Rear brake caliper play? - Suzuki GSXS1000 Forum
User Tag List

 3Likes
  • 2 Post By USSENTERNCC1701E
  • 1 Post By JohnCW
 
LinkBack Thread Tools
Old 09-18-2017, 04:30 AM Thread Starter
Junior Member
 
Join Date: Jul 2017
Posts: 4
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
(Thread Starter)
Rear brake caliper play?

Quick question, I've some play in my gsxs1000 rear brake caliper, I can move it with my hand a few mm back and forth. Is this normal?

I'll grab a video later today if it's not.
slinky2000 is offline  
Old 09-18-2017, 08:48 AM
Senior Member
 
Join Date: Feb 2017
Location: Mooresville, NC
Posts: 418
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 177 Post(s)
Which direction? If you move the caliper inline with the tires and have play the caliper is loose and needs to be tightened. If you move the caliper inline with the caliper piston and you have play, pump the rear brake and see if it goes away. If it doesn't the caliper piston maybe seized in the bore or you have no line pressure.
Supercharger is offline  
Old 09-18-2017, 01:24 PM
Senior Member
 
USSENTERNCC1701E's Avatar
 
Join Date: Apr 2016
Location: Utah, USA
Posts: 529
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 164 Post(s)
Garage
There actually is a little bit of play in basically all disc brake calipers. It can be a little disconcerting the first time you notice it, but if you take a close look, you can see they're designed that way. Basically there's a rubber bushing/sleeve around the mount bolts and through caliper, after a long time, this can wear out, but a couple years is unlikely. I don't know for certain why, but I assume since it's such a ubiquitous design, there's a pretty good reason. Maybe that play reduces the likelihood of lock-ups?

I'll post a video of mine in a few minutes.

Edit: our front brakes are a notable exception to that.

2016 GSXS1000FAL6

Last edited by USSENTERNCC1701E; 09-18-2017 at 01:33 PM.
USSENTERNCC1701E is offline  
 
Old 09-18-2017, 01:51 PM
Senior Member
 
USSENTERNCC1701E's Avatar
 
Join Date: Apr 2016
Location: Utah, USA
Posts: 529
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 164 Post(s)
Garage
https://youtu.be/knWDhqf8aJw
Kassu and slinky2000 like this.

2016 GSXS1000FAL6
USSENTERNCC1701E is offline  
Old 09-18-2017, 09:36 PM
Member
 
Join Date: May 2017
Posts: 43
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 14 Post(s)
I don't own a GSX-S1000 so please take that into consideration regarding my response ........

If you can 'shake' a caliper it generally indicates the pads are being pushed or pulled clear of the rotor. Motorcycle disk brakes are supposed to have the pads sitting with just the lightest touch again the rotors . Even though there is clearance in the guide pins (deliberately to allow the caliper to self align to the rotor), you generally can't rattle the caliper on the guide pins because the pads are being held flush against the rotors by the pistons. When people complain of excessive pedal/lever travel that the first thing I tell them to check (does the caliper rattle around on the guide pins).

It's generally caused by dry dust seals and gunned up pistons acting like return springs and excessively retracting the piston/pads away from the rotor. A warped rotor would be another cause. The main problem people notice is excessive pedal/lever travel. It's more common on the rear caliper because it cops the water and road crap from both wheels.

Easy to test if it's a warped rotor or sticky seals. With the bike stationary just press the brake pedal (and the caliper will solidly clamped to the rotor). Release the pedal, and if the caliper is now 'shaky' loose then clearly the pistons and pads have retracted clear of the rotor. There is generally only one thing causing that, dry sticky dust seals gripping the piston (instead of the piston sliding through the dust seal) making it act like a strong rubber return spring.

Overhauled calipers with nice polished pistons, and pistons and seals lubricated with a suitable silicon rubber safe grease do not act like return springs. They allow the pads to remain against the rotor when the brakes are released, so the caliper can't be 'jiggled'. I overhaul the calipers on my bike every-time I change pads. Takes a whole additional 30 minutes, tops.

P.S. Don't use brake fluid to lubricate caliper seals. It's water soluble and will completely wash away in the first decent downpour. Only ever use a suitable rubber safe silicone grease. If unsure what brand to use, just buy a small pack of the excessively priced stuff supplied by Ohlins so you know it is correct.
USSENTERNCC1701E likes this.

Last edited by JohnCW; 09-18-2017 at 09:41 PM.
JohnCW is offline  
Old 09-18-2017, 09:46 PM
Senior Member
 
USSENTERNCC1701E's Avatar
 
Join Date: Apr 2016
Location: Utah, USA
Posts: 529
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 164 Post(s)
Garage
^^^ good to know, thank you.

I actually do need to bleed my rear. And usually when I've got my hands on calipers it's because I'm replacing the pads, so would be after reinstall but before repressurizing.

2016 GSXS1000FAL6
USSENTERNCC1701E is offline  
Old 09-18-2017, 10:36 PM
Member
 
Join Date: May 2017
Posts: 43
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 14 Post(s)
Quote:
Originally Posted by USSENTERNCC1701E View Post
^^^ good to know, thank you.

I actually do need to bleed my rear. And usually when I've got my hands on calipers it's because I'm replacing the pads, so would be after reinstall but before repressurizing.
And that's exactly what is generally happening. The caliper flops all over the place when you replace the pads because you've pushed the pistons back. So the whole assembly just flops around on the loose guide pins. But push pads of 4"? long and 2"? wide neatly against each side of the rigid rotor, and it should be quite rigid to a light 'jiggle' test. Give it a violent shake will naturally push the pistons in and the whole thing become sloppy again.

Usually a rear brake with this problem can go somewhat unnoticed because the pedal has a lot of travel. However you'll soon have a problem on a front brake with this issue if you only use a couple fingers on the brake lever. The excessive travel to first push the pistons back to be neat against the rotors causes the lever to end up squashing into the other fingers rapped around the throttle.

You'll often see people on forums with this problem trying to adjust levers, fit different levers, new brake lines, replacing master cylinders etc ..... when it was all due to the so easily fixed sticky caliper seals/pistons. The proven method of getting a piston out of a caliper is to use compressed air to blow it out. Can take every bit of 120psi to pop a cruddy piston out of a bone dry seal, and then it will came out with a rifle crack 'bang' (shatter your fingers is someone was silly enough to have them in the way). That stubbornness of the piston to move was massive lost braking efficiency when the brakes were in operation. That why I always dismantle, polish the pistons, fit new seals and fully lubricate the calipers with every brake pad change. The difference it makes in terms of pedal/lever travel distance, braking effort, and linear response is VERY noticeable.

Last edited by JohnCW; 09-19-2017 at 02:21 AM.
JohnCW is offline  
Old 09-19-2017, 11:27 AM Thread Starter
Junior Member
 
Join Date: Jul 2017
Posts: 4
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
(Thread Starter)
Quote:
Originally Posted by USSENTERNCC1701E View Post
Perfect, that's exactly how mine behave!
slinky2000 is offline  
Old 09-21-2017, 12:43 AM
Member
 
Join Date: May 2017
Posts: 43
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 14 Post(s)
Quote:
Originally Posted by slinky2000 View Post
Perfect, that's exactly how mine behave!
Which isn't consistent with how a new bike is. I was in the dealers today so checked one out. Just the very slightest barely perceptible movement, consistent with every other bike I've owned.
JohnCW is offline  
Old 10-14-2017, 06:44 AM
Junior Member
 
Join Date: Mar 2017
Posts: 7
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 1 Post(s)
Quote:
Originally Posted by JohnCW View Post
And that's exactly what is generally happening. The caliper flops all over the place when you replace the pads because you've pushed the pistons back. So the whole assembly just flops around on the loose guide pins. But push pads of 4"? long and 2"? wide neatly against each side of the rigid rotor, and it should be quite rigid to a light 'jiggle' test. Give it a violent shake will naturally push the pistons in and the whole thing become sloppy again.

Usually a rear brake with this problem can go somewhat unnoticed because the pedal has a lot of travel. However you'll soon have a problem on a front brake with this issue if you only use a couple fingers on the brake lever. The excessive travel to first push the pistons back to be neat against the rotors causes the lever to end up squashing into the other fingers rapped around the throttle.

You'll often see people on forums with this problem trying to adjust levers, fit different levers, new brake lines, replacing master cylinders etc ..... when it was all due to the so easily fixed sticky caliper seals/pistons. The proven method of getting a piston out of a caliper is to use compressed air to blow it out. Can take every bit of 120psi to pop a cruddy piston out of a bone dry seal, and then it will came out with a rifle crack 'bang' (shatter your fingers is someone was silly enough to have them in the way). That stubbornness of the piston to move was massive lost braking efficiency when the brakes were in operation. That why I always dismantle, polish the pistons, fit new seals and fully lubricate the calipers with every brake pad change. The difference it makes in terms of pedal/lever travel distance, braking effort, and linear response is VERY noticeable.
thank you bro!
so i should clean the caliper and pistons once a year?

GSX-S1000A 2016
bigbigriver is offline  
 

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Suzuki GSXS1000 Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in









Thread Tools



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome