1978 GS1000 Brakes

[Apples]

So I got my bike to run the last night so time to start ordering parts! 

 

So far, I know it has to have brake parts.  There is no fluid in them and they are totally seized up.  I can pull on the front brake and push on the back and they don't move.  I did a little looking around online for parts and the most I found is rebuild parts for the master cylinders, a caliper here and there, and plenty of brake lines and pads.  Assuming that I need all new parts, where is the best place to find parts? How hard is it to rebuild the master cylinders and calipers? I've rebuilt wheel cylinders and calipers on cars so I can't imagine it being too much different.  There doesn't seem to be too many parts on the master cylinders either so I would imagine I could rebuild them too.  

 

I know there is some differences in the GS1000 with a single front brake and a double.  Mine has the single front brake.  Are the brake parts different between the two? I am also from northern Illinois if that makes any difference in ordering parts. 

 

I plan on documenting the whole bike rebuild so hopefully I'll remember to take lots of pictures to post on here.  

[BigT]

Buy OEM parts for your brakes

The after market parts, especially K&L, are crap

The single disc model has a different master cylinder, it easily noted in the parts fiche

Replace the brake lines with steel braided ones.

Order from Babbits or Partshark or Parts Outlaw. Avoid Bike Bandit

[Apples]

10 minutes ago, BigT said:

Buy OEM parts for your brakes

The after market parts, especially K&L, are crap

The single disc model has a different master cylinder, it easily noted in the parts fiche

Replace the brake lines with steel braided ones.

Order from Babbits or Partshark or Parts Outlaw. Avoid Bike Bandit

Awesome. I was looking at Babbitt and Bike Bandit. I’ll check out the other two and avoid bike bandit. I’m guessing it’s going to be a total rebuild of the brakes which I expected that anyway coming from the automotive world. I’m just a little lost when it comes to motorcycles. 

[Gixer1460]

They all work exactly the same - cars / bikes / trucks only difference is what limb activates them and no servo assistance on bikes! Only word of caution - if you are not confident of an acceptable outcome - get someone who is! Brakes really are 'life & death' type devices! 

Use Alphasports for part diagrams and parts prices / availability, Some of the images can be a little poor but they are from original Suzuki parts microfiche's so it's understandable!

[Apples]

4 hours ago, Gixer1460 said:

They all work exactly the same - cars / bikes / trucks only difference is what limb activates them and no servo assistance on bikes! Only word of caution - if you are not confident of an acceptable outcome - get someone who is! Brakes really are 'life & death' type devices! 

Use Alphasports for part diagrams and parts prices / availability, Some of the images can be a little poor but they are from original Suzuki parts microfiche's so it's understandable!

I figured they would be about the same but just look a little different. I’m pretty sure and confident on my ability to rebuild them and they will be extensively tested before the bike actually hits the road. I lost brakes once on my first car the day after I bought it and never want that to happen again. It drives me nuts when people want to argue with me when I tell them they need brakes on their car and they think they don’t. 

[Gixer1460]

Don't worry about them - you won't know them very long! 

[Captain Chaos]

Yeah but they might also kill someone you know and not just themselves. 

[Gixer1460]

1 hour ago, Captain Chaos said:

Yeah but they might also kill someone you know and not just themselves. 

unlikely if they live in 'merica where thinking like that is common - vehicle inspection there seems to consist of making sure its still parked outside, which without brakes, could be doubtful LOL!

[Apples]

2 hours ago, Gixer1460 said:

unlikely if they live in 'merica where thinking like that is common - vehicle inspection there seems to consist of making sure its still parked outside, which without brakes, could be doubtful LOL!

It can be pretty amazing what I see at times and what people say when I suggest a repair. Usually with brakes and really bad tires I let them know they are less than the legal limit and tell them it has to be towed from the shop if it’s not repaired. I can’t let something like that leave knowing it’s on the road after being in my shop. 

[Poldark]

On 8/13/2020 at 1:13 PM, Gixer1460 said:

unlikely if they live in 'merica where thinking like that is common - vehicle inspection there seems to consist of making sure its still parked outside, which without brakes, could be doubtful LOL!

50 states, 50 different inspection standards ranging from fairly stringent to none at all.  Even in states without a vehicle inspection program, the vast majority of traffic collisions are caused by operator error and not faulty equipment.

[Apples]

15 hours ago, Poldark said:

50 states, 50 different inspection standards ranging from fairly stringent to none at all.  Even in states without a vehicle inspection program, the vast majority of traffic collisions are caused by operator error and not faulty equipment.

I’m in a no inspection area. Kind of nice really. If I go 30 miles east, all vehicles are inspected once a year. 

[RickLee]

Rear brake pedal pivot is usually rusted so tight you need a sledgehammer and a bunch of wd40 to pop it out.  Clean it, fine sand and polish it. Same goes for the tube it slides into. Use a long lasting grease before you reinstall.  I’m considering drilling a hole and putting a zirk  fitting into mine.  Took a while to fix this.  The rear master. Cylinder is a fairly easy rebuild but the caliper seals and boots are quite difficult.  I know from experience.  To remove the frozen pistons use compressed air hose with a rubber tip. Be sure to place a piece of wood under the piston or it will pop out like a bullet into your caliper.

[Gixer1460]

and take your finger off, if it happens to be in there!

[Apples]

10 hours ago, RickLee said:

Rear brake pedal pivot is usually rusted so tight you need a sledgehammer and a bunch of wd40 to pop it out.  Clean it, fine sand and polish it. Same goes for the tube it slides into. Use a long lasting grease before you reinstall.  I’m considering drilling a hole and putting a zirk  fitting into mine.  Took a while to fix this.  The rear master. Cylinder is a fairly easy rebuild but the caliper seals and boots are quite difficult.  I know from experience.  To remove the frozen pistons use compressed air hose with a rubber tip. Be sure to place a piece of wood under the piston or it will pop out like a bullet into your caliper.

Awesome. Thanks for the advice. First time I took a caliper apart I launched a piston across the shop. 

[RickLee]

I was also told that honing those caliper cylinders is not a great idea, just a very meticulous cleaning and scraping off the hardened hunk carefully... Does anyone else agree with this?  Or is it ok to hone these?

[Swiss Toni]

Take your grease gun nozzle off the gun. Screw the hose gently into the caliper. Pump! 99.99% of pistons will come out. No fuss!

[Gixer1460]

1 hour ago, RickLee said:

I was also told that honing those caliper cylinders is not a great idea, just a very meticulous cleaning and scraping off the hardened hunk carefully... Does anyone else agree with this?  Or is it ok to hone these?

A brass wire wheel is about as abrasive as you want to use - aluminium to soft for 'honing' - get the gunk / rust off, clean seal grooves, job done.

[Captain Chaos]

7 hours ago, Gixer1460 said:

and take your finger off, if it happens to be in there!

This^^^
once i witnessed someone trying to stop the pistons with his fingers. 
The pistons won. 

[Apples]

2 hours ago, Swiss Toni said:

Take your grease gun nozzle off the gun. Screw the hose gently into the caliper. Pump! 99.99% of pistons will come out. No fuss!

That’s an awesome idea. 

[Apples]

22 minutes ago, Captain Chaos said:

This^^^
once i witnessed someone trying to stop the pistons with his fingers. 
The pistons won. 

I’m glad that in my auto classes that I teach that you just replace calipers and not rebuild them. I kept a good core as an example that the piston just slides out by hand now to show the students. 

[RickLee]

10 hours ago, Apples said:

I’m glad that in my auto classes that I teach that you just replace calipers and not rebuild them. I kept a good core as an example that the piston just slides out by hand now to show the students. 

When you get a load of the price of NEW calipers.... wow.  Are there any reasonably priced aftermarket calipers for 1980 GS1000?

[Apples]

9 hours ago, RickLee said:

When you get a load of the price of NEW calipers.... wow.  Are there any reasonably priced aftermarket calipers for 1980 GS1000?

Not that I have seen. These are getting rebuilt. I can buy four calipers for my F 350 for the price of a front caliper on this bike.

[Poldark]

22 hours ago, Swiss Toni said:

Take your grease gun nozzle off the gun. Screw the hose gently into the caliper. Pump! 99.99% of pistons will come out. No fuss!

That's the way it's done at my local bike shop.  It works great for getting the piston out, but leaves a mess of grease to clean up.

10 hours ago, RickLee said:

When you get a load of the price of NEW calipers.... wow.  Are there any reasonably priced aftermarket calipers for 1980 GS1000?

I'm not aware of any direct aftermarket replacements.  Rebuild kits are the normal way of dealing with motorcycle brake calipers.  Sometime a good cleaning is enough.  If you're looking at doing an upgrade; with a little work, a latter model multi-piston caliper can be fitted.  Re-engineering is the essence of OSS.

1 hour ago, Apples said:

Not that I have seen. These are getting rebuilt. I can buy four calipers for my F 350 for the price of a front caliper on this bike.

All my trucks have been Ford F-series, but compare the production numbers to our vintage Suzukis, there's no comparison. 

[Chrisr]

Hi saw this discussion going on and wondered is there any direct bolt on calipers for early gs1000 can lay my hands on some early slabside twin pots but they normally grab onto floating disc ???

[BigT]

No direct bolt ons

Late 80/90s Tokikos are the go to, with an adapter plate

 

https://www.thegsresources.com/_forum/showthread.php?222549-Twinpot-Brake-Upgrade-on-GS1100E-GS750E-GS750ES-GS1000G-GS1000E-GS850G