Caliper service

[Tally]

I've just serviced my brake calipers and what a palaver that was , it took me just over an hour to remove one piston it was well stuck. Anyway they are all done now with the help of some Autosol and red rubber grease they all slid back into their cylinders like hot knife through butter. For your perusal here are some pictures.

[Big Phil]

Looking good Mate 👏👏👏 Out of interest how did you get the stuck piston out?

[Tally]

@Big Phil  I used a pair of pliers and an old piece of inner tube . Fold the tube over to make a cushion over the piston , grab with the pliers and twist and pull at the same time. The problem I had was the piston would spin but not pull , after an hour of grunting,swearing and sweating it finally gave way. Once I cleaned the seal recesses out and greased (red rubber) the piston it went back in sweet as a nut.

[GSXKING]

How old and how many miles/km's has the bike travelled ?
Did you notice a degradation of your brakes at all ?

I'm just curious as my bike is still original.

[Tally]

Hi GSXKing, my bike is 13 yrs old and has covered 15th miles (24th Km's) . The trouble is that my bike lives outside and doesn't get used much (covid and other issues delaying getting out). The brakes suffered from road salt and dirt and started binding , not too bad but enough to make them judder especially when you're braking from 10mph to zero, the noise was audible even with ear protectors in and your lid on so apart they came, now they're ready to go back on weather permitting at the moment (raining). Hopefully they will be more responsive and a lot quieter, (report to follow).

[Hooli]

I always find the lever goes spongy & feels wooden once a piston sticks.

[V_i_c_i]

Autosol is fine .. just cleaned, no new paint on calipers.  Just bolt have new cover - Cu+Ni plating.

https://www.motorkari.cz/motorka/?mid=68345&act=moto-denik-detail&ddid=58444

[BlueDragon]

Saw this on done on Youtube and thought I would try it out today.

Decided to service the front brakes on the 1400 as the lever was getting a little spongy and after I removed the calipers I notice 2 pistons in one caliper were not moving freely and the other caliper had one piston that was not moving freely.

Used a small socket as you can see in the photo along with an extension bar attached to the socket wrench/ratchet.  They jam into each other when in the piston and you try and use the socket wrench in the ""tightening" direction.

As you continue to turn the ratchet, the piston will spin and move outwards as you turn.  Pops straight out very easily, even the stuck pistons came out without problem.  I've tried this on the previous 6 piston caliper which had half the pistons seized and they all came out without issue.

Not sure how anyone else bleeds empty brake calipers/lines.  But I would recommend to make sure the pistons are pushed all the way into the caliper and with the brake pads installed, then put something in between the pads to keep the pistons inside the caliper. Then bleed the brakes like that.  It makes it easier to get all the air out of the caliper as the piston takes up all the space.  then when all the air is gone, bolt the calipers back in place loosely with about 1/2 a turn to go on the caliper mount bolts and slowly pump the brake lever and refill the reservoir as needed. Once this is done, I then hold the brake lever on while tightening up the mount bolts with thread lock to the proper torque.

Provided you don't have any air stuck in the master cylinder, your brake lever should now be really very firm.  I barely need 2 fingers on the brake lever with braided lines as well. Only the slightest amount of pressure is needed to stop.

These are the SV1000  calipers that I fitted to the 1400.

I'll get around to rebuilding the original 6 piston calipers once day as spares.

[grog]

All good advice Blue. 👍Dont reckon mine are as good as was. Must have a look. If only our pistons had a rubber boot over them like cars.

[Tally]

A nice afternoon today so I decided to mount my brake calipers on the bike , all went well , annealed the copper washers then fitted the banjo bolts all torqued down nicely as did the caliper joining bolts , bled the brakes the old fashioned way, no dramas until the very last mounting bolt decided to snap so got to order some new ones . Now I've got the trial of removing the remainder of the bolt from the caliper, hopefully it will wind out oy vey 

[Tally]

Just ordered  4 new titanium hex bolts as I've got to replace one I might as well change the others, better safe than sorry 

[Hooli]

Should have ordered six and done the rear too.

[Tally]

Yeah didn't think of that hooli, I'll order them another day. A pic of one snapped bolt

[Hooli]

One of mine snapped like that years ago when I was having tyres fitted, lucky it wound out ok & they found a bolt that fitted to get me home. Then last winter another one did it, so I went down the local fasteners place & got six normal bolts the right size & used washers with them.

[BlueDragon]

I realise bolts get old etc and do snap and in many cases should be replaced anyway on a schedule.

But are you guys using a torque wrench to tighten these bolts?

I've never snapped a bolt when I've used torque wrenches.  I have several in my workshop.  Worth the money. I use them all the time. The only time I use a non-torque wrench is when I am loosening stuff to take things apart.

The caliper mount bolts, according to the Suzuki genuine workshop manual I have only need to be tightened to 18 lb-ft or 25 N-m.  Used with some thread lock as well.

the caliper bolts that hold the two halves of the caliper together only need 15 lb-ft.