Disc movement an issue?

[ian505050]

I bought a a bike a few weeks ago and thought the head bearing had gone because when i was holding the front brake rocking the bike backward and forward it made a knocking noise.

After closer inspection the knocking noise seems to be coming from the brake disc. The outer part of the brake disc seems to have movement against the part of the brake disc that attaches to the hub.

Its definitely not the case that the brake disc bolts are loose or there is free play between the disc and the bolts.

Its a little hard to explain so i have a quick video below to explain. Do i need to replace the brake disc as it is straight and has plenty of life left? Any advise is appreciated.

https://www.youtube.com/watch?v=2Sn8d99nsZ4&feature=youtu.be

[Howling TerrorOutOfOffice]

Not excessive movement for a fully floating disc.
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[69chris]

dunno how much play is allowed/advised on floating type discs but yours wouldnt bother me, my old blade discs were alot worse than that

[ian505050]

[Pete.]

I agree it's not excessive. Seen a lot worse.
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a.k.a 'Geri'

132.9mph off and walked away. Gear is good, gear is good, gear is very very good

[Kickstart]

Hi

Full floaters can be a lot more than that (most bikes have semi floating disks with very little play), and my Bimota certainly has more.

On the Bimota forum a guy had his bike fail the MOT for play in the disk, until he took his other Bimota down which had done about 500 miles from new and had the same amount of play.

All the best

Keith
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[Howling TerrorOutOfOffice]

Maybe your other bikes had semi-floating discs, they hardly move unless totally clean and tapped with the wooden handle of a hammer.

Speaking to Kickstart (Workshop dude) about this, I seem to remember him saying the disc will wear out long before the carrier would...I'd been surprised by the amount of disc movement on his Bimota YB?
____________________
Diabolical homemade music Bandcamp and Soundcloud
Singer songwriter, Artist and allround good bloke Listen to Andrew Susan Johnston here
The Harry Turner Project

[Howling TerrorOutOfOffice]

HOLY FUCK!
____________________
Diabolical homemade music Bandcamp and Soundcloud
Singer songwriter, Artist and allround good bloke Listen to Andrew Susan Johnston here
The Harry Turner Project

[ian505050]

Thanks for the advise. I had the feeling it was an MOT fail before i posted this question.

[Ed Case]

I had a Laverda triple with 300mm Brembo full floaters that had a damn' sight more slop than that. I doubt that there would be a safety issue there but that depends on the MOT tester, if he had a bike like yours in a couple of days ago without that movement he might well get arsey and fail it.

[sprintster]

I've got a Sprint ST that's got loads of play on one side and none on the other.It's been like that for about 3 years now and it's never been mentioned in an MOT.As it's only my commuter bike I just put up with it,it's only noticeable at low speeds and doesn't affect overall braking.

[Fizzer Thou]

The 'Braking' front disc on my KTM enduro has similar amounts of movement and has never been a problem with my MoT tester

https://i666.photobucket.com/albums/vv23/WiNot_Rhencullen/Dirt%20bikes/20090726_3.jpg

Talon Engineering are importers for these discs so if you have any problems I would ask them for their advice
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Just talk bikes.What else is there?

Always have a 'Plan B'

[Walloper]

https://www.biketorqueracing.co.uk/btr-tech-station/btr-tech-station-brake-systems/brake-discs/fixed-and-floating-brake-discs
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