front brake master cylinder

Moderator: Moderators

Post Reply
djb123456
Posts: 5
Joined: Sat Dec 31, 2011 12:13 pm
My Bike: kymco kr sport

front brake master cylinder

Post by djb123456 »

hi everyone,
bought a zxr l3 and just trying to sort out the front brake.
it only seems to start braking when the lever is just a few centimeters away from the bar.
ive bleeded the brakes and it hasnt made much of a difference.
so iam going to change the parts in the master cylinder could anyone post a pic of how to get it apart plz.

thanks :smt001
cargo
zxr400 oc member
zxr400 oc member
Posts: 3341
Joined: Sat Jan 08, 2005 10:33 am
My Bike: tomos moped
Location: Carrickfergus Northern Ireland

Re: front brake master cylinder

Post by cargo »

You'll find a good exploded drawing in the manual.



http://www.zxrworld.co.uk/zxr400/manual.html
hatatfatcat
Posts: 51
Joined: Sun Jan 11, 2009 12:29 pm
My Bike: ZXR400H
Location: Peel Isle of Man
Contact:

Re: front brake master cylinder

Post by hatatfatcat »

poke!
Image
User avatar
Mori Man
Blingmeister
Blingmeister
Posts: 1976
Joined: Thu May 10, 2007 3:30 pm
My Bike: ZXR400J2
Location: JAPAN

Re: front brake master cylinder

Post by Mori Man »

What's the span adjuster set at ?
Nothing worse than having an H and not being able to scratch it !
Living life on the edge, SuPposedly
cargo
zxr400 oc member
zxr400 oc member
Posts: 3341
Joined: Sat Jan 08, 2005 10:33 am
My Bike: tomos moped
Location: Carrickfergus Northern Ireland

Re: front brake master cylinder

Post by cargo »

hatatfatcat wrote:poke!

Poking in an activity that is restricted to Facebook................any further poking on ZXRworld will result in a week long ban

Admin power...................... :excited :excited
User avatar
Mori Man
Blingmeister
Blingmeister
Posts: 1976
Joined: Thu May 10, 2007 3:30 pm
My Bike: ZXR400J2
Location: JAPAN

Re: front brake master cylinder

Post by Mori Man »

cargo wrote: Poking in an activity that is restricted to Fanny ................ any further poking on ZXRworld with out video will result in a week long ban
:smt003
Nothing worse than having an H and not being able to scratch it !
Living life on the edge, SuPposedly
djb123456
Posts: 5
Joined: Sat Dec 31, 2011 12:13 pm
My Bike: kymco kr sport

Re: front brake master cylinder

Post by djb123456 »

Mori Man wrote:What's the span adjuster set at ?
i thinks its at 1. why would this affect it?
hatatfatcat
Posts: 51
Joined: Sun Jan 11, 2009 12:29 pm
My Bike: ZXR400H
Location: Peel Isle of Man
Contact:

Re: front brake master cylinder

Post by hatatfatcat »

cargo wrote:
hatatfatcat wrote:poke!

Poking in an activity that is restricted to Facebook................any further poking on ZXRworld will result in a week long ban

Admin power...................... :excited :excited
you started it with the txting
Image
User avatar
Tirpitz
zxr400 oc member
zxr400 oc member
Posts: 766
Joined: Sun Dec 12, 2010 2:45 pm
My Bike: Kawasaki ZXR400L4
Location: Doncaster, South Yorkshire

Re: front brake master cylinder

Post by Tirpitz »

djb123456 wrote:
Mori Man wrote:What's the span adjuster set at ?
i thinks its at 1. why would this affect it?
Because it makes the lever further away or closer to the bar to start with, so adjusting the available travel.

IME the front brake is a PITA to bleed properly. You will usually find microscopic bubbles trapped in the lines, splitter and also at the MC. You won't get these clear by the usual method of pumping with the brake lever. Your best bet is to get a vacuum bleeder to draw fluid through - that works.

Another way (but which takes longer) is to bang all the lines with a spanner to try and dislodge the bubbles. Leave the bike overnight with the bars turned so that the MC banjo is at the highest point so that the air can collect there (you will also probably already have some air trapped there which you wont dislodge). Then in the morning BEFORE TOUCHING THE BRAKE LEVER AT ALL crack open the MC banjo THEN pull the lever gently to push out the air. Tighten up before releasing the lever. Repeat as necessary. That generally clears it. You may need to repeat this once you've run the bike on the road as you may find some remaining bubbles collect at the MC banjo again.

IME Kwak front brakes take a lot of mucking about to bleed properly. Not difficult but takes patience.

If you want to rebuild the MC it's easy. Once the lever is off remove the rubber dust boot from the end of the MC piston and you will see a circlip in the recess. Remove and the MC piston pulls out. A rebuild kit will comprise new piston and seals (one of which you need to fit to the piston yourself), spring and new boot. Don't waste money on the OEM item, the pattern one from Wemoto is excellent quality and works A1. Replace in reverse order, fill system and bleed as above.

If you've got OEM rubber brake lines on and the bike is several years old and these have not been replaced the brakes will probably be spongy no matter what you do. Rubber lines have a service life. Replace with braided - they last for ever.
ZXR400 L4, purple / black / pink
Hel braided hoses
Pirelli Diablos
Ohlins steering damper
A16 carbon fibre exhaust can
Nitron Sport shock
djb123456
Posts: 5
Joined: Sat Dec 31, 2011 12:13 pm
My Bike: kymco kr sport

Re: front brake master cylinder

Post by djb123456 »

Tirpitz wrote:
djb123456 wrote:
Mori Man wrote:What's the span adjuster set at ?
i thinks its at 1. why would this affect it?
Because it makes the lever further away or closer to the bar to start with, so adjusting the available travel.

IME the front brake is a PITA to bleed properly. You will usually find microscopic bubbles trapped in the lines, splitter and also at the MC. You won't get these clear by the usual method of pumping with the brake lever. Your best bet is to get a vacuum bleeder to draw fluid through - that works.

Another way (but which takes longer) is to bang all the lines with a spanner to try and dislodge the bubbles. Leave the bike overnight with the bars turned so that the MC banjo is at the highest point so that the air can collect there (you will also probably already have some air trapped there which you wont dislodge). Then in the morning BEFORE TOUCHING THE BRAKE LEVER AT ALL crack open the MC banjo THEN pull the lever gently to push out the air. Tighten up before releasing the lever. Repeat as necessary. That generally clears it. You may need to repeat this once you've run the bike on the road as you may find some remaining bubbles collect at the MC banjo again.

IME Kwak front brakes take a lot of mucking about to bleed properly. Not difficult but takes patience.

If you want to rebuild the MC it's easy. Once the lever is off remove the rubber dust boot from the end of the MC piston and you will see a circlip in the recess. Remove and the MC piston pulls out. A rebuild kit will comprise new piston and seals (one of which you need to fit to the piston yourself), spring and new boot. Don't waste money on the OEM item, the pattern one from Wemoto is excellent quality and works A1. Replace in reverse order, fill system and bleed as above.

If you've got OEM rubber brake lines on and the bike is several years old and these have not been replaced the brakes will probably be spongy no matter what you do. Rubber lines have a service life. Replace with braided - they last for ever.


thanks Tirpitz. ive ordered the master cylinder repair kit and goodridge front race braided pipes. once ive fitted them ill vacuum bleed them and hope they work then.
no doubt ill find something else to work on after the brakes, it seems to be one step forward two steps back :smt012

thanks :smt001
lacos
Posts: 7
Joined: Thu Apr 21, 2011 6:59 pm
My Bike: zxr l5

Re: front brake master cylinder

Post by lacos »

1have same sort of problem hell lines new seals in calipers got pressure but the leaver will come to the bar it gets firmer if i pump the lever a few times is this the master cylinder or have i still got air in the system ?????? thanks
User avatar
CaNsA
zxr400 oc member
zxr400 oc member
Posts: 1741
Joined: Sat Nov 29, 2008 4:02 pm
My Bike: ZX6R F1
Location: Liverpool

Re: front brake master cylinder

Post by CaNsA »

Helpful hint.

Put the bike on the sidestand, not a paddock stand,and turn the bars on full left lock when bleeding the brakes.
Any bubbles trapped in the m/c will rise into the res.
Moderator & Skilled Ban Hammer Operator!
Has this forum helped you out? Say thanks by donating some of your hard earned cash towards running costs.

:: <=-LOADED TELLY BOXES - NO CONTRACT - NO SUBSCRIPTION - PM ME-=> ::
lacos
Posts: 7
Joined: Thu Apr 21, 2011 6:59 pm
My Bike: zxr l5

Re: front brake master cylinder

Post by lacos »

well ive now tied the lever in the on position will leave over night then bleed them again and thanks
Post Reply