1150 front disc help needed

[PIGGLET]

Recently fitted a new set of front discs with new bobbins, washers and bolts. Are 1150 disks of the "floating" variety or are the bobbins I've been supplied with too long
Not noticed it on my other set of wheels before and I don't have access to the bike for a comparison at the mo
Thought I'd better check before I ring the bobbin supplier for a rant
TIA

 

[Carefulkev]

On my 99 1150GS they are the floating type, with wavey profile shim on each bobbin.

 

[Steptoe]

1100/1150/1150ADV, all have fixed discs, none of them float.

If they move, you have a problem.

 

[PIGGLET]

1100/1150/1150ADV, all have fixed discs, none of them float.

If they move, you have a problem.

Nadgers

Sounds like you've got some fettlin to do too kev

Cheers Steptoe

 

[Underwatergoat]

They are sort of fixed. They are held in place by being preloaded by the wave washers. Did you leave them out or reuse the old ones? It's best to use all new fixings.

 

[PIGGLET]

I used all new parts, wavy washers included. The disks are as you say pre-loaded against the hub by the washers but if you grab hold of the disk it can be pulled away from the hub (albeit under tension, it then springs back).

 

[Underwatergoat]

That sounds ok then? Any radial movement? Should be minimal.

 

[Kenny Rodkiss]

how thick

Make sure you have the right bobbins as the R1150gs uses front discs that are 4.5mm thick with fittings to match, Some other models like the R1150R have 5mm thick discs with longer bobbins to match.

 

[Paul Young]

Make sure you have the right bobbins as the R1150gs uses front discs that are 4.5mm thick with fittings to match, Some other models like the R1150R have 5mm thick discs with longer bobbins to match.

That's interesting, Kenny... Why the difference - do you know?

 

[Kenny Rodkiss]

Dunno

It all came to light when I bought some Galfer wavy discs to fit to a set of spare wheels.
Found out when I tried to fit them that the Galfers were '5mm' thick and when bolted on they were solid to the hub without any movement at all as the wavy washers were squashed absolutly solid flat.
That was when I found out that the standard discs are 4.5mm thick and 5mm discs were never going to fit correctly with fittings for a thiner disc.

Then after a bit of investigation it turns out that BMW fit a 5mm disc to some of their road models, don't know why.
Buy some fitting for the 5mm disc I though, but , turns out quality control at galfer had a day off.
One disc was 4.80 thick and the other 5.20. Go figure.

As the movement allowed by the wavy washers is very little any variation in disc thickness at mounting points will give too much or not enough clearence.

Supplier of Galfer discs could not guarantee that discs would be 5mm thick, no more no less.

Bought some second hand BMW discs, both 4.5mm.
Still seeing Galfer discs for sale as a bolt on replacement for R1150 and R1200 gs's, but can't see how as they are the wrong thickness.

 

[Comfy Old Boots]

Make sure you have the right bobbins as the R1150gs uses front discs that are 4.5mm thick with fittings to match, Some other models like the R1150R have 5mm thick discs with longer bobbins to match.

good info for an 850r owner

 

[Comfy Old Boots]

might get bmw to fix my sned rear disc

 

[Steptoe]

Make sure you have the right bobbins as the R1150gs uses front discs that are 4.5mm thick with fittings to match, Some other models like the R1150R have 5mm thick discs with longer bobbins to match.

There are two types of disc used on the GS, some servo brakes have "narrow" brake discs.

 

[Kenny Rodkiss]

There are two types of disc used on the GS, some servo brakes have "narrow" brake discs.

Both my 2001, 1150 gs and my 2006, 1200gsa had the narrow discs but both did not have servo brakes?

Only seems to be R****R models that have a thicker discs.

 

[Steptoe]

Both my 2001, 1150 gs and my 2006, 1200gsa had the narrow discs but both did not have servo brakes?

Only seems to be R****R models that have a thicker discs.

I'm don't mean thickness of the disc, when i say narrow i'm talking about the friction surface/face of the disc)

The 1200GS has "normal" discs , the same as the non servo 1150, they aren't the narrow type i'm talking about.

Only some servo bikes, 1150R, 1150RT 1150Gs have the "narrow" type of discs i'm talking about. They also have very slightly different brake calipers

 

[RiceBurner]

I'm don't mean thickness of the disc, when i say narrow i'm talking about the friction surface/face of the disc)

The 1200GS has "normal" discs , the same as the non servo 1150, they aren't the narrow type i'm talking about.

Only some servo bikes, 1150R, 1150RT 1150Gs have the "narrow" type of discs i'm talking about. They also have very slightly different brake calipers

Would that be the difference between Brembo and Tokico calipers?

 

[Steptoe]

Would that be the difference between Brembo and Tokico calipers?

No - The brembo calipers use the same discs as the 1200GS and the majority of the 1150.

But it is the Tokico bmw calipers that use the "narrow" disc. Not to be confused with the almost identical BMW tokico looking caliper used on the 1200 and 1150 .

I know what i'll do = I've got a bike in today with the narrow discs fitted - I'll take a picture later.

 

[PIGGLET]

Finally got round to torqing up all the bolts on the wheels/disks and comparing the movement of the disks to that of the wheel on the bike. It's exactly the same. I rang motoworks too and they said that there should be a tiny bit of movement (away from the hub, not radial) also so it all looks good. Thanks for all the info and replies