[scottishmark]

Alright folks,

after riding at the weekend I noticed (by chance really) that one of my rotors has lost a good amount of its metal. Haven't measured it yet, but it's probably approaching half original thickness.

so the question really is when should rotors be replaced? cant remember ever seeing any guideline for this - ride until it explodes, 0.5mm?, 0.001mm?

Cheers,
Mark

 

[mellow_sparky]

I have a newer Hayes service manual and it states the min. thickness for Hayes rotors to be 1.52mm.

 

[Mr Jones]

Most rotors, unless they're ancient or aftermarket, will have a minimum thickness marking on it.

 

[rockofullr]

one of my rotors has lost a good amount of its metal. Haven't measured it yet, but it's probably approaching half original thickness.

It's time.

 

[jonKranked]

if its lost that much metal, chances are your caliper is out of alignment or your brake pads are shot too - and by shot I mean there is no compound left on them. The only time I've ever seen rotors get worn down like that when there is substantial metal on metal grinding.

 

[scottishmark]

never had any metal on metal with these brakes, just around 4 years all year round DH use. haven't checked for a profile that would indicate poor alignment, but i would've thought that being Avid's the tri-align would've reduced the chances of that occuring?

i'll check for markings and get the micrometer/verniers on it too

 

[jonKranked]

dang, 4 years of dh use? the longest I ever got out of one set of rotors for DH was a single season, before wrecking and bending them. whoops!

 

[scottishmark]

so this isn't good then? ???

 

[IH8Rice]

dang, 4 years of dh use? the longest I ever got out of one set of rotors for DH was a single season, before wrecking and bending them. whoops!

thats pretty bad.

so this isn't good then? ???

my avid's are 1.87mm. i cant see if they are marked since they are muddy, but my Hayes rotors have a minimum thickness of 1.52mm written on them.

 

[oldfart]

Most rotors, unless they're ancient or aftermarket, will have a minimum thickness marking on it.

They do? Never noticed one myself. What should I look for? A dimple like on some rims or??? Or do mean they actually engrave the min thickness number on them somewhere? I guess that might be a good enough reason to purchase a pair of calipers. Can't have too many tools can you.

 

[Mr Jones]

They do? Never noticed one myself. What should I look for? A dimple like on some rims or??? Or do mean they actually engrave the min thickness number on them somewhere? I guess that might be a good enough reason to purchase a pair of calipers. Can't have too many tools can you.

My avid roundagon's have the min thickness etched next to the part number

My hayes and my shimano rotors have the min thickness etched near the bolt holes.... and true, you can never have too many tools

 

[BIGHITR]

And I just so happen to have a BRAND NEW SET of six inch hayes rotors for sale... heh heh heh...

 

[scottishmark]

make them 2 inches bigger and get back to me

 

[BikeFan84]

2011 G3 avid rotors, looked all over no minimum on them anywhere, checked 5 185s and 6 203s, nowhere to be found. I replace my rotors every year though, and have a stock pile of new ones laying around (way easier $$$ to do with Avids, than hope stuff)