Changed pads -> brakes stuck on!

[SammyTheSnake]

Pop quiz:

I've just changed all the brake pads on my ST1100A and now every time I use the front brake, it stays on even when I release the lever. Of course, as I have the wonderful / awful CBS brakes, this means the rear brake also comes on and before long I've got six smoking pads and not much forward motion! A quick wiggle of a screwdriver between the pads on the front right caliper gets me going until the next time I need to stop...

What did I do wrong? :-(

Cheers & God bless
Sam "SammyTheSnake" Penny

 

[SteveST1300]

Did you clean the pistons in the caliper you may have dirt in there.

 

[George]

How many miles?

Probable caliper rebuilds in yur near future. Search for Mike Martin's home page, full instructions there. I recommend new seals in all the pistons, but a a minimum full disassembly and cleaning.

Pushing the pistons in without proper cleaning just leads to down-the-road problems.

 

[Mark]

Micheal's home page... a whole lot of great information on ST1100s.
http://home.insightbb.com/~mmartin36

 

[SammyTheSnake]

Yeah, it looks like a dismantle / clean / rebuild cycle is in the near future! The bike's got 95,000 miles on it, though I don't know how recently the brakes were overhauled - at least not in the ~6000 miles / 4 months since I've had it.

I'm trying to make head / tails of the fiche on Ron Ayers, there are three part numbers for the dust seals and the numbering is confusing (what do the numbers in brackets refer to?) and I'm not sure how many of each part number I'll need to order.

My bike's a '97 made ST1100A (year letter is V) and I'm looking at the fiche here: http://fiche.ronayers.com/Index.cfm/Module/Main/TypeID/26/Type/Motorcycle/MakeID/1/Make/Honda/YearID/38/Year/1997/ModelID/7316/Model/ST1100A/GroupID/318809/Group/FR_BRAKE_CALIPER_-_ST1100A_96-98

Also, George, as a guy who's right near the top of the 2009 miles board, what do you *do* to average over 200 miles a day? I'm commuting just under 100 miles/day (weekends excepted) but it'll take me a while to catch you up ;-) are you just touring the US all year around? Maybe some day I'll retire and spend my days exploring Europe in the same way

Cheers & God bless
Sam "SammyTheSnake" Penny

 

[schlep1967]

Also, George, as a guy who's right near the top of the 2009 miles board, what do you *do* to average over 200 miles a day? I'm commuting just under 100 miles/day (weekends excepted) but it'll take me a while to catch you up ;-) are you just touring the US all year around? Maybe some day I'll retire and spend my days exploring Europe in the same way

What does George "do"? George rides. Then changes tires and rides again. Most all of us want to be him (or at least live his lifestyle). :bannana

 

[George]

Can't help with part numbers, mine aren't A's.

As to keeping up the average, ya just have to...

GO RIDE!!!​

I've been home 14 days since Easter. That prolly 'splains a lot.

 

[BigTom]

Don't let him kid you, he rides when he's home, too.

 

[SammyTheSnake]

Well, a status update:

I managed to undo *one* of the bolts holding the caliper on the fork, the one at the top is resisting all my attempts using a large allen key, a long socket wrench (and half a dozen adapters, one of which broke!) and an impact driver (the hit-it-with-a-hammer type) I even tried gentle blowtorching but didn't want to use too much heat that near various rubbery bits. Any more ideas I could try, other than giving up and getting a proper mechanic to do it for me?

I proceeded with the caliper still attached, but swung away from the disk by about 30 degrees.

I used the brake lever (and pedal) to push out the pistons one at a time (holding one back with a bit of wood to get the other out) as far as I dared (question: how far do they come out before they plop onto the floor and spill all my brake fluid?)

With (awkward) access, I cleaned the pistons with a bit of wood to scrape off the accreted cack - mostly crusty black powder which I figure is pretty likely to just be brake dust.

Having done as much scraping as I could do with the restricted access I had, I then used a toothbrush loaded with brake fluid to hopefully get the rest off. Frustratingly, the dirtiest piston was the top one, which gets first dibs on the dust thrown out the top of the brake pad by the disk and that piston was also by far the hardest to get useful access to with the caliper still attached by its top bolt!

I've currently got a pad retaining spring sitting on the sideboard while I try to figure how on earth to get it back in place (the diagrams in the Haynes manual are useless, the ones in the Honda manual are *nearly* useless, and the Ron Ayers fiche is marginally useful! I'll have a good close look at the matching part in the left hand caliper!)

The pistons now move back with (a lot of) finger pressure, which I can't imagine I'd have been able to do previously, so I'm hopeful this will be the bunny when I try to put it all back together tonight!

If the problem isn't sorted, I'll have to take the caliper off altogether to do a better job of cleaning the pistons and to get new dust seals in there, so I might have to admit defeat and get somebody else to work on my bike, boo! :-(

Cheers & God bless
Sam "SammyTheSnake" Penny

 

[RaYzerman]

Sammy, you're almost there..... this job is worth doing well and properly, and you will not believe the improvement when you're done. The pistons probably won't pop out until you've got them out against a 1/4" or 1/2" piece of plywood spacer (or one brake pad), but make sure you have them all out as much as you can before removing them. Just cleaning them off is OK, but you'll be doing this again in the not too distant future, so just do it now and get it over with!! Once you've got all the pistons pushed almost out, remove the brake lines and take the calipers to the bench. Remove all pistons, and clean them with brake cleaner and use 0000 steel wool or crocus cloth sparingly to polish them up so no residue remains. Remove the dust seals and the main seal inside the calipers and clean the crud out of there. Lube the new seals with brake fluid or a light coating of silicone grease and install. Dip the end of the pistons in brake fluid and insert. Notice how nice they slide now!!!
Pump out all the old brake fluid, remove reservoir caps and clean the accumulated crud, wipe with isopropyl alcohol, blow with air to ensure no lint, etc. Reassemble everything, new pads, and proceed to fill with fresh fluid. Open bleeders and flush new fluid through, and then bleed per proper procedure (if you have ABS/linked brakes).
You will not believe how nice and new it works, and definitely worth doing!!!! You're now good for years.... with a flush with new fluid every couple of years or so. When you next replace pads, do what you did, cleaning pistons of all external contamination before putting the new pads in.
I did this on my '83 Magna with 95,000 on it, and the brakes worked like new and were much firmer, with the new bike stopping power.

 

[jvick98]

Ray, good write up.

Sammy, a safe way to remove pistons is to wrap the caliper with a shop rag and blow the pistons out with air pressure. If you get a stubborn one, replace the one that came out easy, hold it in with a piece of wood, wrap with shop rag and put the air to it again. The stubborn one should pop out.

Jim

 

[George]

Ray, good write up.

Sammy, a safe way to remove pistons is to wrap the caliper with a shop rag and blow the pistons out with air pressure. If you get a stubborn one, replace the one that came out easy, hold it in with a piece of wood, wrap with shop rag and put the air to it again. The stubborn one should pop out.

Jim

I pump'em out using the master cylinder. As one gets close put a block in the way of it so the other will move.

I've used air before and had to hunt down the errant looser piston that flew passed my face and landed in the nether regions of the garage!

 

[SammyTheSnake]

George, that's what I did, it's the only plan that makes any sense to me. I see no reason to start shoving air into a hydraulic system, especially if it creates high speed projectiles!

Cheers & God bless
Sam "SammyTheSnake" Penny

 

[George]

Just did a halfassed rebuild on Mark's rear caliper today at YooperSTOC. Complete disassembly, minor repair to the dust seals and flipped'em 180 degrees, dug all the crud out of the seal grooves, and reassembled. Works WAY better than before and probably bough him another thousand miles. His pads weren't completely gone and this will save'em. An hour of our time to assure a safe return home where he can order parts and do it right.

 

[RaYzerman]

Ray, good write up.

Sammy, a safe way to remove pistons is to wrap the caliper with a shop rag and blow the pistons out with air pressure. If you get a stubborn one, replace the one that came out easy, hold it in with a piece of wood, wrap with shop rag and put the air to it again. The stubborn one should pop out.

Jim

Really stubborn ones won't come out with air. Need hydraulic pressure to move it. It's best to do it while they are still connected to the bike.

 

[broc11]

thanks for the info,having similar issues now with my st1100 ay model

 

[ST1100Y]

I've used air before and had to hunt down the errant looser piston that flew passed my face and landed in the nether regions of the garage!

This is where the strip of wood comes usefull ;-)

I've build myself an adaptor using an old brake hose with an air-coupling on the other end.
Drain all the brake fluid, remove caliper, insert the wodden piece, attach the air nozzle... and BANG! out they are...

Refurbing an abused '94 I found automotive wheel/rim cleaner very usefull for cleaning those bits, deals brilliantly with all the crud there.
Spray on (see product label for max soaking time), then quick use of a nylon brush and rinse in warm water; repead if required and wear rubber gloves as many of those products contain traces of sulphuric acid.
Check the pistons for any scratches or defects on outer walls, if some are noticable, replace them.
Remove the rings with great care (dental pick) and replace them as well.
To clean the groove inside the caliper mentioned wheel cleaner again helped a lot, still persistent christals got scraped out with a bend clothhanger wire which tip clipped and filed accordingly.
Use great care, do not scratch any surfaces!

Wipe new rings and outside of (new) cylinders with brake assembly grease prior insertation.

And, depending on year, milage and TLC-status of the vehicle, I'd also consider overhaul kits for the master cylinders while at it.

Also replace the aluminum gaskets on all banjo couplings you'd worked on.

 

[Bigmak96]

+1 on the suggestion John has posted. If that is not positioned correctly it will cause your issue.
Good luck.