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Discussion Starter #1
2013 Camhead RT here,

I have searched and read the related threads, and also read a step-by step for an older model from Jim VonBaden. I couldn't find any good videos. I have bled quite a few motorcycle and car brake systems, including R100 ATE calipers and R100 Brembos, but I had never before thought that I need to push the caliper pistons back into their bores. Perhaps this has something to do with the bleed nipple being beside the inlet fitting. Am I making something simple into something complex? (seems to sometimes be the case with my bike)

Thanks and cheers,
 

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2013 Camhead RT here,

I have searched and read the related threads, and also read a step-by step for an older model from Jim VonBaden. I couldn't find any good videos. I have bled quite a few motorcycle and car brake systems, including R100 ATE calipers and R100 Brembos, but I had never before thought that I need to push the caliper pistons back into their bores. Perhaps this has something to do with the bleed nipple being beside the inlet fitting. Am I making something simple into something complex? (seems to sometimes be the case with my bike)

Thanks and cheers,
Its the same as any brake system. You don't *have to* press the pistons back into the caliper, but by doing so, you're ensuring that you're flushing as much of the old fluid out and replacing it with fresh fluid.

If you don't push the pistons back into the calipers, there is more volume of fluid left in the caliper and the path of least resistance for the new fluid may be past those areas rather than through them. You'll mix some new fluid with whatever fluid that's left in there, but likely not flush it all.

If you're already going through all the trouble to flush the fluid, pushing back those pistons just makes sense IMO to get the result to be as complete as possible.
 

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Discussion Starter #3
Its the same as any brake system. You don't *have to* press the pistons back into the caliper, but by doing so, you're ensuring that you're flushing as much of the old fluid out and replacing it with fresh fluid.

If you don't push the pistons back into the calipers, there is more volume of fluid left in the caliper and the path of least resistance for the new fluid may be past those areas rather than through them. You'll mix some new fluid with whatever fluid that's left in there, but likely not flush it all.

If you're already going through all the trouble to flush the fluid, pushing back those pistons just makes sense IMO to get the result to be as complete as possible.
Makes sense, thanks. Would I remove the pads and press the pistons in with a pry tool of some sort? Hoping not to remove the front wheel or the calipers for this little job.

Thanks again.
 

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Makes sense, thanks. Would I remove the pads and press the pistons in with a pry tool of some sort? Hoping not to remove the front wheel or the calipers for this little job.

Thanks again.

You don’t have to remove the wheel. I have a 13 as well. Brakes are like 10 minutes. Leave the old pads in to push pistons back in, then remove and replace with new pads


2013 BMW R1200RT 90 Years of Motorrad 2014 Harley Davidson Street Glide

Past Bikes:
2009 Suzuki GSX-R 600
2009 Suzuki GSX-R 1000
 

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You don’t have to remove the wheel. I have a 13 as well. Brakes are like 10 minutes. Leave the old pads in to push pistons back in, then remove and replace with new pads
And if you're just flushing the fluid (not changing the pads) you can push the pistons in using the pads and no need to replace them... using them to push the pistons back in shouldn't damage them (if it does, then you're doing it wrong, like with a chisel or a screw driver).

Personally, I remove the calipers to do this, but you may not have to. Be sure to take some fluid out of the master cylinder first so you're not overflowing it (and getting brake fluid all over your bike) as you push the pistons back in.
 

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If your concerned about performing a complete thorough brake system flush then make sure you flush the trapped fluid in the ABS module as well.
 

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Discussion Starter #7
If your concerned about performing a complete thorough brake system flush then make sure you flush the trapped fluid in the ABS module as well.

I understand from reading that, to do this, I need the proper electronic tools?

As I hinted in my first post, sometimes things are not as simple as I first think that they might be.

Thanks, Alan
 

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2013 Camhead RT here,

I have searched and read the related threads, and also read a step-by step for an older model from Jim VonBaden. I couldn't find any good videos. I have bled quite a few motorcycle and car brake systems, including R100 ATE calipers and R100 Brembos, but I had never before thought that I need to push the caliper pistons back into their bores. Perhaps this has something to do with the bleed nipple being beside the inlet fitting. Am I making something simple into something complex? (seems to sometimes be the case with my bike)

Thanks and cheers,
It's always a good idea to push back the caliper pistons, regardless of vehicle, to make sure that you flush out ALL of the old fluid! It is more important in the caliper areas, because that is exactly where the brake fluid is degraded, and burnt, from the high heat from the piston, That particular bits of fluid inside the caliper cylinder is the most degraded of them all!!!! If you hadn't done this in the past, again regardless of vehicles, then you have not done a proper job of flushing. You can buy tools to push back the piston, but if you looked at JVB video, you will see him using a pair of tapered wooden shim to do the job without having to remove the pads. The tool that you buy (I have one) requires you to remove the pads, and I prefer to do that, because it's very easy to do on the RT, and it gives me the opportunity to check the friction material thickness.

Look at the note at the end of this pictorial: http://www.jimvonbaden.com/R1200_2007_brake_bleed.html
 

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I understand from reading that, to do this, I need the proper electronic tools?

As I hinted in my first post, sometimes things are not as simple as I first think that they might be.

Thanks, Alan
That does NOT needed to be done!!
 

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That does NOT needed to be done!!
PadG is correct. The newer style ABS is a straight pass thru until it actually activates and then it does trap fluid but returns it as soon as the ABS event is over. No trapped fluid to flush.
 
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Discussion Starter #11

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Also wondering - does the "linked brake" system enter into this at some point? Do I open the rear bleeder while squeezing the front brake lever, to push fresh fluid back to the rear?
Sorry to be so full of questions, but I am dreading this brake flush job more than usual, due to the high probability of spilling fluid on the considerable expanse of plastic panels and having a real mess/paint damage, despite my being careful and covering everything.

Thanks.
 

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One note here, and perhaps it is obvious to most, but when you push the pistons back, do it with the bleeder open. If you do it with the bleeder closed you will force the dirty fluid back toward the ABS components and master cylinder rather than just ejecting it.
 

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PadG is correct. The newer style ABS is a straight pass thru until it actually activates and then it does trap fluid but returns it as soon as the ABS event is over. No trapped fluid to flush.
Thank you! Finally, somebody else who actually understand how things works.
 

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Also wondering - does the "linked brake" system enter into this at some point? Do I open the rear bleeder while squeezing the front brake lever, to push fresh fluid back to the rear?
Sorry to be so full of questions, but I am dreading this brake flush job more than usual, due to the high probability of spilling fluid on the considerable expanse of plastic panels and having a real mess/paint damage, despite my being careful and covering everything.

Thanks.
Don't worry about it! It is as easy as it sounds, and no you don't have to worry about the linked brakes. I'll post the BMW instruction below.



There are always myths and misinformation that are propagated by people who simply parrot what they had heard without real knowledge of what they are talking about!


Here are the sheets on what BMW tells you to do:


Rear: https://www.bmwlt.com/forums/attachments/rt-series/126569d1495562963-gs-911-brake-flush-rear.pdf


Front: https://www.bmwlt.com/forums/attachments/rt-series/126561d1495562963-gs-911-brake-flush-front.pdf
 

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Thank you! Finally, somebody else who actually understand how things works.
And I didn't even stay at a Holiday Inn last night:). I'll admit I did have to research it as I am very intimate with the older "wizzy or servo" brakes, but the new ones intrigued me as they are on EVERTHING these days.
 
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@;
PadG is correct. The newer style ABS is a straight pass thru until it actually activates and then it does trap fluid but returns it as soon as the ABS event is over. No trapped fluid to flush.
What’s considered newer style? I have a 2012 and motoscan etc. so is there any advantage even if not required?

Thanks!
 

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Hi guys

Great information as usual. In all the years I have done everything but brake fluid change. Always chickened out on that one.

It's finally time to do it myself and I do have all the gear to do so..sitting there brand new for a couple of years.

My biggest worry is getting brake fluid on any of the plastic/painted surfaces.

Questions:

1) Can I use Glad wrap to protect the surfaces (If not what else is suitable)???
2) What cleaning fluid can I use, other than water, to wipe off any slight spill straight away ??????
 
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