dirty brake fluid resevoir

[Guest]

I'm plugging away working on the brake system on my 1980 GS850 and popped open the resevoir, which was so old I couldn't see into the container until I opened it.

Anyway, here's a photo of all the gunk that was inside. Is this normal? Or is this just really, really old fluid.

- Hector

[hampshirehog]

I wouldn't call it normal but it's not rare to find all that gunk in there. It needs a blo*dy good clean out that's for sure.

[Suzuki mad]

Uuuuurrrrhhhh Yuck......

Thats one dirty master cylinder resevior. Give it a good clean out and bleed some new fluids through. Just think what the insides of the callipers are like.

Suzuki mad

[oldgsfan]

Pulled the calipers

Good point. Actually, I have a new resevoir on order from z1 and plan to order some new brake lines.

Now, it looks like I may need to get one of those caliper rebuild kits. I just took the right side caliper off and popped the piston out.

This is my first brake job on a bike but from what I've read on this site, pitting is a big no no. Well, I found some pitting. I can see about half a dozen pits no bigger than the tip of a needle, but they run along a ridge that would place them around where the O-ring goes.

So, just from what I've read, I'm guessing I need to replace these? Is that right?

And, how do you clean a disassembled brake caliper anyway? Do I leave it to soak in cleaning fluid? There's gunk along where the dust boot was. Can I scrape that off, or should I let it soak a bit?

Thanks for any help anyone can give me on this.

- H.

[Shin-Ken 1074]

The colour of the brake fluid at change over time should be close to the colour it was when it went in, letting it get to that stage is not the best way to maintain your brake system. The fluid should be changed (not just topped up) once a year as a minimum. In areas of major seasonal differences it is better to change the fluid at the start of Winter and the start of Summer to keep the system operating at its best, and to stop the brake fluid turning into custard and doing who knows what to your calipers. Yeah bleeding Suzi brake systems is a pain sometimes, but the result of not having brakes that work is a bit more painful, plenty of info on GSR about system bleeding to help, cheers.

[hampshirehog]

If the pits are the same depth as the seal you'll need to replace the pistons as you could end up with a leak. You'll need to check how far back the pistons sit with new pads and the disc in place - you can't see it all assembled but it's easy enough to work it out from careful measurement.

If you need new pistons go stainless - waaay better.

If you buy new seals either be very sure of your supplier if you go pattern or by OEM. Some seals I've seen have resembled jelly more than rubber.

For cleaning a bit of scrubbing with hot water and washing up liquid does wonders. Just makes sure that it's all 100% dry before you start putting things back together and lube only with brake fluid.

[oldgsfan]

Thanks for all the advice! No good bike supply places near here, so I guess I'll have plenty of time for cleaning while I wait for the mail man.

[Nessism]

Sounds like you are doing the job right; full system teardown instead of just pumping new fluid through, which in my experience is NOT effective.

Teflon/stainless lines are a nice upgrade since you have to replace the lines anyway. Goodrich lines from Z1 are popular or you can build your own from Earl's parts for a reasonable price.

Common method to remove the pistons from the calipers is to use compressed air. Make sure to cover the piston with a rag though or it may shoot out and go flying. Pitting on the piston is bad, particularly if it's in the sweep area of the caliper seal.

I prefer OE brake parts. Lots of sources for these such as Bike Bandit, motogrid, flat out motorcycle, etc.

Good luck.

[Suzuki_Don]

Teflon/stainless lines are a nice upgrade since you have to replace the lines anyway. Goodrich lines from Z1 are popular or you can build your own from Earl's parts for a reasonable price.

Ed what type of construction are the brake lines on your 850 made from? Are they teflon and SS? Are the Z1 Goodrich lines in SS or normal rubber construction. I would have a go at making my own but don't know if the parts are available in OZ. Is there any special trick to measureing them up. I intend to run duals from caliper to MC.

Thanks.

[Nessism]

Ed what type of construction are the brake lines on your 850 made from? Are they teflon and SS? Are the Z1 Goodrich lines in SS or normal rubber construction. I would have a go at making my own but don't know if the parts are available in OZ. Is there any special trick to measureing them up. I intend to run duals from caliper to MC.

Thanks.

Hey Don,

Using old fashioned three line setup on my 850. The cable run is slightly shorter than two full length lines but I have no real good reason to do it this way other than it seems right to me.

Made the lines myself using Earl's components. http://www.thegsresources.com/_forum...d.php?t=114521

They are pretty cheap to make as long as you stay to the regular plated fittings instead of going for stainless. The lines themselves are teflon with a stainless outer covering - this is the standard construction method for almost all the "stainless" lines.

Hope this helps.

Ed

[Suzuki_Don]

Hey Don,

Using old fashioned three line setup on my 850. The cable run is slightly shorter than two full length lines but I have no real good reason to do it this way other than it seems right to me.

Made the lines myself using Earl's components. http://www.thegsresources.com/_forum...d.php?t=114521

They are pretty cheap to make as long as you stay to the regular plated fittings instead of going for stainless. The lines themselves are teflon with a stainless outer covering - this is the standard construction method for almost all the "stainless" lines.

Hope this helps.

Ed

Thanks Ed. I have found an Earl's distributor in Sydney where I live. So will pay them a visit in the next day or so and see what I can find.

Thanks again.

[Suzuki_Don]

Ed, did you use any angled fittings on your brake lines when you made them up or are they straight fittings all round.

[Nessism]

Ed, did you use any angled fittings on your brake lines when you made them up or are they straight fittings all round.

Don,
I used a straight banjo on one end and an angled fitting on the other end.

If you are going to use two separate lines for the front, I suggest you ask your Earl’s guy to quote you one piece of hose 6 feet long, with a straight banjo crimped on each end. When you get the line you then cut it in half and then you only need to install one angled fitting on each of your two lines. Of course, you will need to trim each line to the proper length before installing the hose end. Saves time for you and Earl’s should crimp the lines for roughly the same price as purchasing a bolt-on fitting. Oh, and get the type of fitting that can be rotated – costs about $2 or $3 more but worth it.

Good luck.

[Suzuki_Don]

Don,
I used a straight banjo on one end and an angled fitting on the other end.

If you are going to use two separate lines for the front, I suggest you ask your Earl’s guy to quote you one piece of hose 6 feet long, with a straight banjo crimped on each end. When you get the line you then cut it in half and then you only need to install one angled fitting on each of your two lines. Of course, you will need to trim each line to the proper length before installing the hose end. Saves time for you and Earl’s should crimp the lines for roughly the same price as purchasing a bolt-on fitting. Oh, and get the type of fitting that can be rotated – costs about $2 or $3 more but worth it.

Good luck.

Hey Ed how quick was that reply. You dont remember the angle do you and does the angle go at the top or on the caliper.

Also where do you get the longer banjo bolt that is required for the 2:1 MC connection. Do Earl's sell these and do you know what size thread the 10mm banjo's are for the MC as I noticed on some sites the pitch comes in 1mm, 1.25mm & 1.5mm. Thanks Ed.

[hikermikem]

The MC threads on my 650, 850 & 1100 are all 10mm x 1.00.

I made the same set-up as you are planning: 2 lines from the MC, 1 to each caliper.

I used a 20 degree angle fitting at the caliper, seemed to give better access to the bleeder. Not sure where your banjo sprouts from on your MC, to the left side or from the rear? My rear one accomodated a straight fitting, the left side config uses an angled one.

Use DOT 4 fluid, it has a higher boiling temp than the standard DOT 3. The DOT 5 stuff is silicone based & not compatible with the 3 & 4 stuff.