MOTOBRICK.COM

TECHNICAL MOTOBRICK WRENCHING In Remembrance of Inge K. => The Motobrick Workshop => Topic started by: frankenduck on April 01, 2012, 10:02:05 PM

Title: Changing Front Brake Pads on a 4V K Bike
Post by: frankenduck on April 01, 2012, 10:02:05 PM

In this case the patient is my 94 RS. 

(Since the K1100LT has an 18" front wheel its easier to get the calipers off to do this but on a K1100LT you do need to remove the rear half of the front fender to gain access to the caliper mounting bolts.  The fender has to be removed on a K1 as well.)


Tech data:

Min. Brake Pad Thickness	1.5 mm
Brake Fluid	DOT 4 compliant
Min. Front Rotor Thickness	4.5 mm	0.177 in
Caliper Mounting Bolt Torque	40 Nm	29.5 ft-lbs
ABS Control Unit Bleed Valve Torque	9 Nm	6.6 ft-lbs or 80 in-lbs
Front Caliper Bleed Valve Torque	14 Nm	10.3 ft-lbs or 124 in-lbs
Brake Pad Part Numbers:
BMW Front Brake Pads (pair)	34117663764
EBC Organic Pads (pair)	FA246
EBC Sintered Pads (pair)	FA246HH	(Sintered pads bite better but wear rotors faster)
Galfer Pads (pair)	198	Organic - I think

You'll need two pairs of brake pads - one pair for each caliper.

The K1100RS, K100RS4V and K1 bikes all have a 17" wheel in the front. Because of this you can't just unbolt the calipers and pull them off of the rotor.  In order to get them off you'll need to spread the brake pads apart enough to remove the caliper.  I've found that the easiest way to do this is to slightly loosen the bleed valve on the opposite caliper, lift the caliper most of the way off of the rotor and then rotate the top of the caliper towards you to spread the pads apart so that the caliper can be removed.  If you try to do this without loosening the opposite bleed valve then spreading the pads sends a lot of backpressure to the master cylinder which its seals are not designed to take so the front master cylinder may start leaking.  You might also want to put a small towel on the top of the caliper to keep it from scraping the wheel rim as you remove the caliper.

Right bleed valve opened to remove left caliper:

Then tighten the bleed valve.

The brake pads are held in place in the caliper by a pin that goes through the top of the caliper.  All you need to do is tap that pin out from the  back (inside) of the caliper.  I've found that a common nail set with a few light taps from a hammer is a good tool for getting the pin started.  Once you've got the pin started you can grab it with a set of pliers from the front (outside) of the caliper and the pads will fall right out of the caliper.

Nail sets:

In this case I was at my dad's place and didn't have a nail set handy so I just used a big nail:

By the way, the springy wires at the tops of the brake pads are there to eliminate high frequency vibration of the pads when the brakes aren't being used, thereby eliminating disc brake squeal.

Install the new pads in the caliper and replace their retaining pin.  Put a very light coat of WD-40 or whatever on the tip of the retaining pin and twist it with some pliers as you're inserting it to avoid the tip of it getting caught on and bending the anti-squeal wire on the top of the inside pad.

Since you've just installed thicker brake pads then you may need to spread the pads a little more in order to get the caliper back onto the rotor. 

Reinstall the caliper and torque it's mounting bolts.

Repeat the procedure for the caliper on the other side of the wheel.

While you're fiddling with your brakes its probably a good idea to bleed them once you got the new pads installed.  Bleed at the ABS modulator first, then the calipers.  On ABS II bikes the rear bleed valve on the ABS control unit is for the front brakes.

Title: Re: Changing Front Brake Pads on a 4V K Bike
Post by: Duc750 on April 06, 2012, 04:33:48 PM

How do you find EBC pads on the BMW discs ?

Only reason I ask is every none EBC disc I have ever used EBC HH pads on has been eaten u in hundreds of miles. Ferodo pads (if you can get them over the pond) seem to be significantly better on OE discs (Platinum series). They don't last as long as EBC pads but pads are cheaper than discs !

Title: Re: Changing Front Brake Pads on a 4V K Bike
Post by: frankenduck on April 06, 2012, 05:43:33 PM

Quote from: Duc750 on April 06, 2012, 04:33:48 PM

How do you find EBC pads on the BMW discs ?

Only reason I ask is every none EBC disc I have ever used EBC HH pads on has been eaten u in hundreds of miles. Ferodo pads (if you can get them over the pond) seem to be significantly better on OE discs (Platinum series). They don't last as long as EBC pads but pads are cheaper than discs !

I use regular EBC pads on my LT and K75(w/ K1100 front discs) and they seem to work fine.  I've never used HH pads because I've never seen a need for them so I can't comment on actual results - it's just what I've heard.

Title: Re: Changing Front Brake Pads on a 4V K Bike
Post by: mystic red on April 06, 2012, 06:18:34 PM

Never lacking for a green bottle around there, are ya?! :neener:

Title: Re: Changing Front Brake Pads on a 4V K Bike
Post by: Snowy on April 07, 2012, 03:11:52 AM

I use EBC HH sintered pads and they are brilliant at hauling the K1100RS to a quick stop - I don't know if they are different between US and Europe supplies though. I tend to be fairly light on the brakes in general use so my pad and disc wear is good but when you need to use them in anger they really were an excellent swap from whatever was fitted as OEM.

Title: Re: Changing Front Brake Pads on a 4V K Bike
Post by: DRxBMW on April 07, 2012, 08:21:55 AM

Quote from: frankenduck on April 06, 2012, 05:43:33 PM

Quote from: Duc750 on April 06, 2012, 04:33:48 PM

How do you find EBC pads on the BMW discs ?

Only reason I ask is every none EBC disc I have ever used EBC HH pads on has been eaten u in hundreds of miles. Ferodo pads (if you can get them over the pond) seem to be significantly better on OE discs (Platinum series). They don't last as long as EBC pads but pads are cheaper than discs !

In spite of faster wear, the Galfer Green organic brake pads pads are my fav. All weather bite, easy on your rotors,fairly quiet.

R&R the MTB with fanchy schmancy ceramic pads. I must admit they do work well,far superior to the the Galfer for heat dispersion.

However, rare that I ever heat up my brakes on the brick.