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1Back to top Go down   1990 K75S (ABS) Replacement discs. Empty 1990 K75S (ABS) Replacement discs. Thu Nov 07, 2019 3:13 pm

mike d

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Hi All,


I've just been asked about the possibility of replacing the worn front discs on a 1990 K75S (ABS), and unfortunately have not come across the proposed solution. 
Note this is to replace just the disc portion, so mounting replacements on the original rotor.

The details I have are:


Bike has done c.90k miles & My Brake discs are fairly worn & a bit "wobbly". I'm aware Motorworks list various new discs, but all are a lot of money & I recently noticed what I think is a fairly new product by "We- Moto". They are just the Brake disc "ring", plus a load of small fittings & the description says that you "grind & Punch out the existing rivets", holding your existing disc "ring" to the centre aluminium bell, and screw together the assortment of "bobbins" & the supplied "ring", to make a floating disc. Cost £77 per side.
 
Have you heard of these, any opinions / feedback??
 
Specifically;
1/ Do we know what diameter are my existing rivets?
                     We- moto Photo is very small, but it looks like the  supplied screws are M5, which would be a lot weaker than a 5mm factory Brembo rivet me thinks.
 
2/ Mine bike is all together at present & the Rivet heads both sides are quite small & there doesn't look to be  that much room for bolt heads / Nuts, c/f the fork legs, or Calipers.
 
3/ Would be impossible to get bolt in behind the ABS ring, so would have to have the NUT that side, unless it is  possible to remove the ABS ring from the R/H disc, which I've never tried & doubt is possible.......


Anyone used this solution before?


Thanks in advance.


Mike

    

Snod Blatter

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Have you got a link? I can't see these anywhere on Wemoto.

People have been bolting new brake discs to the old carriers for a long time but I've never heard of a bolt on semi-floating dealy, no idea how that would work scratch


__________________________________________________
1989 K100RS SE ABS 8v  VIN: 0149214
Others: 1.5 x CBX250RS-E, '94 CB250, '95 TRX850, '16 Z250SL, '01 R1100GS
http://justbikethings.blogspot.co.uk/
    


Ringfad

Ringfad
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Might this be an option (Front and Back discs are the same size on a K75 )

https://www.ebay.co.uk/itm/Brake-Disc-Rear-BMW-K100-82-90/143198217282

I have used one of these on the rear of my K1100RS and it works well. 
You need to remove ABS ring , grind out rivets, I used m5 bolts when fitting disc and then replace ABS ring.


__________________________________________________
1990 K75S (ABS) Replacement discs. Ir-log10

 ;BMW; K1 Black 1993 60K Km     ;BMW;  K1100RS Black 1996       ;BMW; K1 Blue 1990 25K Miles

 ;BMW; K1200RS Red
    

92KK 84WW Olaf

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I must admit I looked at doing this too but in the end decided new discs were less hassle, disc change is really fast. Adding the cost of the new fixings took a huge chunk out of the saving and whats not apparent is the risk of the new ones being out of true if it doesn't go together perfectly lined up. That risk doesn't arise with floating discs.


__________________________________________________
1992 K100LT 0193214 Bertha Blue 101,000 miles
1984 K100RT 0022575 Brutus Baja Red 578 bought 36,000 now 89,150 miles
1997 K1100LT 0188024 Wotan Mystic Red 689 58,645 now 106,950 miles Deceased.
1983 K100RS 0011157 Fricka 606 Alaska Blue 29,495 miles Damn K Pox Its a Bat outta Hell Now 58,200 miles. 
1996 K1100LT 0233004 Lohengrin Mystic Red 38,000 miles currently 51,800 miles.
1983 K100RS 0004449 Odette R100 colours 58,000 miles. Sprint fairing now 63,390 miles

Past:
1968 Yamaha 80 YG1
1971 Yamaha 125 YAS-1
1968 Honda 125 SS
1970 Honda CD 175
1973 Honda CB500-4
Honda CX 500
    

Dai

Dai
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M6 button-head (dome head) A2-grade Allen bolts do the job. Both of my discs are held on by these.

http://www.ebaystores.co.uk/Kays-Fasteners/Button-Heads-A2-Stainless-/_i.html?_nkw=m6+stainless+steel+dome+head&_fsub=2275953012&_sid=112644402&_trksid=p4634.c0.m322

I've forgotten the length but I'm pretty sure I used 12mm. Domes to the outside (no washers), nuts on the inside. I also used nylock nuts with a dab of Loctite nutlock. Don't forget, the bolts are doing very little work in stopping the discs from rotating when you hit the brakes. Most of the work is done by friction/stiction between the disc and the carrier.

[Edit] Nearly 80,000 miles now with no problems but the discs are starting to look a bit worn...


__________________________________________________
1983 K100 naked upgraded to K100LT spec after spending time as an RS and an RT
1987 K100RT
Others...
1978 Moto Guzzi 850-T3, 1979 Moto Guzzi 850-T3 California,1993 Moto Guzzi 1100ie California
2020 Royal Enfield Bullet 500
    

92KK 84WW Olaf

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Don't forget, the bolts are doing very little work in stopping the discs from rotating when you hit the brakes. Most of the work is done by friction/stiction between the disc and the carrier.


Its exactly the same as working with structural steel, which is why getting the bolts right is so important.


__________________________________________________
1992 K100LT 0193214 Bertha Blue 101,000 miles
1984 K100RT 0022575 Brutus Baja Red 578 bought 36,000 now 89,150 miles
1997 K1100LT 0188024 Wotan Mystic Red 689 58,645 now 106,950 miles Deceased.
1983 K100RS 0011157 Fricka 606 Alaska Blue 29,495 miles Damn K Pox Its a Bat outta Hell Now 58,200 miles. 
1996 K1100LT 0233004 Lohengrin Mystic Red 38,000 miles currently 51,800 miles.
1983 K100RS 0004449 Odette R100 colours 58,000 miles. Sprint fairing now 63,390 miles

Past:
1968 Yamaha 80 YG1
1971 Yamaha 125 YAS-1
1968 Honda 125 SS
1970 Honda CD 175
1973 Honda CB500-4
Honda CX 500
    

8Back to top Go down   1990 K75S (ABS) Replacement discs. Empty Re: 1990 K75S (ABS) Replacement discs. Sat Nov 09, 2019 11:27 am

Snod Blatter

Snod Blatter
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These are just the normal bolt-on rotor replacement, no fancy floating..?


__________________________________________________
1989 K100RS SE ABS 8v  VIN: 0149214
Others: 1.5 x CBX250RS-E, '94 CB250, '95 TRX850, '16 Z250SL, '01 R1100GS
http://justbikethings.blogspot.co.uk/
    

mike d

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I forwarded the responses and a link to this site, but at the moment the chap who made the enquiry is looking at the offerings from M&P (in the UK).

I'll post when he responds again.

Mike

    

10Back to top Go down   1990 K75S (ABS) Replacement discs. Empty Re: 1990 K75S (ABS) Replacement discs. Sat Nov 09, 2019 2:55 pm

volador

volador
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Have you compared $$ with Tills.de

https://www.tills.de/bmw-k75-67/bmw-k75xx-133/


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1984 K100RS  1991 K100RS  Reap The Wild Wind... Ever Commute Is An Adventure
    

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