Bmw K1300s Master Cylinder for sale | eBay

Get the best deals for Bmw K1300s Master Cylinder at eBay.com. We have a great online selection at the lowest prices with Fast & Free shipping on many items!

www.ebay.com

 

Thanks for the suggestion, but there is no guarantee 2nd hand won't have the same issue and with no seal kits available for these, it's not as if I can renew it to new (otherwise I'd just get my current one refurbished)

I guess seeing as the existing master cylinder is 16 years old, if I do get a new OEM, it would likely outlive my usage of the bike and it keeps the bike original... That's my thinking.

I was just curious to know what others may have done.

 

Might be a bit simplistic but have you replaced the fluid? I’m thinking maybe air in the line.

 

Fluid was replaced about 5k miles ago at a BMW main dealer, granted this was 5 years ago (she's not had the usage she deserves!)
Maybe I should just get it changed and go from there.... The sudden loss it experiences really doesn't feel like just changing the fluid is the fix. If constant air in the line, I'd expect it to occur consistently, however it happens randomly, without warning.

 

If it was last changed 5 years ago, I’d definitely start there. Manuals recommend every 2 years. Although your symptoms do sound like the seals are worn on your master cylinder.

 

I would certainly start with flushing and bleeding it first. Air in the lines can cause the symptoms you describe. It will pump up as the air bubble are reduced in size from pressure and go soft as the bubble increase in size. Apart from anything else it’s a cheap way to start and if it works…

 

Make sure they bleed from the bottom up. I have had little luck bleeding from the top down.

 

Are you thinking of the clutch? The brakes are easy both directions

 

If you decide the fluid replace option first, a handy tip is to a) not go to the stealers, and b) work slowly and methodically, i use a small spanner to tap the fittings and line as you bleed, helps to release trapped bubbles. A clear hose from the brake caliper to the bleed jar (so you can see the bubbles leave) and ensuring the master resevoir is kept above minimum helps to prevent air ingress.

If going to replacement of MC, I've had good experience with HEL, and I'd be replacing both MC and lines. Their customer service has (for me at least) been top notch. Oem is Brembo i think. It's also good gear.

NB: Never ever reuse old banjo's or crush washers for brake systems, that's asking for trouble.

 

Another tip: Get a 100ml syringe and the proper size clear tubing (I used food-quality silicone tubing.) and make yourself a poor man’s vacuum bleeder.

Instead of pumping the master, open the bleeder and use the syringe to draw the fluid out Starting with the caliper furtherest away from the master. When you get no more bubbles, move to the other caliper. Don’t forget to keep the reservoir topped up.

 

Brakes are important, when owning these bikes you always need a large amount in the, Just in case pot, I do have faith in the BMW tech`s, they are working on these bikes everyday.
I would personally bite the bullet, Call BMW order the part and book it in for the work to be done, at this time of year they give out winter discounts. I just had a minor service, brake fluid, engine oil and diff oil changed, for £408 reduced to £340.
That work would have took me 3 days, with my preferred overnight breaks. Get the work done and enjoy the bike this summer.

 

Bleeding brakes and service should take about a couple of easy hours and is easy. If the brakes don’t respond to a bleed there will be further substantial expenses to replace parts. I would save the £340 and put it towards any further expenses.

 

When you`ve owned a bike for 14 years and has a full BMW service history, £340 along with a thorough health check, is money well spent, in my opinion.

 

Axit2 you are fortunate to have found technicians you can trust. My riding buddies have had fairing bolts missing,a sump plug that came out on a ride leaving oil all over bike and tyre. More than one example of technicians not being able to diagnose a fault and just replacing parts until they solved the problem. They didn’t, but a $3700 bill just the same. I’ve owned my bike for 17 years and done all the work myself. Including the clutch, replacing the suspension with Wilbers, timing chain and sprockets etc etc. i guess what I’m saying is if I do the work myself I know it will be done conscientiously. I have had nearly 70k miles of total reliability and saved thousands of dollars over the years. You pAys your money and you makes your choice. Pun intended😃.

 

I think I have found a good dealer, they are a family run Franchise and seem a lot cheaper than the usual, that is why I have continued using them, every thing they touch is torque marked, I even get a torque mark on my oil filter. I have heard the horror stories and always check their work.
I just find every thing on the K13GT is such a faff, GS911 needed to bleed brakes, air compressor needed to fill coolant, all tupperware to be removed and radiator out to remove spark plugs, special tool to remove coil packs etc.

I paid £670 for a valve check service, my mate paid £1250 for a Kawasaki.

I`ve had a buckle on my front wheel since 2015 when a gorilla was new to fitting Michelin GT tyres, when my dealer put a new tyre on they straightened the wheel as part of the service, I was impressed with that.

I know it`s expensive, but, I knew that when I got the bike.

 

Does this happen only while riding or does it also happen while stopped and the brake lever is cycled?

 

5 years eh? Change fluid and bleed. Flush it well. Inspect the system for leaks.
It could be a tiny strand of the foam pot scrubber in the reservoir is drifting back and forth past the seals on the master's piston.

If its a tiny leak take care someday its not going to come back by cycling the lever if the fluid is dropping.

The piston may be partially sticking and not fully returning to its ready position as well due to contaminants or a weak spring or being cocked askew slightly.

Does anyone here have issue like this? I don't but I change the fluid regularly and flush the reservoir clean.

Do you have a scan tool to check the computer for warning re: ABS? I assume any would illuminate the idiot light on the instrument panel but maybe not. But hey lets not stampede off to a failing ABS pump.

 

ths may help.....................

 

You mention you checked the discs, but this sounds like a warped disc or similar moving the brake pads off the disc are the brakes good once you reapply the brakes when the lever goes to the handlebar. Is this only after a long time between applying brakes? Does the lever otherwise feel OK and goes to the same position in traffic riding?

 

Good point ChrisAuz, a warped disc can knock pads back into the caliper.

 

Lever would pulse.........

 

Another culprit could be the wheel bearings. I asked a question about when this happens and the OP hasn’t responded back yet.

 

Wheel bearings give off a low rumble and of course cause a wobble. Get the bike on thr centre stand, then jack and block of timber under the headers and lift front wheel off the ground. This will allow you to rotate the wheel by hand and try to see if theres any side to side play.

 

Not in my case. No rumble. No wobble. Just an occasional brake lever to the grip when stopping. After one pump, I was good to go.
The brake pads will keep the wheel from wobbling, so you won't notice any side to side play unless you remove the calipers.
Here's a picture of the damage.

 

He's bluffing!