2000 Non-ABS ST1100 Caliper Overhaul

[STutter]

Hi all, I tried searching but couldn't come up with any answers for this one...

The brakes on my ST1100 have recently made a bit of a crunch/groan when the lever has pressure on it. I also find that when moving the bike out in the morning, theres a metallic hiss where the front pads are touching the rotor.

After doing a bit of research I believe the pistons in the calipers are probably gummed up and need some cleaning and new seals. I bought some new EBC pads today from Rising Sun Honda, and they cost $150 (which I thought was a bit exxy, but I need the pads sooner than later). I also picked up a oil filter for.... $23. This is why I don't buy stuff locally unless I'm in a hurry

I thought I'd start with the rear and see how I went (never having disassembled a caliper before). I didnt realise the whole thing was SO DIRTY.



Anyway after some stuffing about I managed to pop out a piston with my little air compressor. I'd read only to use fingernails or wooden scrapers to remove the gunk so thats what I did. I couldn't get rid of this stuff though, and I think I might be pitting...



If it IS pitted, then that means a new piston, doesn't it? Can I get by without buying one immediately and just trying this one out with the new seals?

Also, now that one has popped out... how do I get the other one out? 

I worry that this has taken me half a day and I still have the front to do as well as an oil change!

[Brock]

Put the cleaned up one back in, limt its travel with a clamp and carefully pop the other one out. Oil change is easy, just remove the bolts in the lower left grey panel, and you should have enough room to get the filter off by hand. Unless its been over tightened on the last change. For future reference, the Repco ROF 135 oil filter fits, and only costs about $7.00

[STutter]

Thanks Brock, I couldnt get the other one out via air, heat or wiggling, so I hooked it back up to the brake line and got it out that way. Now to replace the pads, hook it all back up and bleed.


Then onto the fronts 

[Brock]

Make sure the pistons are pushed right in, its easier to get the caliper full of oil and most of the air out. It can be a pain getting the last bubble or two out.

[saaz]

Giving the pistons a good clean before forcing them back in to fit new pads should reduce the need to do a full overhaul, or at least less often.

[STutter]

OK so I've gotten the rear caliper back on. Everything seems to be behaving.

When rotating the wheel, it seems a little "heavy". When the brakes are on, it stops. When the brakes are off, it rotates OK. There is no hiss or anything sounding like pad contact.

I've never really bothered rotating the rear before, is this heavyness just related to shaft drive instead of chain (which Im more familiar with)?

Going to start on the fronts. Tried taking off the front fender for ease of access and the two allen bolts are fine, but the two philips-head bolts are on mighty tight

[STutter]

OK cleaned up the fronts. Had one very sticky piston on the right.

Have gone to put back the LHS caliper on but it seems there is a tiny bit of movement (less than 1mm side to side). I'm guessing this might stiffen up once the brakes are full and back to fully functioning. There are only two bolts holding the caliper on, and both of them are on tight. Couldn't see any washers missing or anything. Odd.

Anyway, the RHS one should be done this arv, then put all back together with a whole heap of bleeding and test ride tomorrow morning around the block. The RHS caliper also had some jelly/gunk behind the caliper which is crazy. Looks like the previous owner stripped the calipers back to bare metal and then painted a light coat of red, then over again with black 

This bike is like an archaeology dig. Fingers crossed it all works first time and I havent forgotten anything.

[Brock]

There is built in side play, to allow the calliper to centre on the brake disc, and to take up as the pads wear.

[STutter]

Thanks Brock. Thats a load off my mind 

[saaz]

There should be some high temp grease on the sliding pins so they more freely, as there should be some movement. The grease also means the pads are less likely to drag.  Perhaps the previous owner put some anti squeal grease/compund behind the brake pad?  Never found the need on the ST11 myself.

[STutter]

Well that completes todays effort.

Discovered the clutch master cylinder was almost dry. Fixed that and bled. Much more responsive now.

Shot a piston out with compressed air. I know it happens but it missed the cushion of rags set up to catch it  They come out at a rate of knots, no? Pretty dramatic!

Anyway, put all cleaned pistons back in, cleaned calipers and pads, bled the system etc. I just set up a one-man bleeding kit on the RHS and pumped until all the bubbles disappeared. Hooked up to LHS and did a couple of pumps - no bubbles. I hope this is the correct way to do it.

Went for a gallop around the back yard, but noticed the WORST noise coming from the RHS caliper. Sounded like metal scratching/pinging against metal. Makes the noise all the time, even just moving the bike backwards and forwards by an inch or two. Not the sound of scraping pads, but something else. Maybe one of those spring things that keep the vertical pressure on the pads?

At least the rear works. mostly. There does seem to be more travel in the brake lever, however.

I think worst case scenario the caliper needs some adjustment and the rear could do with some more bleeding before a test run. I hope the old hands have some pointers!

[Brock]

You may have a mis seated pad in the caliper, at least its easy to fix and you dont need to pull the caliper off to do it.

[STutter]

Put a screwdriver in between the pads and wiggle until something clicks?

[Brock]

Well almost, use the driver to spead the pads slightly to give a little wiggle room. Being carefull not to damage the pads.

Remove the stop bolt cap and remove (slowly) the pin, and remove the rear pad then the front pad. carefully refit the front pad, checking that the groove in the pad locates over the ridge in the front of the caliper. fit the pin and push it through leaving room to fit the rear pad.fit the rear pad the same way, tighten the pin and fit the cap. Give the caliper a wriggle to make sure it moves and is parralel to the disc.

Pump the brake to seat the pads and away you go.

[saaz]

Just check that those springs holding the pads are in properly.   Easy to get them out of place or wrong way round.

[STutter]

Haha, I'm a  moron, I put the spring in the wrong way. I was looking at it thinking it couldn't possibly have been right.

Turned it over and voila, no scritchy noise. For the record, the noise was the two little tabs supposed to hold the spring in place grinding against the edge of the rotor. Horrible noise!

So the front works, but the rear does not. I had a real lot of difficulty actually getting the larget bolt holding the caliper to go all the way into the hole. I might just make sure there isn't any more air in the system and that the spring is not installed incorrectly again.

But the bottom line - progress is being made! Test ride tomorrow and then the fairings all back on hopefully. Riding down to Bowen on Friday afternoon, so gotta make sure everything starts and stops as per normal before getting onto the highway!

[STutter]

Well the front pulls up good and there is no more groan/scrape noise when dropping the anchors in a hurry.

The rear however, seems a lot more gentle. I can't lock up the rear wheel anymore and has a lot more play in the lever. It does apply some pressure though. The claiper stis on tight, doesn't move, no air bubbles in the fluid, lever pumps the stuff through OK without hassle.

Any ideas?

[saaz]

If there are new pads in the rear it may take a while to bed in. I have always found the rear brake on the ST a bit on the weak side, and lacking feel. I have tried HH rated pads in the rear but it is not much better.  If there is more play in the lever then there is air in the system, but even when bled it has a dead feel to it

[STutter]

Thanks saaz, thats a good point. There was so much meat left on the fronts that I didn't replace them. Conversely there was next to nothing left on the rears, so I replaced them with EBC HH's

I'll keep an eye on it. I have a trip to make down to Bowen tomorrow afternoon, so hopefully everything stays together and skippy doesn't want a ride.

[Brock]

There may still be some air in the rear callipers.

[royst1100]

my 90 model has always felt soft. small amount of steel braided line made it better. last rebuild i had to bleed at every connection

[STutter]

Well the brakes are doing quite well.

The rear has gotten a bit more feeling in it and the front are great. As I mentioned, no more weird noises when the front brake is used.

I think the rears (as they were new) needed some bedding in and so are progressively getting better. Im quite chuffed that I've done it myself too, even though its fairly basic. I'll take these skills and be able to apply them to my other bikes and save a boatload of cash in the process.

And given the clutch now has fluid in it  , it works a lot better. Still a bit clunky at times, but thats more the clutch itself possibly.

[STutter]

Well its almost been a year and I'm off around Australia tomorrow and its all happening.



Im a bit time poor, so I budgeted a couple of days to do everything I needed to do to the bike. Anyway, the last thing I wanted to check was the rear caliper as it was never really 100%.

Anyway, I still had to pop one of the pistons out with air, regreased and put it back in, and I also noticed the brake pads had not worn evenly. When placed together they are worn 2 degrees off to the left, instead of being straight up and down (say 90 degrees) with even wear. Also, that 14mm bolt never really went back into place, leaving a 3mm gap.

I think the caliper is not sitting parallel with the rotor, and the bolts are to blame.

Stupidly, I just decided to outsource the work to a mechanic so I could get my study done for an exam I have today. Anyway, they dont know anything about ST's and I regret sending it there as it was supposed to be a quick and easy job - now however, we are at 4 hours of labour while we learn on the job so to speak.

In the past, I've tightened up the smaller bolt first towards the rear of the caliper, and then tried to tighten the front. Am I doing it wrong somehow? You'd think with 4 moving parts that it would be straightforward. If anyone could chime in and save me a dollar or two in labour, I'd be happy to hear it

[saaz]

I don't think the order really matters, but I recall that it is possible to not have the hex head bolt at the front slightly of line, and the caliper does not slight smoothly, leading to uneven wear or even the brake binding.