Spent some time in the "man-cave" - From Wreck to Restoration

[waterman]

Cliff, you will need to use brake caliper grease on the pins (parts 9 and 10). It is not the same as your axle grease, it is specifically made for lubricating brake parts. I believe it is a silicone based synthetic, not a petroleum based grease like your axle grease. Most auto parts store will carry it, sometimes in small single use plastic packets.

I think the others are suggesting using brake fluid to reassemble the pistons into the caliper. Chef mentioned the silicone for the rubber bushings (part 11). These are both excellent suggestions.

It looks like you are moving right along with your renovation, thanks for documenting the progress. +1 on the blue, I have been contemplating a color change for one of my bikes and may go that way.

[BassCliff]

Thanks Mr. waterman,

Oh boy! Another trip to the parts store.

But, yeah, might as well put it back together with the right stuff and not worry about it. I'll need caliper axle grease for when I redo the rear brakes anyway.

Thank you for your indulgence,

BassCliff

[rapidray]

Sorry for the confusion Cliff. I meant to use brake fluid for lubricant on the piston seals when reinstalling the pistons in the calipers. I need to state things more clearly in the future. I find myself at times not adding specifics enough. Ray.

[BassCliff]

Thanks Ray,

No harm done. I kinda figured that was the case. Use brake fluid on the piston and silicone on the caliper axles. I'll keep you informed.


Thank you for your indulgence,

BassCliff

[glstine]

Cliff - How do you like the L exhaust on there? I've got an '80850G project I'm just starting and I need an exhaust and there is an L available and was wondering how it looked with the G trim.

[BassCliff]

Cliff - How do you like the L exhaust on there? I've got an '80850G project I'm just starting and I need an exhaust and there is an L available and was wondering how it looked with the G trim.

Hi,

It looks OK, just different. The "L" exhaust has more of a trumpet flare on the end and it seems a few inches shorter.

I know it looks different without the body parts, but here's a shot of the "L" exhaust...



And here's a shot of the stock exhaust...



I'll post up more pictures when I get my bike all back together. I'm working on the brakes right now and still haven't put the body parts back on.


Thank you for your indulgence,

BassCliff

[BassCliff]

Hi,

And speaking of brakes. I took my calipers to the garage at work today so that I could blow out the pistons with their air compressor. Here's what the pistons looked like...



The pistons are smoother than they look in the picture.

And here's a shot of the worst caliper bore (the other one wasn't nearly as grunged up)...



A closer shot...




I'm really hoping to clean up these parts and reuse them. Should I use fine steel wool or some kind of really fine emery paper to smooth off the aluminum oxidation?


Thank you for your indulgence,

BassCliff

[chef1366]

Good luck
I'd replace them though. The whole shebang.
Are there pits on the bore? Those aren't pits on the pistons my eyes see?

[BassCliff]

Hi Bill,

Here's another picture with the pistons cleaned up a little better...



But there are a couple of spots where they feel rough when I scrape my finger nail across them. I should probably replace them. Thanks for looking.


Thank you for your indulgence,

BassCliff

[rustybronco]

Those pistons are junk. replace them.

[Dogma]

Cliff, good to see the progress. The blue is sweet!

From the photos, I can't render an opinion on the calipers. Yeah, the bores are a mess, but the piston only needs to run straight and smooth with no hangups. If you can clean the corrosion out of the bore and still have good metal around most of the bore (I'm thinking 75% clean up), I think they will be OK. What needs to be more like perfect is the seal grooves. Those aren't really visible in the pics.

When I rebuilt my 850's brakes, I ended up going through 4 calipers to find 2 good ones.

[Nessism]

Yup, pistons are junk.

Corrosion down in the caliper bore is no big deal as long as the groove for the seal doesn't have any deep damage which will provide a leak path.

[BassCliff]

Thanks guys,

OK then, it's settled. I needed to order some exhaust gaskets anyway. I didn't replace them and I have a feeling that I'll need them. Drat. More waiting. I guess I'll start on everything else and do the brakes last.


Thank you for your indulgence,

BassCliff

[salty_monk]

I have some complete calipers left off the 83750ES if they'll fit...

Dan

[BassCliff]

I have some complete calipers left off the 83750ES if they'll fit...

Dan

Thanks Dan!

The caliper assemblies have different part numbers:

'80 GS850 = 59100-45200 superseded by 59100-45280
'83 GS750ES = 59100-45210 superseded by 59100-45211

The part number for the holder is different too. But they look very similar and they use the same pistons and EBC pads as mine. They might fit so I'll PM you.


Thank you for your indulgence,

BassCliff