GL1800Riders Forums banner
1 - 20 of 22 Posts

·
Registered
Joined
·
2,162 Posts
Discussion Starter · #1 ·
Was going to go to Oshkosh this AM. I had just reinstalled the front wheel after getting a new tire. I noticed right away that hand brake free play was very little. I drove a couple miles and noticed the motor was laboring. I stopped for a minute and then was able to continue. I decided to go right back home. Had to stop again for a minute before I could continue. The only thing I can think of that would cause this is that when I pushed the brake pads back to reinstall the front wheel I loosened up a piece of crud that had been somewhere out of the way til then. When I got home I checked and both front discs and the rear one were hot. I did a brake flush of the entire system, hand brake and foot brake and now it seems OK but I don't have time to go for a test ride as I have another appointment. After flushing the foot brake system the hand brake free play was still very little so I flushed the front too.
Does this sound like something that would be caused by the brake recall issue?
 

·
Registered
Joined
·
3,610 Posts
Reason for recall:
There is a small valve in the secondary master cylinder that must allow fluid to flow back and for pressure to equalize after applying brakes. If it does not allow fluid to backflow, the rear brake will drag and overheat. The problem is caused by going too long......or never bleeding and replacing brake fluid.


It sounds like you may have overfilled the fluid reservoirs. When fluid gets hot and expands and the reservoir is overfilled, the brakes will drag.


Think back to when you pushed the pistons back in when you installed the front wheel.


gramps


.
 

·
Premium Member
Joined
·
31,972 Posts
Reason for recall:
There is a small valve in the secondary master cylinder that must allow fluid to flow back and for pressure to equalize after applying brakes. If it does not allow fluid to backflow, the rear brake will drag and overheat. The problem is caused by going too long......or never bleeding and replacing brake fluid.


It sounds like you may have overfilled the fluid reservoirs. When fluid gets hot and expands and the reservoir is overfilled, the brakes will drag.


Think back to when you pushed the pistons back in when you installed the front wheel.


gramps


.


Makes perfect sense to me , thanks gramps .hopefully his is all it is
 

·
Registered
Joined
·
2,162 Posts
Discussion Starter · #4 ·
Reason for recall:
There is a small valve in the secondary master cylinder that must allow fluid to flow back and for pressure to equalize after applying brakes. If it does not allow fluid to backflow, the rear brake will drag and overheat. The problem is caused by going too long......or never bleeding and replacing brake fluid.

The front discs were hot too???

It sounds like you may have overfilled the fluid reservoirs. When fluid gets hot and expands and the reservoir is overfilled, the brakes will drag.


Think back to when you pushed the pistons back in when you installed the front wheel.


gramps


.
I didn't add any fluid and after installing the front wheel I pumped the brakes back up so the fluid would have returned to what it was before I took the wheel off.
 

·
Premium Member
Joined
·
31,972 Posts
I didn't add any fluid and after installing the front wheel I pumped the brakes back up so the fluid would have returned to what it was before I took the wheel off.
Bummer , I would pull wheel off again and look real close at brake pads . Maybe something is misaligned or something . Gotta be something simple .
 

·
Registered
Joined
·
3,610 Posts
I didn't add any fluid and after installing the front wheel I pumped the brakes back up so the fluid would have returned to what it was before I took the wheel off.

In that case I would put the bike on the center stand, somehow raise the front so that the front wheel is free to spin, and then check to see if a brake shoe is dragging....especially on the left rotor.


If the left rotor is being dragged, the caliper will move slightly upward and the linkage that activates the anti dive valve AND the rear brake will rotate a very small amount. That would explain why the rear brake also got hot.


The recall replaces the secondary master cylinder at the left caliper AND the rear brake master cylinder (behind the oil fill opening).


Like Rail said, "it's gotta be something simple".


good luck :smile2:


gramps


.
 

·
Registered
Joined
·
2,162 Posts
Discussion Starter · #8 ·
In that case I would put the bike on the center stand, somehow raise the front so that the front wheel is free to spin, and then check to see if a brake shoe is dragging....especially on the left rotor.


If the left rotor is being dragged, the caliper will move slightly upward and the linkage that activates the anti dive valve AND the rear brake will rotate a very small amount. That would explain why the rear brake also got hot.


The recall replaces the secondary master cylinder at the left caliper AND the rear brake master cylinder (behind the oil fill opening).


Like Rail said, "it's gotta be something simple".


good luck :smile2:


gramps


.
Would disabling the antidive solve this problem?
 

·
Premium Member
Joined
·
31,972 Posts
Would disabling the antidive solve this problem?
Yes onnthe rear brake it will. Take a grinder after nub on anti dive after you take 2 bolts off . Skip the silly nickel or shim trick . I have never had the anti dive operable on either of my 1800's . Horrible designed system in my mind .
 

·
Registered
Joined
·
3,610 Posts
Would disabling the antidive solve this problem?

The "problem" appears to be something that is is preventing the brake pads from seating properly and needs to be corrected.


Disabeling the anti dive valve will have no effect on the rear brake being activated when the front brake is squeezed.


Take a look at the hinge point on the left side just behind the axle. Then note that there is a rod leading into the secondary master cylinder and a brake hose leads from it down to where the anti dive valve lives.


When the front brake is applied, the caliper rotates on the hinge and pushes the rod into the secondary master cylinder, which in turn releases some brake fluid to the hose leading to the anti dive valve, which in turn activates the rear brake a small amount.


good luck :smile2:


gramps


.
 

·
Premium Member
Joined
·
31,972 Posts
The "problem" appears to be something that is is preventing the brake pads from seating properly and needs to be corrected.


Disabeling the anti dive valve will have no effect on the rear brake being activated when the front brake is squeezed.


Take a look at the hinge point on the left side just behind the axle. Then note that there is a rod leading into the secondary master cylinder and a brake hose leads from it down to where the anti dive valve lives.


When the front brake is applied, the caliper rotates on the hinge and pushes the rod into the secondary master cylinder, which in turn releases some brake fluid to the hose leading to the anti dive valve, which in turn activates the rear brake a small amount.


good luck :smile2:


gramps


.
Very,very good explanation . I would still loose the silly anti dive nonsense . Could be as simple as a rock behind brake pad tab Ken .
 

·
Premium Member
Joined
·
5,625 Posts
JD, if it were me, I would be retracing the work I just did since that is when the problem showed up.

Check the front brake pads to be sure the top of all 4 brake pads are properly seated in the retaining clips. Check clearance of left rotor to caliper and fork alignment. I suspect you will find something amiss.

That said, in my feeble mind, the SMC would not likely be the issue here. Only a master cylinder could apply front AND rear brakes. If everything touched in the wheel change looks good, go to the foot brake and confirm operation and lever including full return when released. Same for hand lever confirming the little plunger pin is properly seated in the lever and returning.

Let us know what you find.




Sent from my iPad using Tapatalk
 

·
Banned
Joined
·
683 Posts
The secondary master is on the left fork tube - it does not have a valve specific for release of fluid but the plunger piston does have to fully extend in order to open the intake port and allow the brake fluid pressure to neutralize. It is basically a duplicate of any other brake master just uses the disk and caliper rotation to activate. What probably happened is the left caliper is hanging up and not able to pivot which in turn will disallow the piston to retract. check to see if it's binding. Push the left caliper down, if it move and the lever release pressure than that is the issue.

Also bleeding the brakes and flushing will not fix this issue if the caliper is binding so check this first. The recall is meant to address the secondary hang issue and in general only normal fluid changes are required.
 

·
Premium Member
Joined
·
5,625 Posts
triplay I do not disagree with your description of the operation of the SMC.

However, the OP said all three rotors were hot, indicating brakes dragging all the way around. An internal issue in the SMC will only act on the rear brakes. An issue at the left caliper could drag that rotor and, via (proper) activation of the SMC, hang the rear as well. I do not believe that either of those problems would affect the right front brake. Just my WAG.


Sent from my iPad using Tapatalk
 

·
Banned
Joined
·
683 Posts
Good point raised however the system pressure will be raised in general although the rear will show the most drag. all three will exhibit drag as the entire system will be in a fluid lock situation. Again if the caliper is pushed down and pressure released then the problem is found and one may move on towards a reliable solution other than bleeding the brakes to death :)
 

·
Registered
Joined
·
3,834 Posts
Had you added fluid at any time before you changed the pads?
Is it possible that after you replaced the worn brake pads, with brand new pads that the thickness of the new pads caused you to have too much fluid in the system?
Once you flushed the system, you were back to the proper fluid level, so no more problem.
 

·
Registered
Joined
·
2,162 Posts
Discussion Starter · #17 ·
Had you added fluid at any time before you changed the pads?
Is it possible that after you replaced the worn brake pads, with brand new pads that the thickness of the new pads caused you to have too much fluid in the system?
Once you flushed the system, you were back to the proper fluid level, so no more problem.
I didn't replace the pads. Just pushed them back when I reinstalled the wheel after a front tire change.
I checked the left caliper and it was free. I disabled the antidive and rode to RTE and back with no problem.
Thanks everyone for the input.
 

·
Registered
Joined
·
694 Posts
Just wonder JD was there any noise from this like a rubbing noise?
 
1 - 20 of 22 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top