Any Idea ?? Please

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Paul25001
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Any Idea ?? Please

Postby Paul25001 » Sun Jun 04, 2017 12:50 am

Hi guys and gals could anybody give me an idea of what may have happend here its the rear caliper off my R1150Rt recently purchased and cant find a complete diagram of the caliper to understand what the problem may be thanks a lot for your help


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Paul25001
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Re: Any Idea ?? Please

Postby Paul25001 » Sun Jun 04, 2017 12:53 am

Hi guys and gals could anybody give me an idea of what may have happend here its the rear caliper off my R1150Rt recently purchased and cant find a complete diagram of the caliper to understand what the problem may be thanks a lot for your help


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Paul25001
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Re: Any Idea ?? Please

Postby Paul25001 » Sun Jun 04, 2017 12:53 am

Forgot the Photo


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Jaythro
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Re: Any Idea ?? Please

Postby Jaythro » Sun Jun 04, 2017 6:57 am

They are inserts of some sort of bakelite type material to help reduce or stop Brake squeal
"Put your Ass on a motorcycle and ride with an attitude and the "Grim Reaper" will ride in your shadow!"

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Paul25001
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Re: Any Idea ?? Please

Postby Paul25001 » Sun Jun 04, 2017 8:11 am

They are inserts of some sort of bakelite type material to help reduce or stop Brake squeal
and are they NORMAL ON BM brakes ? if so where can i buy them

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Galactic Greyhound
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Re: Any Idea ?? Please

Postby Galactic Greyhound » Sun Jun 04, 2017 9:49 am

As far as I am aware, these are as Jaythro says; to stop brake squeal.

They are normal on BMW calliper pistons and likely other bikes as well.

They can also stop the pistons from sticking to the back of the brake pad and may play a part in reducing the transmission of heat to the calliper.

They likely cover a 'cupped' piston i.e. below the insert is a cavity in the top of the piston.

They are one reason why the pistons should never be levered back with a screwdriver as the inserts can be punctured/broken leaving a hole in them.

Before inserts were used, the pistons were just the 'cupped' head type so broken inserts merely put you back in that position.

You cannot get spare inserts and so new pistons are the only way to get back to the original design.

Loss of an insert/s is therefore not such a big problem and the callipers should continue to work OK.
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Paul25001
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Re: Any Idea ?? Please

Postby Paul25001 » Sun Jun 04, 2017 2:44 pm

As far as I am aware, these are as Jaythro says; to stop brake squeal.

They are normal on BMW calliper pistons and likely other bikes as well.

They can also stop the pistons from sticking to the back of the brake pad and may play a part in reducing the transmission of heat to the calliper.

They likely cover a 'cupped' piston i.e. below the insert is a cavity in the top of the piston.

They are one reason why the pistons should never be levered back with a screwdriver as the inserts can be punctured/broken leaving a hole in them.

Before inserts were used, the pistons were just the 'cupped' head type so broken inserts merely put you back in that position.

You cannot get spare inserts and so new pistons are the only way to get back to the original design.

Loss of an insert/s is therefore not such a big problem and the callipers should continue to work OK.
So would you recomend Just clean that up a litlle and put new pads in and away i go ? Until I get my speed Bleeders to do a full seal change and fluid change on the full system thanks for the info very apreciated


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Jaythro
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Re: Any Idea ?? Please

Postby Jaythro » Sun Jun 04, 2017 3:39 pm

So would you recommend Just clean that up a little and put new pads in and away i go ? Until I get my speed Bleeders to do a full seal change and fluid change on the full system thanks for the info very apreciated
Okay Check the slides slide and you can push the pistons back in with finger / thumb pressure
(Brush any dust build up off the pistons first before pushing them back in!!!! A Toothbrush quite good for this no liquids are usually required )

Are you aware If you have the "whizzy" brakes that you CANNOT bleed form master cylinder to calliper?

I don;t know if you have an ABS bike or not as they were available ABS or NON ABS but if they were ABS they were Servo assisted (Whizzy Brakes = noise from under tank with lever pulled )

Let us know and I will dig out the links for the fluid change There are 4 circuits to do and they need done Annually and Bi Annually
"Put your Ass on a motorcycle and ride with an attitude and the "Grim Reaper" will ride in your shadow!"

Islandmagee in case you're interested?

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Re: Any Idea ?? Please

Postby Paul25001 » Sun Jun 04, 2017 5:33 pm

So would you recommend Just clean that up a little and put new pads in and away i go ? Until I get my speed Bleeders to do a full seal change and fluid change on the full system thanks for the info very apreciated
Okay Check the slides slide and you can push the pistons back in with finger / thumb pressure
(Brush any dust build up off the pistons first before pushing them back in!!!! A Toothbrush quite good for this no liquids are usually required )

Are you aware If you have the "whizzy" brakes that you CANNOT bleed form master cylinder to calliper?

I don;t know if you have an ABS bike or not as they were available ABS or NON ABS but if they were ABS they were Servo assisted (Whizzy Brakes = noise from under tank with lever pulled )

Let us know and I will dig out the links for the fluid change There are 4 circuits to do and they need done Annually and Bi Annually

its a Whizzy Bike yeh I understand thats its not a Normal Bleed hoping to get the Dvd from Motibins.uk but Jaythro thanks very much indeed you have taken a great weight off my shoulders up to now


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Jaythro
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Re: Any Idea ?? Please

Postby Jaythro » Sun Jun 04, 2017 6:05 pm

its a Whizzy Bike yeh I understand thats its not a Normal Bleed hoping to get the Dvd from Motibins.uk but Jaythro thanks very much indeed you have taken a great weight off my shoulders up to now
Here ya go http://www.ukgser.com/technical/nick/Br ... 707%29.pdf
"Put your Ass on a motorcycle and ride with an attitude and the "Grim Reaper" will ride in your shadow!"

Islandmagee in case you're interested?

Paul25001
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Re: Any Idea ?? Please

Postby Paul25001 » Sun Jun 04, 2017 7:33 pm

its a Whizzy Bike yeh I understand thats its not a Normal Bleed hoping to get the Dvd from Motibins.uk but Jaythro thanks very much indeed you have taken a great weight off my shoulders up to now
Here ya go http://www.ukgser.com/technical/nick/Br ... 707%29.pdf

That is Brilliant reading and has probably daved me a lot of money now just have to find the appropiate speedbleeders and with some Tlc have a go Thanks a lot


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