Play in front brake rotor?

I know the front rotor floats and it's normal to have side to side play in it. However, I've noticed mine has front to back play. In other words, if I hold my front brake I can rock the bike back and forth slightly and can brake disc moving back and forth on its carrier. Right now there's probably about 2mm of total movement.

How much play, if any, is normal?

This is for a DRZ-SM.

Edited by bad mechanic

I know the front rotor floats and it's normal to have side to side play in it. However, I've noticed mine has front to back play. In other words, if I hold my front brake I can rock the bike back and forth slightly and can brake disc moving back and forth on its carrier. Right now there's probably about 2mm of total movement.

How much play, if any, is normal?

By "rotor" I think you mean caliper, because as far as I know the OE rotor is solid (neither a semi or fully-floating design). The caliper is free to slide laterally (perpendicular to the rotor face) because of its single-sided piston design (floating caliper).

However if you have an aftermarket rotor, then it could be a floating rotor. 2 mm sounds like a lot of movement, I’m surprised the buttons holding the brake rotor to the carrier don’t fall out.

Mash down on the rivets, should tighten back up.

By "rotor" I think you mean caliper, because as far as I know the OE rotor is solid (neither a semi or fully-floating design). The caliper is free to slide laterally (perpendicular to the rotor face) because of its single-sided piston design (floating caliper).

However if you have an aftermarket rotor, then it could be a floating rotor. 2 mm sounds like a lot of movement, I’m surprised the buttons holding the brake rotor to the carrier don’t fall out.

I mean the rotor. The OE rotor on the SM is floating.

2mm ain't nothing to worry about

The old GSXR -WT's were reknowned for it, and they would wear so bad the rotor would eventually roll up onto carrier

Its the soft Aluminium carrier that wears away causing the disc buttons to be loose

Just keep an eye on it and sort it out when it gets bad

2mm ain't nothing to worry about

The old GSXR -WT's were reknowned for it, and they would wear so bad the rotor would eventually roll up onto carrier

Its the soft Aluminium carrier that wears away causing the disc buttons to be loose

Just keep an eye on it and sort it out when it gets bad

So...what's bad?

So...what's bad?

I'm guessing when the rotor falls off :p

My full floater has had about 2mm play in it for over 6 months now that I am aware of (could be longer but I noticed 6 months ago), I have been meaning to replace it but haven't done so yet. I can actually move mine by hand without using the front brake. In six months it hasn't gotten any worse. That said I am not heavy on the front brakes very often as I ride pretty much 100% road. Keep an eye on it and replace it as soon as you can afford to....

So...what's bad?

You'll know, coz the disc will be slopping about all over the place and making a right old racket

seriously though, there's no magic figure of when its 'bad'

keep an eye on it, the disc is in no danger of coming off' - I'd say when its gets to about 5-6mm of play then find a replacement

'mashing on the rivets' like suggested above will do nothing as the excess clearance is radial

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