2003 R1150RS Warped Brake Rotors?

[TimBoulay]

Aloha, I have a new to me 2003 R1150RS with 42000 miles and noticed that the front rotors seem warped, when applying the hand brake. The bike has ABS delete, and was wondering any tips, tricks that I need to know prior to installing new rotors and brake pads.

[dirtrider]

54 minutes ago, TimBoulay said:

Aloha, I have a new to me 2003 R1150RS with 42000 miles and noticed that the front rotors seem warped, when applying the hand brake. The bike has ABS delete, and was wondering any tips, tricks that I need to know prior to installing new rotors and brake pads.

Evening TimBoulay

 

What makes you think the front brake rotors are warped? Those rotors are semi free-floating so warpage typically isn't an issue. 

 

If you are getting front brake pulsation then most likely your issue is not warped rotors but instead stained or oxidized spots on the brake rotors that changes the braking friction every time one of those stained spots passes between the brake pads.  

 

If you have brake pulsation can you feel it in the hand lever?  (if so then possibly warped rotors but the warping needs to real bad as the free-floating will remove most of it). It could also have rotor thickness variation, THAT will really cause brake pulsation with  a matching  brake lever pulse or kick as every thick spot passes through the brake pads.  

 

But if you have front brake pulsation and the hand lever is isn't pulsing & kicking in your hand then more than  likely you have stained or oxidized spots on the rotors.

 

That staining or oxidation usually happens when the bike is stored with wet brakes, or stored in a damp or high humidity area & isn't moved for long periods. (the brake pads actually corrode the rotors where the pads are), unfortunately you usually can't see or feel that staining but it is just enough to change the rotor friction in those stained areas.

 

Rotor staining is removable but it sure isn't easy to do without a lot of work.  

 

 

 

[TimBoulay]

Well I will just replace the rotors as planned. I just want to ensure that there wasn't any other tips/issues that I might need to be aware of, since the ABS delete.

 

[Hosstage]

Heat the bolts to break the Loctite?

[King Herald]

7 hours ago, Hosstage said:

Heat the bolts to break the Loctite?

 

I had to change my rear disc at 100,000 miles, due to extreme wear. The bolts have been in there since 1997, through 20+ salty English winters, and I full expected each one to break. But a little gentle heat with a blow torch and steady leverage with a good quality, well fitting Torx drive and they all came out fairly easily. 

 

Front discs are still in perfect condition, no discernible wear, though I did replace the aluminium bobbins with stainless a few years ago. 

[King Herald]

13 hours ago, TimBoulay said:

Aloha, I have a new to me 2003 R1150RS with 42000 miles and noticed that the front rotors seem warped, when applying the hand brake. The bike has ABS delete, and was wondering any tips, tricks that I need to know prior to installing new rotors and brake pads.

 

I'd be inclined to spin the wheel with the bike on the stand and have a look, see if they are indeed warped, or as DR says there might be some staining on them from standing.

 

Check the condition of the bobbins too, if your model has them, as mine gave a strange feel through the brake lever, and clicky sound, when they were on their last legs. 

[dirtrider]

12 hours ago, TimBoulay said:

Well I will just replace the rotors as planned. I just want to ensure that there wasn't any other tips/issues that I might need to be aware of, since the ABS delete.

 

Morning TimBoulay

 

A couple of things to pay attention to. 

 

With no ABS then you probably don't now have a front wheel speed sensor but if you do then remove it (& spacer shims) before removing the wheel. (you can leave it off)

 

You will probably have to push the caliper pistons back into their caliper bores to get the wheel off so that will push brake fluid back into the master cylinder reservoir, if your reservoir is now full that can push fluid out past the cover gasket & onto your painted surfaces (brake fluid is a great paint remover). Either lower the fluid level or place some plastic garbage bags under the master cylinder to protect your paint.  

 

As Hosstage said, heat the rotor bolts to remove, if you don't then you risk tearing the soft alloy bolt threads out of the alloy wheel.

 

The factory torque on the front rotor bolts is 21 Nm but if you get aftermarket brake rotors then use their install & torque procedure. The factory bolts have a Ny-Lock type locking compound on them, the manual calls for using  Loctite 2701 at reassembly (difficult to get) so most just use LockTite 242 (blue).The 242 takes a lot longer to cure when used on an alloy wheel & stainless  bolts but it will eventually cure.

 

If you still have the toothed ABS tone ring you can remove that as it is no longer needed.  

 

 

[1150RSSSS]

Joining this thread a little late but thought I'd share a related experience. I noticed pulsing on my brakes shortly after removing the ABS, probably more noticeable given the better feel you get when you go to manual. After a lot of measuring and inspecting I noticed that one spacer was missing, the one between the disc and the wheel, which was enough to throw the disc out of plane and create irregular wear. Don't know why it was missing (used underwear?), but consistent with what I've read here that these don't tend to warp from normal use (just human installation error).