopper from bleed funnel
viewing the bike directly from the side
take note of the bleed funnels vertical
alignment rotate the lever is necessary
until the funnel is it 45 degrees
forward from vertical attach the syringe
holder above the caliper
now I'll prepare the syringe find the
hose with one threaded end and one open
end thread this onto the syringe
snugging it gently slide the compression
sleeve over the end of the hose
pull it up toward the syringe fill the
syringe about two-thirds full with the
appropriate brake fluid hold syringe
upright and pull back to clear the
tubing now slowly and carefully push the
plunger until the fluid just comes to
the end of the tubing place the syringe
into the syringe holder place a seven
millimeter box end over the nipple push
the hose end securely over the nipple or
external nipples use the compression
sleeve to help secure it use the wrench
to open the nipple one half turn with
calipers with the bleed screw loosen the
bleed port screw one half turn push
almost but not all of the fluid into the
caliper through the system and up to the
bleed funnel look for any bubbles
appearing in the funnel that indicates
air from the system is being expelled
the fluid was dirty continuing to push
until you see clean fluid entering the
bleed funnel close the bleed nipple at
the caliper now the syringe can be
removed from the caliper pull back a
little on the syringe as you disconnect
it from the caliper this minimizes
dripping remove the syringe holder the
fluid in the funnel was dirty install
the stopper remove funnel and dispose of
the dirty fluid install funnel into the
lever remove stopper and refill the
funnel over half full with fresh fluid
the next step is to reverse the flow of
the fluid from the bleed funnel downward
and out the caliper select the hose that
has no fittings on either end install
the compression sleeve on one end
install the other end into a waste
disposal bag or other receptacle secure
the hose inside the bag with the zip tie
place a seven millimeter box and over
the nipple attach the hose to the bleed
nipple for external nipples use the
compression sleeve to help secure it be
sure the bleed funnel is more than half
full loosen the caliper bleed nipple 1/2
turn squeeze the lever gently to start
the flow of fluid from the bleed funnel
down to the caliper and through the hose
into the disposal bag temple on the
length of the hydraulic hose to
encourage any bubbles to dislodge keep
an eye on the bleed funnel do not let
the funnel run out of fluid and fluid is
necessary to avoid letting any air into
the brake lever port but no more bubbles
appear in the drain hose close the
caliper bleed nipple note you may not
see bubbles during this part of the
bleed leave the funnel and bleed hose in
place if necessary refill the bleed
funnel to about half full pull the lever
to maintain pressure on the Pistons hold
the lever to the handlebars with a strap
or zip tie or have someone hold it for
you now quickly open and close the
caliper bleed nipple once pressure will
be lost at the lever as the fluid is
forced out the nipple this one the strap
Andry pump the lever until it again
feels firm retighten the strap
repeat the quick opening and closing of
the caliper bleed nipple
now remove the strap from the lever the
caliper work is done remove the bleed
hose type the bleed nipple to a torque
of about 4 to 6 Newton meters install
the caliper bleed cover squeeze the
brake lever it should feel firm now if
not there's still air in the system if
necessary repeat the bleed from the
beginning reassessing your process the
system should be free of air from the
caliper and the brake line however there
still can be bubbles at the lever just
below the part rotate the lever so the
funnel is not 30 degrees back from
vertical squeeze and release the lever a
few times while inspecting inside the
funnel for any burp or bubbles now
rotate the lever so the funnel is 30
degrees forward a vertical for a second
burp position again squeeze and release
the lever to clear any remaining bubbles
and there are no bubbles appearing from
either tilted position rotate the lever
until the funnel is vertical plug the
funnel and remove it and the adapter
from the lever always check that the
adaptor oring did not get left behind in
the lever installed lever bleed screw
with a ring and secure this mild torque
of about 1 Newton meter
return the lever to a writing position
and secure remember also to turn the
lever reach and free stroke adjustment
to their original settings remove brake
block and clean lever and caliper with
rag and alcohol if removed reinstall the
brake caliper install brake pads install
the wheel now pull the lever repeatedly
to bring the pads to the rotor recenter
brakes as necessary after bleeding
remove hose from syringe and remove
adaptors from the hose let the hoses
drain make sure any hose clips are open
a little remnant mineral oil in the
syringe is not an issue otherwise the
syringe can be taken apart to be cleaned
at your discretion thanks for watching
you can find hundreds more videos like
this one on our channel here on youtube
and we're constantly working on more so
be sure to subscribe for the latest
content for Park Tool and check out our
website which has even more content to
help you make your bike better
