THE KAWASAKI TWIN OWNERS FORUM

[Gryph]

So I'm finally getting to work on the 79 that I bought for 300 bucks this summer. So far I've changed the plugs, and put in new gas, that alone was all that was needed to get it to fire up. Also changed the clutch cable which was broke, and I've done some extensive cleaning (30 years of grime).

I opened the front master cylinder the other day and the fluid is looking pretty awful, also the front brakes squeal a great deal under light braking.

So I figure I need to at minimum replace the brake fluid. Probably replace the brake pads, and possibly replace the lines/rebuild the master cylinder.

So I suppose I'm asking what you guys would do LOL, and where to source my parts. When I tried to get the clutch cable the local dealer told me to buy a newer bike (ended up getting it from Z1), so I figure I'll have to order what I need from the internet. I don't see the pads listed on Z1, any ideas for those??

Here's a pic of the beast all polished up...

[liquidwrench]

Welcome to the forum, Gryph.

So do the brakes squeal when you use them, or all the time? If they're dragging then dismantle the caliper and clean it up. If that doesn't work then do the same for the master cylinder, making sure the passages in there are clean. While you have things apart blow out the brake line. Sometimes rubber lines can swell and cause the brake to drag.

Otherwise sand the pads a bit - they have been sitting awhile and the surface is oxidized.

If the pads are soaked in fork oil you can try to clean them up with lacquer thinner, or buy new ones online. Try Z1 enterprises, bike bandit, etc. Unless your bike has lots of miles you probably don't need pads.
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RD
1977 kz400 D4
1978 kz400 A2 parts bike
1983 Hyster J25A "Stable Mabel"
Stihl 020
'70 R75/5, '91 FXRP, '60 FLH past bikes
CB400F - new project

[faffi]

On old bikes, it's a good idea to strip, clean and inspect every part of the braking system - it could save your life one day. Especially the master pump cylinder bore tends to corrode badly if brake fluid hasn't been replaced regularly, which could lead to total loss of front brake at the worst possible moment.

Bike looks good, though
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Odd Ivar - gone, but not forgotten

[Biquetoast]

In my short personal biking experience, the squeaking is most likely caused by un-even brake piston movement, likely caused by years of caked-up crap around the o-ring and seal around the piston.

You'll remove the caliper, disassemble, blow the piston out with compressed air, gently remove the o-ring and seal, and stare in amazement as you pick the disgusting crud out of the seal beds. Re-assemble, bleed, smile, stop quietly.

It's almost that simple...


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(1.) '75/'76 KZ400D - Commuter
(2.) '78 KZ750B3 Twin - Commuter
(3.) '78 KZ750B3 Twin - Commuter
(4.) '75 KZ400D - Sold and gone
http://kz750.com

[d5nuke]

Gryph,

There is a set of pads on ebay right now for your bike for like 10 bucks new in the box just to let you know.
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If it is not broke Then fix it till it is....
1982 kz440 ltd

[goofin]

the master cylinder kit is available from Z1 as well. you need a long reach pair of ring pliers but its easy to do. flush all the lines too.
_________________
1976S2
1979B
2005 kz400 custom bobber
The democracy will cease to exist when you take away from those who are willing to work and give to those who would not.
Thomas Jefferson

[nunrleft]

denniskirk.com has them for $28.95
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--------------------------------
1987 VF700C Super Magna
1982 KZ440 LTD D4

http://www.minnesotahomeinspectors.com

[Gryph]

Wow thanks for all of the quick replies.

To answer some questions:

The brakes don't seem to be dragging at all, and the bike brakes "fine" (only had her around the neighbourhood less than 100km/h), just squeal when light pressure is applied (most noticeable when moving the bike around).

I was kind of hoping that the brakes were in decent shape, as this bike was ridden up until October 2007 by the previous owner (then he broke the clutch cable and gave up on it)... However the brake fluid now leads me to believe that it has seen some neglect.

Bike has ~35 000kms (21, 875 miles) on it, so the pads should still be fine??

I suppose I'll end up tearing her apart soon enough, I just wanted to order all that I needed before I did.

I'm thinking the master cylinder kit might be a good idea?

Thanks again guys.

[PxTx]

I've never really had any concern with brakes squealing, as long as the pads are in good shape. Most of the more aggressive race pads I have run on cars tend to squeal with light to moderate pressure.

I also have a few SOHC CB750 Hondas. They run a Stainless Steel rotor and typically squeal in similar conditions. So I've accepted this is a function os some brake systems. If the pads a and rotor surface is flat, you could try and use a hack saw blade or similar item to cut a small dust channel to allow any brake dust to be swept off the surface between the rotor and pad. Sometimes that can cause squealing. Most modern pads have this already designed in.

Please note, I am new to the KZ400 forum and the bike. I do not have much intimate knowledge of these bikes, but am offering you my real world experience from things I am familiar with. Good Luck!

[Gryph]

Here's a pic of the master cylinder guys, looks pretty ugly...

It's freezing in my garage right now so I haven't really torn into anything yet, still have to check out the pads...

[le formal loic]

hello

for your research over Z1 enterprise, looks on ebay motors, there are many parts to our kz400 motorcycles.
New or worn
http://motors.shop.ebay.com/items/KZ400_W0QQ_sopZ1

http://motors.shop.ebay.com/items/KZ400_W0QQLHQ5fSellerWithStoreZ1QQ_flnZ1QQ_sasZ1QQ_sopZ1?_trksid=p4506.c0.m276
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Z400 D4 77
Z400 D4 1977 170km/h

[Bodo]

[Bodo]

[thxone]

I'd do a brake fluid transfusion...what do I mean? I mean get a large bottle, the biggest you can find, of some fresh brake fluid, a Tupperware container, or two if dual front brakes, some CLEAR vinyl tubing the same size as your brake bleeder(s) and a wrench for the bleeder(s). Put the bike on the center stand. Place the Tupperware container(s) on the ground directly below the brake caliper(s) and fill it/them 1/4 full of fresh brake fluid. The container(s) don't need to be big, 6 inch by 6 in by 3 inch will do. Connect the CLEAR vinyl tubing to the bleeder(s) and the other end submerged in the fresh brake fluid in the Tupperware. The tubes need to be long enough to reach so the ends will rest in/under the fluid on their own.

Remove the master cylinder cover, crack the bleeder(s) open, add the fresh brake fluid to the master cylinder till it's full and begin pumping the brake lever fully and slowly. You should see the old dark fluid entering the Tupperware. When the fluid in the master cylinder reaches 1/4-1/2 full add some more fluid to top it off (DON'T PUMP IT DRY) now continue until only fresh clear fluid is seen in the clear vinyl tubes, adding fluid as needed to keep the master cylinder topped off then close the bleeder(s) tightly to spec. Remove the tube(s) and discard the fluid in the Tupperware...keep the tubes as they can be reused. Pump the brake lever, it should feel tighter than before. If needed, top off the master cylinder, put the cover on and you are done with the transfusion...if these directions are followed you should have no air in your brake system and all new fluid.
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'82 KZ440 LTD A3
Averaging 50mpg...45...55....22....60!!

[stfn]

firstly,