I was wondering what the runout limits are for a solidly mounted disc with Brembo 08 calipers?
I currently have measured near the outside edge of the disc of 0.08 mm (0.0031") runout.
Disc Runout Limits
- BevHevSteve
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I don;t know what the limits are, but can you feel a pulse when you apply the brakes? If yes then do something about them. If no then don;t worry about it. That is a pretty small amount you have.........
Steve Allen (925)798-BEVL[2385] Ride'm, Don't Hide'm
Ducati/Euro Spares -> https://Store.BevelHeaven.com
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- Cucciolo - the Lil Pup
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Disc Runout Limits
Hi there,
I THOUGHT that I once saw that something's printed in that thin side of the disc! Just checked this, but could't find it anymore!
(May'be 'cause of corrosion!)
Take a close look there, with good light.
Regards,
Ernst
I THOUGHT that I once saw that something's printed in that thin side of the disc! Just checked this, but could't find it anymore!
(May'be 'cause of corrosion!)
Take a close look there, with good light.
Regards,
Ernst
Bend over and smell my Conti vapour!
Pulsing brakes
Hi, I read the above thread, and I have a strong pulsing in my brakes - 1979 900SS with cast iron disks. Do these things warp, or does this mean I need to get new disks - could I get them reground flat?
Thanks,
DaveG
Thanks,
DaveG
Pulsing is often caused by a patch of corrosion where a damp pad has sat, the worst thing is to leave the bike laid up after road salt contamination. With a good long run and heavy use it usually fades out.Badly corroded discs cause heat fade and loss of all braking if decending mountains ,especially with old fluid,( the corroded disc does not take the heat away from the pad). I learnt this the hard way---twice!!.
- BevHevSteve
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easy enough to see if the disk has warped, just left the front and give the wheel a spin. Hold a pencil against the fork with the point at the disk...
Steve Allen (925)798-BEVL[2385] Ride'm, Don't Hide'm
Ducati/Euro Spares -> https://Store.BevelHeaven.com
Yes that was the first thing I did - I reckon (just holding a screwdriver up against the disk) that there is about 0.25 mms run out. And then I started thinking that this shouldn't make it pulse anyway, as the pistons should move to compensate for any slight warp.
Is 0.25mms too much? Can I get the disk turned flat or is that not practical?
Thanks,
DaveG
Is 0.25mms too much? Can I get the disk turned flat or is that not practical?
Thanks,
DaveG
If you can find a machine shop that can grind the disc to true it you will probably have enough meat to do it. Using a lathe would be a second choice but it can be difficult because of vibration/chattering giving a poor surface.The info stamped on the edge of the rotor is the mininum thickness spec. Being slightly under that spec. would probably be ok unless you use the brakes really hard alot.When you remount the rotors make sure the mounting flange areas are clean and smooth along with torqueing the bolts evenly.
Please read this first:
http://www.stoptech.com/tech_info/wp_wa ... disk.shtml
http://www.stoptech.com/tech_info/wp_wa ... disk.shtml
Sorry to come back to this again, but I removed the disks, and they are definately warped i.e. bent on both sides (inside and out), so I don't see how I can get them ground down, I think I need to replace them.
Looking around the web, there seems to be an EBC replacement disk setup, and I see them for sale on the BH web shop. I have spoked rims, and the disks, really make up the hub, and also provide the speedo fixing point - does the right hand EBC disk allow the speedo to fit, or is some modification required?
Thanks,
DaveG
Looking around the web, there seems to be an EBC replacement disk setup, and I see them for sale on the BH web shop. I have spoked rims, and the disks, really make up the hub, and also provide the speedo fixing point - does the right hand EBC disk allow the speedo to fit, or is some modification required?
Thanks,
DaveG
- BevHevSteve
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Dave - the EBC disks fit straight on - no problems.
Steve Allen (925)798-BEVL[2385] Ride'm, Don't Hide'm
Ducati/Euro Spares -> https://Store.BevelHeaven.com
Hi Steve,
So the bit that I have drawn an arrow to comes off seperate from the disk?
http://proclassicracinginfrance.blogspo ... cture.html
Thanks,
Dave
So the bit that I have drawn an arrow to comes off seperate from the disk?
http://proclassicracinginfrance.blogspo ... cture.html
Thanks,
Dave
- BevHevSteve
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You are pointing to the bearing holder, that is not part of the brake. It is part of the hub.
I would put money on your calipers and/or master cylinder needing rebuild for being the reason WHY you have overheated your disks and warped them
Steve Allen (925)798-BEVL[2385] Ride'm, Don't Hide'm
Ducati/Euro Spares -> https://Store.BevelHeaven.com