Rear Brake Caliper - Rookie needs help

[northwestparider]

I'm really felling like a rookie tonight. I work on my cars and previous motorcycles. I took a 68 Chrysler that hadn't been on the road for 35 years and restored it to driver condition, but I'm stumped. Most likely missing something real simple. I saw somewhere that recommended removing the muffler - it's off and out of the way.

I bought some OEM pads and wanted to put them in tonight. I figured I would start with the rear ones. I want to clean the caliper and polish the pistons up good before installing the new pads. I cannot seem to get the caliper off. The manual shows replacing the pads with the caliper in place - that's a first for me. I removed two bolts from the front side of the caliper; one that seems to hold the caliper bracket to the swing arm and the other seems to hold the front of the caliper to the bracket. There is a pin in the bracket that it seems the caliper slides on and should off to the outside of the bike. Additionally from looking at the manual the bottom backside of the caliper bracket is mounted by the rear axle.

It seems to me that if I pull the rear wheel I'll be able to remove both the caliper bracket and the caliper. Or I could put the front bolt that hold the caliper to the swing arm back in and just pull the caliper.

Does any of this sound correct? I'm probably making this harder than it needs to be.

I looked at numerous videos on Youtube and multiple threads here. Heck the one guy on Youtube even said Larry ( @Igofar ) is probably laughing at him. I never saw a video where he go this brakes back on.

Thanks

 

[Igofar]

Sent you a message, we can talk tomorrow

 

[docw1]

I'm sure others will respond here, and I'm certainly no master mechanic, but in my experience, you can change the pads without removing the calipers, but you'll have to push in the dirty pistons to do so. If you want to clean the pistons, as many suggest, then to remove the calipers, you have to remove the rear wheel. and the caliper stopper bolt. I see Larry has responded. He will take you through the whole process to make sure it's done correctly. Listen to him.

 

[northwestparider]

I meant to post this picture so that you folks would know what boys I took out.

 

[jfheath]

Just for information.

The torque setting on the above diagram from the manual is drastically wrong. The red arrow on the right hand side is pointing to the slider pin that is mounted on the caliper at the forward end. If you tighten that pin to 69Nm, you will need a new pin and something to repair the stripped out threads. The actual torque for that pin is 27Nm. Look up the torque in the table at the front if the chapter, and again in the general information - but better still, don't remove it at all. There is usually no need unless it needs to be replced.

The 69Nm is the torque for the caliper bracket stopper bolt, which isn't shown in this diagram.

The diagram is a tad confusing as to what fits where. Here is a colour coded version. The red bits fit together, the green bits fit together. Note that the green bolt does not fit through the red hole partly obscured at the bottom of the caliper.

 

[STRider]

Here, let me try!

The caliper can't be removed from the bracket while the axle and wheel are still in place. Though removing the green bolt/pin in John's post will release the forward end of the caliper (forward - toward the bike's front) it will still be held in place by the red pin. To get it off you'd have to slide the caliper away from the centerline of the bike, but with the wheel in place the caliper is still straddling the disc and can't slide in that direction enough to release from the bracket. You might think then that you could rotate the caliper clockwise about the red pin to clear the disc, but certainly not with the brake hoses still attached. Trust me, don't bother.

Having just done this same service a couple months ago, you CAN replace the pads without removing the caliper but that will require compressing the pistons to provide enough clearance for the new pads which are thicker than the used ones. That only requires removing the pad retention pin which is the rightmost part in John's diagram

But you really can't service the pistons without removing the caliper and bracket which does require removing the wheel and axle.

 

[Kevcules]

Just for information.

The torque setting on the above diagram from the manual is drastically wrong. The red arrow on the right hand side is pointing to the slider pin that is mounted on the caliper at the forward end. If you tighten that pin to 69Nm, you will need a new pin and something to repair the stripped out threads. The actual torque for that pin is 27Nm. Look up the torque in the table at the front if the chapter, and again in the general information - but better still, don't remove it at all. There is usually no need unless it needs to be replced.

The 69Nm is the torque for the caliper bracket stopper bolt, which isn't shown in this diagram.

The diagram is a tad confusing as to what fits where. Here is a colour coded version. The red bits fit together, the green bits fit together. Note that the green bolt does not fit through the red hole partly obscured at the bottom of the caliper.

I don't see anything wrong with the op's diagram. The stopper bolt is the one he's pointing to and the torque setting is what it's supposed to be?

Remove your rear wheel to easily access the caliper to slide it off it's mount. Pads can be changed with the caliper still in place, but not recommended. You want to be able to clean the area and pistons real well before they get compressed to make room for new pads. Check that the spring clips are still in good condition and positioned properly. Re assemble and enjoy.
No need to bleed the fluid for pad replacement but maybe check the fluid level to make sure it's correct after you push fluid back to the reservoir.(remove reservoir cover while doing this and use a towel on your tank to prevent fluid dripping down on the paint) Bleeding brake fluid yearly on these bikes is recommended. That's quite a process too.

 

[SMSW]

No need to bleed the fluid for pad replacement... Bleeding brake fluid yearly on these bikes is recommended. That's quite a process too.

No need to bleed, but given how sensitive the SMC is to crud, and its cost, it is good preventative maintenance to do this at least every 2 yrs as Honda suggests or yearly as many guys do. How often do you go in there and change the pads, clean stuff up, etc? If not yearly, then flush the system when you do the pads.

 

[northwestparider]

Thanks everyone for chiming in. I had a good conversation with IGOFAR tonight and I've to collect some parts before much else can be done.

I don't see anything wrong with the op's diagram. The stopper bolt is the one he's pointing to and the torque setting is what it's supposed to be?

Remove your rear wheel to easily access the caliper to slide it off it's mount. Pads can be changed with the caliper still in place, but not recommended. You want to be able to clean the area and pistons real well before they get compressed to make room for new pads. Check that the spring clips are still in good condition and positioned properly. Re assemble and enjoy.
No need to bleed the fluid for pad replacement but maybe check the fluid level to make sure it's correct after you push fluid back to the reservoir.(remove reservoir cover while doing this and use a towel on your tank to prevent fluid dripping down on the paint) Bleeding brake fluid yearly on these bikes is recommended. That's quite a process too.

I was actually trying to point at both the Stopper Bolt and the slider. That diagram is a bit confusing.

 

[Igofar]

I don't see anything wrong with the op's diagram. The stopper bolt is the one he's pointing to and the torque setting is what it's supposed to be?

Remove your rear wheel to easily access the caliper to slide it off it's mount. Pads can be changed with the caliper still in place, but not recommended. You want to be able to clean the area and pistons real well before they get compressed to make room for new pads. Check that the spring clips are still in good condition and positioned properly. Re assemble and enjoy.
No need to bleed the fluid for pad replacement but maybe check the fluid level to make sure it's correct after you push fluid back to the reservoir.(remove reservoir cover while doing this and use a towel on your tank to prevent fluid dripping down on the paint) Bleeding brake fluid yearly on these bikes is recommended. That's quite a process too.

Perhaps you should look at that a second time, as the stopper plug is not even shown or listed on that diagram.
The torque setting your stating as correct, is also the wrong torque for that fastener.
The red arrow is pointing to the caliper assembly bolt, and as John pointed out, the manual has the wrong torque value, and if used, that will damage the rear caliper.

 

[TerryS]

My advice (hard won, and a little expensive) is that re-fitting the calliper slide pin with the calliper in place is a Bad Idea. I foolishly removed mine, cleaned and lubed it, and then refitted it and tightened it up. I somehow cross-threaded the slide pin so that it was no longer perfectly parallel to the pin located on the mounting bracket. The end result was that as I tightened the pin, it pulled the back brake pad hard onto the disc. I had to buy a secondhand calliper to fix my cock-up.

Refitting the slide pin to the loose calliper by hand shouldn't cause the same issue, but go easy and go straight.

As others have said, the correct way to remove the calliper is to loosen the mufflers and swing them out of the way, retract the axle bolt, and then the calliper and mount bracket will swing up out of the gap (with the wheel still in place on the drive splines). then you can slip the calliper off the mount bracket leaving both the sliding pins in place.