Author Topic: Replacing the rotor disc & upgrading to 4 piston.  (Read 946 times)

Offline Matt Chapter

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Re: Replacing the rotor disc & upgrading to 4 piston.
« Reply #15 on: May 26, 2020, 12:51:12 PM »
Mucci, do you have the dimensions for the braking rotor you got?  While I've got my caliper off I'm going to replace the rotor too, and I'm either going to replace just the rotor with a braking one, or get an EBC.

The EBC I'm looking at is https://ebcbrakesdirect.com/motorcycle/bmw/r80-r-80-rt-single-rotor/1984-1990/31695

Edit:  Did some looking, looks like the rotor for my mono shock is this one.  The twin shock rotor is 260mm, mine is 285mm, which checks out with my paperwork from Spiegler.

http://www.braking.com/catalogue/dettaglio_prodotto.php?codice_articolo=BW02FI
« Last Edit: May 26, 2020, 01:19:13 PM by mchapter »
'86 R65 with '84 motor ~67000 miles. ?SS lines, Spiegler rotor, Progressive monoshock, Keihan silencers, a piece of Pichler fairing.
'76 CB400F ~26000 miles. ?Weepy SS lines, big dent in the tank.

Offline Mucci

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Re: Replacing the rotor disc & upgrading to 4 piston.
« Reply #16 on: May 26, 2020, 03:01:37 PM »
Quote
Mucci, do you have the dimensions for the braking rotor you got?  While I've got my caliper off I'm going to replace the rotor too, and I'm either going to replace just the rotor with a braking one, or get an EBC.

The EBC I'm looking at is https://ebcbrakesdirect.com/motorcycle/bmw/r80-r-80-rt-single-rotor/1984-1990/31695

Edit:  Did some looking, looks like the rotor for my mono shock is this one.  The twin shock rotor is 260mm, mine is 285mm, which checks out with my paperwork from Spiegler.

http://www.braking.com/catalogue/dettaglio_prodotto.php?codice_articolo=BW02FI

Do you still need dimensions from the 260mm rotor? Good to know they make a 285mm too!
« Last Edit: May 26, 2020, 03:03:05 PM by Mucci »

Offline qwerty123

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Re: Replacing the rotor disc & upgrading to 4 piston.
« Reply #17 on: July 04, 2020, 09:11:03 PM »
I outline another plan (that I haven't implemented), that of moving from the stock 38mm caliper with single disk to a 48mm, here: https://www.bmwr65.org/YaBB2.612/cgi-bin/yabb2/YaBB.pl?num=1511573205/8#8

When I thought it through a while ago it was cheaper than the dual disk conversion.
« Last Edit: July 04, 2020, 09:12:12 PM by qwerty123 »

Offline Tony Smith

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Re: Replacing the rotor disc & upgrading to 4 piston.
« Reply #18 on: July 22, 2020, 10:27:12 PM »
Great write-up, but you went to a lot more trouble than was necessary to remove the rivets from the old disc. Given that you are not goign to reuse the old disc I just deployed the angle grinder and removed the heads of the rivets (ad some of the disc), a pin punch removed them whilst still warm.
1978 R100RS| 1981 R100RS (JPS) | 1984 R65 | 1992 KLE500 | 2002 R1150GSA |

Offline dogshome

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Re: Replacing the rotor disc & upgrading to 4 piston.
« Reply #19 on: August 02, 2020, 06:28:48 PM »
Hi Mucci, I like the rotors and the write up. The only thing I would change is the bracing via the mudguard/fender.

Mine was quite sensitive to road imperfections until I fitted a dual loop steel brace. i was pretty sceptical that it would do anything, but it did.

So where you have spacers to fit the standard pressed brace, I can only imagine it give a little more flex.

I find the dual standard discs quite good, now rebuilt. My friend has a Harley Sportster with single disc (+100 lb of iron engine) and describes it as puny. I can imagine a single disc on the R65 is something in between.

He never goes much above 65MPH, so for him to complain about the brakes means it really isn't great!
« Last Edit: August 02, 2020, 06:32:55 PM by dogshome »
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