[Jimijet]

imported post

When I tore this stuck rear brake apart It had a third brake plate without the lining, being used as some kind of shim I guess so the piston won't have to come out as far. I removed that and rebuilt both caliper and master cyl. with all new parts. I cannot get the pedal to not want to bottom out on the frame when you hit it hard. The bike will stop but I don't like the pedal travel. I have powerbled , forward and backward bled. There is no air in the system. I have adjusted out the rod as far as it will go on the piston. Still it feels mushy and alot of travel Help Jim

 

[RedWinger]

imported post

 

[edzinohio]

imported post

If this is an 82, the foot pedal may not be linked to the front. I think that may have been an 83 thing. Not sure about that though.

 

[rcmatt007]

imported post

welcome to the forum Jim... if it is later than 79 has to be a 1100 not a 1000... maybe the actual brake cylynder (okay I cannot spell, but you should see my penmanship) needs to be honed.... there might be something catching there...

I guess not many places do that nowadays...but we older folks remember honing brake cylinders (darn still worng):1000darkblue::12red:

 

[RedWinger]

imported post

 

[CRAIGA]

imported post

Hey i think your right i have a 1982 GL1100- rear brake pedal only operates the rear brake- not the front-=o by the way-that may have been a brake pad shim on the brake pad- this will affect brake pedal travel- Rec. to re-install pad shim-or if shim in poor shape-rusted-replace with new

CRAIGA

 

[edzinohio]

imported post

I am wondering if your brake lines have too much flex in them.

Are the brake pads able to make contact with the rotor and release? Is it mainly a squishy brake pedal?

Are you sure your master cylinder is ok?

 

[exavid]

imported post

Jimijet wrote:

When I tore this stuck rear brake apart It had a third brake plate without the lining, being used as some kind of shim I guess so the piston won't have to come out as far. I removed that and rebuilt both caliper and master cyl. with all new parts. I cannot get the pedal to not want to bottom out on the frame when you hit it hard. The bike will stop but I don't like the pedal travel. I have powerbled , forward and backward bled. There is no air in the system. I have adjusted out the rod as far as it will go on the piston. Still it feels mushy and alot of travel Help Jim

Only two possibilities I can see. First is that there is still some air in the system, was the brake pedal firm before you rebuilt the caliper? If it was there's still some air in the system. Possibly at the upper banjo bolt or the lower one. Wouldn't hurt to bleed it again. The other possibility is a worn out master cylinder.

I suspect air in the system since you've had to crank the rod all the way out and it wasn't before. Mushy and lots of travel is just about always air in a disk brake system, unless as the guys are suggesting you have a soft brake line, but there isn't all that much rubber in the rear brake.

 

[Jimijet]

imported post

the brake is rear only dual started later

 

[Jimijet]

imported post

Sorry I miss hit the year It is a 82 1100 with rear only. I have cleaned out the master cylinder hit it easy with a small hone and used a bore gage on the cylinder. As far as specs go it is within the upper end of being allright plus i thought that I would see fluid leaking back past the piston if it was not to spec. I was leaning on the hose idea but I always thought that the hose being bad would make the brakes stick and not pull back. As far as the plate, it looks as if it might of had a bonded pad on it and they removed it and just used it for a shim. All microfiches doesn't show any plates of this thickness as a shim.also craga does you bike have this shim? Reply also to the brakes are locking up fine on the rotor and releasing. If you push the lever down slow with your hand it is so so but to ride it and push down fast with your foot it hits the frame but still stops the bike but not to my satisfaction

 

[Retro48]

imported post

I just did the brakes on my '83. It is the one with the rear and right front brakes are operated by the foot brake. Just a guess but sounds like the foot brake master cylinder is by-passing. Have you rebuilt the master cylinder?

 

[Silicon Sam]

imported post

The GL1100 brakes are confusing....

'80 and '81 single piston calipers, front and rear separate
'82 dual piston calipers, front and rear separate
'83 dual piston calipers, linked rear and right front

Another difference, the '83 front calipers have different sized pistons, the '82 should have the pistons the same size. Can anyone verify the '82 caliper pistons being the same on both sides?

Raymond

 

[FitzAl]

imported post

None of teh gl1100 pads had shims Jimijet. It seems that a previous owner must have had the same problem as you and put the shim in to limit the pedal travel. When you open the bleed nipple and hit the pedal, does the brake fluid squirt out in a nice strong spurt, or do you get a small spurt or dribble? If it's not a strong spurt then the master cylinder isn't doing the job right.

 

[twisty]

imported post

Jimijet wrote:

Sorry I miss hit the year It is a 82 1100 with rear only. I have cleaned out the master cylinder hit it easy with a small hone and used a bore gage on the cylinder. As far as specs go it is within the upper end of being allright plus i thought that I would see fluid leaking back past the piston if it was not to spec. I was leaning on the hose idea but I always thought that the hose being bad would make the brakes stick and not pull back. As far as the plate, it looks as if it might of had a bonded pad on it and they removed it and just used it for a shim. All microfiches doesn't show any plates of this thickness as a shim.also craga does you bike have this shim? Reply also to the brakes are locking up fine on the rotor and releasing. If you push the lever down slow with your hand it is so so but to ride it and push down fast with your foot it hits the frame but still stops the bike but not to my satisfaction

Jimijet, a few things come to mind on your rear brake problem.

-Check you rear wheel & wheel bearings for any movement or play. If that rear wheel is moving around it could be kicking the brake pads back in enough to cause a long pedal travel.

-Make sure the rear caliper is free to slide on it's mounting pins. If the caliper is frozen on the pins it can't move& will cause a low pedal.

-Measure the rotor thickness, maybe it is worn thin or has been turned too thin. A thin rotor would explain that added shim.

Twisty

 

[jackjohn]

imported post

I would lean toward air in the system or possibly a damaged master cylinder. It has been a while since I rebuilt the calipers on mine but I don't remember having nearly enough available space (with new brake pads) for a brake pad backing plate to be used as a shim. If there is that much space, the disk would have to be worn dangerously thin or something is bent.

Jack

1982 GL1100I OE

 

[exavid]

imported post

The way to test the master cylinder is to plug it's outlet and see if the pedal is solid. I believe the previous owner had a frozen caliper and put the shim in on the side where the pad wasn't wearing. That way you could compensate for the uneven wear, probably didn't realize the caliper wasn't moving. It doesn't make any difference on master cylinder stroke, it always takes the same amount of fluid out of the master cylinder to operate the brakes because the pistons don't retract after they operate, they just release the pressure on the disk. With drum brakes wear on the shoes requires more fluid to be pumped out of the master cylinder since they retract and push the fluid back to the master, that's why you have to adjust (or have automatic adjusters as modern cars do) drum type brakes while disk brakes require no adjustment. As the pads in a disk system wear you do have more fluid in the system, but the amount the master has to pump stays the same. If you had a leakless disk brake system you could actually measure the thickness of the pads by the amount the fluid goes down in the reservoir.

 

[Jimijet]

imported post

Thanks for all the info. I have actually done all of it 2 times and gone thru a quart of dot 3. I think I have to go the hose route since everything else has been done. Great site for help. Sorry for the triple posting. I didn't think It went thru. Will post up next week I hope with better results :gunhead:

 

[GWNorman]

imported post

Let us know how you get on with the task Jimijet. The extra shim is very suspicious and leads me to suspect teh master cylinder is not the best.

 

[exavid]

imported post

Silicon Sam wrote:

The GL1100 brakes are confusing....

'80 and '81 single piston calipers, front and rear separate
'82 dual piston calipers, front and rear separate
'83 dual piston calipers, linked rear and right front

Another difference, the '83 front calipers have different sized pistons, the '82 should have the pistons the same size. Can anyone verify the '82 caliper pistons being the same on both sides?

Raymond

I believe they changed the piston sizes in the front calipers when they went to linked brakes. The smaller pistons on the left, linked caliper reduces the possibility of front wheel lockup when hitting the rear brake pedal.

 

[exavid]

imported post

Jimijet wrote:

Thanks for all the info. I have actually done all of it 2 times and gone thru a quart of dot 3.

Honda calls for DOT4for the 1500 and I think for the 1200. Does the 1000 require DOT3? I don't remember when DOT4 came out.