More corroded brake system parts

[Nessism]

Working on another GS clean up (GS850 this time) and both front brake calipers have corrosion pitted pistons, the master cylinder bore is corrosion pitted, and the entire system is full of brown gelling brake fluid. The rear was in better shape; no pitting but the fluid was all brown and chunky.

For all you guys bringing back these long off the road GS's, please make sure you do a full system tear down to clean out all the old fluid and inspect the metal parts for corrosion pitting. Flushing does NOT get all the chunks out plus, you may have damage lurking so it's best to refurb the system properly by performing a full tear down. If you need pistons/seals, only use OE parts, not that K&L crap that normally reputable places like Z1 sells. Replacing all the seals is generally recommended, but not strictly necessary as long as the system wasn't leaking before. Also, replace those old rubber brake lines. They gather a layer of scum on the inside so even if you clean the calipers and master, the scum will contaminate your clean brake fluid when you refill. Suzuki calls for replacing the brake lines every two years, which obviously is excessive, but if your bike still has the rubber lines installed you should be aware that you are about 28 years overdue for this maintenance.:-\\\

 

[jwhelan65]

+1, I ended up with a complete tear down on the 700. Replaced one caliper bore and ordered all new pistons and seals. I think it cost me $200.00 total in parts, also replaced the lines with SS at the same time.

Well worth the time and money

 

[hampshirehog]

Ed - use stainless pistons. Problem of pitting solved forever!

 

[Nessism]

Ed - use stainless pistons. Problem of pitting solved forever!

I don't think they are available over here, plus I'm not sure it's good to run pistons that don't take dust boots.

Do car brake caliper pistons have dust boots? Maybe I'm concern over nothing?

 

[twr1776]

Today 01:22 PM Nessism Quote: Do car brake caliper pistons have dust boots? Maybe I'm concern over nothing?

Ed, the auto calipers I have worked on before have all had rubber dust boots.

This is the link to the photo I posted before on caliper innards. I agree that a full caliper rebuild should be part of any "new to me" bike purchase. Brakes, tires, and supension are NEVER places to get cheap on.

Everyone wants to mod theses bikes up for speed but if you cannot brake safely or manuver properly to avoid a road hazard you are not very bright IHMO.

BTW these caliper photos are from a one owner always garage kept above freezing temperatures bike.

http://www.thegsresources.com/_forum/showthread.php?t=140098

 

[salty_monk]

I don't see a problem with no dust boots if they're stainless pistons, the seal will ultimately keep the crud out of the caliper I think the boot is to keep the worst of the water out...

If it's one thing the English are good at it's dealing with corrosion... living on an island with generally bad weather, rain, humidity & using salt in the winter rather than winter tyres means it's necessary.

The really cold countries such as Iceland etc actually have less issues as they use no salt but use snow tyres & chains etc instead. I guess the fact that the weather in England is not consistent makes that difficult!

Dan

 

[Dogma]

Dust boots will also theoretically keep out combinations of crud including sticky road goo full of grit that may abrade the seal when you back it up for the next pad change. Don't forget to clean it, and things will probably be fine. But then, the plated pistons made it 30 years and would have gone longer if they had been maintained too.

 

[hampshirehog]

None of the modern bikes I've worked on recently have dust boots. Indeed, there was / is a train of thought over here that the dustboots retained moisture which hastened the rusting process. I don't know whether or not I subscribe to that theory but it's worth bringing up. Certainly some mainstream garages stopped putting on boots back in the day.

Dogma is right though about pad changes - the exposed pistons do get covered in road goo / pad dust and need to be cleaned before being pushed back in.

And Dan - it hasn't rained here for weeks. Sunnier than the Bahamas apparently (so it's bound to start raining now....). Also no need to worry about the salt any more. All the councils ran out with the snow we had in January and with the massive cuts in public spending being announced you can bet the first thing they'll cut is buying salt (better to spend it on the one-legged lesbian day centres......).

Having said that, we can get stainless pistons that take the boots. It's just that the bootless RGV rears are cheaper than the pattern stainless rears. Top pic is the stainless, bootless RGV rears, bottom pic is pattern stainless, booted fronts for the GSX1100ET. I popped the boots on the front to help with future pad changes (plus I had some new boots anyway).