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Discussion Starter · #1 ·
Tap on front brake and it feels like fork legs are loose. checked stering bearing no play. Have someone fold front brake and pull back and froth on bottom of fork at the axle and it feels loose in lower legs. Checked pinch bolts everything tight
 

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Mines the same, everthing checked out ok but when pushing bike around i can feel a slight knock in the front end. maybe its discs / pads moving in calipers or something but no play in head bearings.
 

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First thing I felt when I checked out an 06 in a dealer showroom. With the front brake on and just feeling the front suspension there was a slight movement like fork stiction or loose steering head bearings. I couldn't find the source but the sales guy eventually suggested floating brake rotors (which I know nothing about). I guess if lateral movement of the rotor is allowed then there has to be a little fore and aft clearance between rotor bushings, mounts and rotor.

Anybody with info on floating brake rotors ?
 

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The floating rotor.
Standard brake rotors are cast in a single piece which bolts directly to the wheel or drive plate. If the mounting surface of your wheel or drive plate isn't perfectly flat, you'll get vibration at speed. Floating rotors are typically cast in two pieces - the rotor and the carrier. The carrier is bolted to the wheel and the rotor is attached to the carrier using float buttons. The other method of floating a brake rotor is to have the rotor bolted directly to the wheel itself without a carrier, but the bolts have float buttons built into them.

These buttons allow the brake rotor some freedom to move laterally, but restrict the angular and rotational movement as if they were bolted directly to the wheel. This slight lateral motion which can be less than 0.03mm, is just enough to prevent vibration in the brake system. Because the calipers are mounted solidly, and warping or misalignment in the wheel or brake rotor mounting face can be compensated for because the rotor will "float" laterally on the float buttons. This side-to-side vibration is separated from the carrier by the float buttons themselves, so none of the resulting motion is transferred into the suspension or steering. Clever eh? The rendering below shows an extreme close-up of the brake disc shown above. I've rendered the components slightly transparent so you can see what's going on.

Full article and pictures at: http://www.carbibles.com/brake_bible.html
 

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Looks like lots of us have this and head bearings check out ok, so its fairly comforting knowing your bike is not the only one, as others suggest maybe rotors / stiction, either way it sounds like all is well, handling feels fine so it seems to be nothing to worry about.
 
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