K11 Owners Group

Off the grid · Posted: Sat Jun 16, 2007 9:32 am Post subject: Bobbins and such.

1. Can anyone point me to a website that sells BMW or compatible (quality-wise) replacement bobbins for my 93 LT?

2. My mechanic said that I have a few mm of play forwards and backwards as well as laterally, plus I am hearing some strange noises from them. Shocked

My que to replace?

3. Whats the best way to replace them? Front wheel off? Rotors off? Replace one at a time or dissasemble all and start fresh?

4. Should I rotate/flip the rotors?

Different topic:

Other than a pipe, what can I do to make my K faster? Cool

Thanks in advance

-Dave
_________________
Bane of your existence since July 2006
2007 Triumph Tiger ABS. "Sabertooth"
2009 Husqvarna TE610. "The dirty Italian mistress"

Tim (Midland Section) · Posted: Sat Jun 16, 2007 9:55 am Post subject:

Try MotoBins in the UK £17 ($34) ish + postage per rotor. Bits are Brembo upgrade. Instructions to fit, the way I did it follow:-

I have a 56,000 mile bike, which developed a rattle from the front whilst manoeuvring.
It was found to emanate from the front discs, which although described as “floating”, I was told that they shouldn’t float radially. After talking with my favourite supplier, we decided that the likely cause was worn disc bobbins, a known failing. There are improved ones available from the East of England.
One front disc was repaired in just over an hour, using the following method, which
assumes that the rider has some mechanical aptitude (usual disclaimers apply): -
1) Jack under the sump, to allow the wheel to rotate.
2) Assemble: - copper grease, lead lamp, short luggage bungee, small hammer,
8" terminal screwdriver, 8" x 1/4" screwdriver, rag, solvent, beer, beer crate & cushion.
3) Using bungee through the wheel, hang the lead lamp to illuminate the inside of the disc.
4) Place cushion on crate, put crate in front of wheel & sit on cushion.
5) Using terminal driver as a drift, with hammer, tap the first circlip off.
6) Remove all 3 bits & keep separate from new ones.
7) Lightly grease bobbin, inside of disc where the washer will go & the ends
of the circlip.
Cool

Fit the bobbin & the washer (check instructions for correct orientation), ensuring that the washer & bobbin are concentric, then push the terminal driver into the circlip slot to hold the washer in position.
9) If you have aligned correctly in step 8, then the circlip will slide into full location, just by pushing the back of the circlip with the 1/4" screwdriver or at most lightly tapping the clip firmly home. If the clip doesn't go into the slot, try compressing the washer with the screwdriver whilst pushing circlip with a finger.
10) Ensure clip has fully seated, repeat 11 more times. Wiping the disc with a solvent soaked rag as you rotate the wheel, to remove any grease, which may have gone astray before it gets onto the pads.
11) Drink beer.
HTH
_________________
Regards Tim,

Grey haired riders don't get that way by pure luck
1996 Guzzi Cali3 LAPD
1972 750 Commando
G6HRN
#485

John Clauss · Posted: Sat Jun 16, 2007 12:50 pm Post subject:

I will add a couple of hints to the excellent reply above.

I found it easier to not jack the bike, but instead let the weight on the front end hold the wheel still while I worked. Rotating the wheel was just a matter of lifting on the fairing a bit.

Take your time, if it doesn't fit do not force it.

Order the parts from a BMW dealer. They are not very expensive, should be around $75 for the lot.

There is a pictoral of how to do this in this months BMWMOA magazine, maybe its on the website.

Have fun.
_________________
1997 K1100LT
1975 R75/6

It will bring you so close to nausea, it will make you sick! - Big Al

Phil Marvin · Posted: Sat Jun 16, 2007 12:58 pm Post subject:

Hi, Dave,
Tim's method is fine as is his parts source (MotoBins), but there are a few caveats.
1. The price is right (GBP 17 is a bit less than $34). Double this (2 rotors) and add shipping and your credit card fee for foreign exchange (usually 3%) and you're probably looking at around $80 - a bargain. HOWEVER, if I remember correctly, the MotoBins parts are steel and BMW's parts are alumin(i)um. The BMW bobbins are sacrificed so the disc carrier wears less.
2. The disc carriers DO wear, especially the holes in which the "spring" bobbins ride. There are 3 of these per rotor. When you change the bobbins, move all the "spring" bobbins one hole so the springs have a relatively fresh hole to wear against! The old locations of the "spring" bobbins are filled with fresh plain bobbins. If you don't do this, the new bobbins will wear out prematurely. Don't ask me how I know!!
3. A real cheapskate MIGHT(?) get by only replacing the spring bobbins.
4. Another USA BMW dealer has a fiche on the web (Hammersly?) The last time I checked bobbin prices, they were by far the cheapest (not counting MotoBins). They may still be; they may not be, but with BMW parts prices as they are, it pays to check.
Ride Safe,
_________________
Ride Safe,
Phil Marvin in El Paso, TX
'94 K75A/3
'95 K75RTP

dave n · Posted: Sat Jun 16, 2007 4:01 pm Post subject:

Lightly grease bobbin, inside of disc where the washer will go & the ends

Can't agree with this part - any grease here will mix with the road grit and make a grinding paste (think valve lapping compound) and hasten wear.
And possibly contaminate your hard working brake pads.
_________________
Dave Norris KOG 248
1999 Cagiva Gran Canyon
1993 K1100LT w/Hannigan sidecar
2008 Suzuki DR650

bmwmick · Posted: Sun Jun 17, 2007 1:06 pm Post subject: Re: Bobbins and such.

old guy old bike · Posted: Fri Sep 14, 2007 11:48 am Post subject:

Ok, this is coming up real quick on my to do list. BMW really likes their aluminum bobbins after the last round of price increases. The steel bobbins can still be purchased from Motobins in the $90 range for both discs. This more than cuts the cost of the job in half. The question I have is how bad do the steel buttons eat up the hub and discs? I don't want to save $100 on bobbins and then have to spend 5 times that down the road.
Thanks,
Jeff
_________________
1993 K1100LT
2003 K1200GT Gone but not forgotten
2014 Victory Crossraods

bmwmick · Posted: Fri Sep 14, 2007 12:40 pm Post subject:

old guy old bike · Posted: Fri Sep 14, 2007 1:04 pm Post subject:

Thanks Mick. I was basing my figures on what my local BMW dealer gave me. I came out over $200 for both rotors. It did include new clips and washers though. I really don't see the clips and washers as a high wear item. They may be just telling me to replace everything because they want to sell me everything. Would they do that!
_________________
1993 K1100LT
2003 K1200GT Gone but not forgotten
2014 Victory Crossraods

Flying Duck · Posted: Fri Sep 14, 2007 1:14 pm Post subject:

bmwmick · Posted: Fri Sep 14, 2007 1:44 pm Post subject:

nickmakwell · Brick Rider Joined: 12 Aug 2006 Posts: 30

Im doing this job right now - bought the kit from my local BMW guy - $107 per disc OUCH!!!

anyway, having trouble putting the new spring bobbin pins in - should I use a little grease and/or try compressing the spring a little with some pointy pliers to get it to fit?

the new ones wont go all the way in past the carrier....

nickmakwell · Brick Rider Joined: 12 Aug 2006 Posts: 30

oh the rest take no time at all - easy peasy.

ill go do the other disc first and then come back and try all 6 spring bobbins.

bmwmick · Posted: Sat Sep 15, 2007 11:28 pm Post subject:

wera32 · Posted: Sun Sep 16, 2007 8:32 am Post subject:

Sorry I'm too late to help Dave but when I needed to do this job I bought two used rotor assemblies for $150. They were almost like new. I think they came from Cycles Recycled but I'd have to check to be sure. My originals were almost to the wear limit anyway. It's good to have options.
_________________
Paul - '93 K11/12RS (sold), 2002 R1100S BCP and '03 RC51 KOG 29

Frank · Posted: Sun Sep 16, 2007 2:51 pm Post subject:

G'day Guys

I just replaced my bobbins in the last month. Cost me $A190 from Munich Motorcycles in Perth.

Job took about 90 minutes or so, finding jack, removing wheel (getting old can't bend down anymore).

My bobbins looked square when I pulled them out. I had no trouble replacing the spring ones.

Best money that I have spent on the bike, now I have confidence in the ABS system and no rattles from the front when braking.
_________________
Ride safe

Frank
Gold Coast Australia

BMW 1997 K1100LT - White

Ulysses Member 33144
StruggleTown Tourers

Gary Bennett · Posted: Mon Sep 17, 2007 6:52 am Post subject:

Frank,

The bobbins from Munich M/C, are they aluminium or steel? OEM or Aftermarket?
_________________
Gary
'94 K1100RS

Frank · Posted: Tue Sep 18, 2007 3:10 am Post subject:

G'day Garry

Sorry but I can't remember if they where alum or steel, hang on second I will go and check.

OK, they are alum, put magnet on them and the slide around to the steel disc.

The bobbins arrived in a clear plastic bag with no markings, so not sure if they are BMW or aftermarket.

How is the exhaust on your bike? Mine broke at No4 header and I had it redone at Motorcycles Exhaust Specialists in Slacks creek. They did it aka K100 slip-on style. (Just asking as I am following a thread on the Internet BMW Riders Tech mailing list)
_________________
Ride safe

Frank
Gold Coast Australia

BMW 1997 K1100LT - White

Ulysses Member 33144
StruggleTown Tourers

Gary Bennett · Posted: Tue Sep 18, 2007 6:42 am Post subject:

Frank,

The bobbins are probably BMW parts that Munich M/C source directly from the original manufacturer.
My exhuast has never been touched and the bike has done 155,000km. If it ever did crack I was going to get the same guys to do what you got done. As a point of interest, did you know that the guy that owns the business (Noel) is a Kiwi and designed and built the exhuast for the NZ made "Britton" race bike back in the 80's I think it was.
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Gary
'94 K1100RS

Frank · Posted: Wed Sep 19, 2007 2:23 am Post subject:

Garry

No troubles at all with the exhaust. Does not leak or sound too bad. makes for easy fitment.

Noel did a good job and i didn't know about the Brittion connection. Thanks
_________________
Ride safe

Frank
Gold Coast Australia

BMW 1997 K1100LT - White

Ulysses Member 33144
StruggleTown Tourers