Front break disk bent

[singapura]

Hi fellow Valk riders! I have a technical question: Yesterday my mechanic noticed that my left front break disk is slightly bent. I noticed that when the disk is cold, it makes a faint "whir, whir" sound but have not experienced anything worse like shuddering. Should I replace the disk (or even replace both disks) or can it be straightened? Are there any good after market disks? Thanks for your advice!

[Bighead]

If it were me and i was going to replace one I would do both. There are probably some here say not necessary but that is just me. And I haven't had to replace one so don't know about aftermarket.

[art]

Bring it to a machine shop. If not too bad they can fix it . I'm a retired machinist  an know what I'm talking about.

[Jess from VA]

Except there's very little machining available in a motorcycle brake disk.

Valk disks were very expensive, and people used perfectly fitting 1800 wing disks as cheaper, then the price of valk disks went down.

There is a difference between a bent (hit) and a slightly warped disk. 

It probably will need replaced, and I'd do both (unless the other side is perfectly good) and pads on the bad disk side are probably irregularly worn.  Even if lots of pad is left, you won't get a good contact on a new disk.  EBC disks should have ebc (or any organic) pads.  OE disks need OE (or any organic) pads.

[Punisher]

Except there's very little machining available in a motorcycle brake disk.

Valk disks were very expensive, and people used perfectly fitting 1800 wing disks as cheaper, then the price of valk disks went down.

There is a difference between a bent (hit) and a slightly warped disk. 

It probably will need replaced, and I'd do both (unless the other side is perfectly good) and pads on the bad disk side are probably irregularly worn.  Even if lots of pad is left, you won't get a good contact on a new disk.  EBC disks should have ebc (or any organic) pads.  OE disks need OE (or any organic) pads.

It may not need machining but just pressure applied in the right spot with a Press to realign it, depending on how bad it is out and where.   A proper machine shop can look at it and make that determination.

Also it depends on how worn they are to start with, if close to the wear limit then better to just replace and be done with it.

[gordonv]

Sorry guys, but I gotta say, cough "bull" (no disrespect intended   ). I don't see how the disc could be "damaged" without the owner knowing about an accident that would have caused it. Discs are really tough items.

Unless this is a new to the current owner bike, or there has been a know accident, or maybe over heating on the disc (brake applied going down hill), I can't see this happening. Since new? How did it get through all these years and Honda qty check?

I would first confirm yourself that this disc is what is wrong, not the front rim installed/aligned improperly. I would start by trying to confirm that it is the disc. How to do this? Raise the front wheel off the ground, and spine the wheel. Maybe check the front axle, and see if it is installed all the way in?

[Patrick]

How did you break your brake disc ?  Anyway, I'd recommend replacement. And the retainers are reusable.

[PAVALKER]

Sorry guys, but I gotta say, cough "bull" (no disrespect intended   ). I don't see how the disc could be "damaged" without the owner knowing about an accident that would have caused it. Discs are really tough items.

Unless this is a new to the current owner bike, or there has been a know accident, or maybe over heating on the disc (brake applied going down hill), I can't see this happening. Since new? How did it get through all these years and Honda qty check?

I would first confirm yourself that this disc is what is wrong, not the front rim installed/aligned improperly. I would start by trying to confirm that it is the disc. How to do this? Raise the front wheel off the ground, and spine the wheel. Maybe check the front axle, and see if it is installed all the way in?

I wouldn't be so quick to say, cough "bull", as you gave some good reasons of how it could be bent in your post.  Could very well have happened, either with a previous owner or even the current one.  Maybe he had a tire change and the disc was damaged slightly at that point.    Yea, could very well be the front rim is not aligned properly causing that issue.  Hell, the mechanic that noticed the problem could have caused it as well. 

And.... if it is slightly bent, it could very well be corrected by a machinist.... but depending on how worn they are it might be much better or more cost effective to just get replacement discs.

[Ricky-D]

Well, if you've been riding with it for long and have not noticed any braking problem,

I'd say, continue on!

It evidently isn't serious enough to cause any trouble and will not cause any trouble

with future riding.

The caliper is adaptable to much irregularity in the rotor (disc) as has been revealed.

This is a "no sweat" issue.

***

[Daniel Meyer]

Well, if you've been riding with it for long and have not noticed any braking problem,

I'd say, continue on!

It evidently isn't serious enough to cause any trouble and will not cause any trouble

with future riding.

The caliper is adaptable to much irregularity in the rotor (disc) as has been revealed.

This is a "no sweat" issue.

***

Kind-of agree with Ricky-D...except I'd add...go do some HARD straight-line braking (in dry, controlled conditions). If it shudders at all replace the disks (both sides). You don't want degraded performance when you may need it most... Also inspect VERY closely for damage to the attachment center thingy...where the rivets are.

Otherwise, run 'em to the wear limit and replace 'em then.

[Gryphon Rider]

Kind-of agree with Ricky-D...except I'd add...go do some HARD straight-line braking (in dry, controlled conditions). If it shudders at all replace the disks (both sides). You don't want degraded performance when you may need it most... Also inspect VERY closely for damage to the attachment center thingy...where the rivets are.
Otherwise, run 'em to the wear limit and replace 'em then.

Daniel, I recall that you replaced your discs after letting them wear to considerably thinner than the wear limit.  How thin did they get, and did you notice anything that told you you shouldn't have done that?  One reason I ask is that my understanding is that the compatible Goldwing rotors start out being thinner than the Valk ones, with their wear limits being considerably thinner than the Valk wear limits.

[Daniel Meyer]

Kind-of agree with Ricky-D...except I'd add...go do some HARD straight-line braking (in dry, controlled conditions). If it shudders at all replace the disks (both sides). You don't want degraded performance when you may need it most... Also inspect VERY closely for damage to the attachment center thingy...where the rivets are.
Otherwise, run 'em to the wear limit and replace 'em then.

Daniel, I recall that you replaced your discs after letting them wear to considerably thinner than the wear limit.  How thin did they get, and did you notice anything that told you you shouldn't have done that?  One reason I ask is that my understanding is that the compatible Goldwing rotors start out being thinner than the Valk ones, with their wear limits being considerably thinner than the Valk wear limits.

I'm a cheapskate...and a test pilot...and have a *very* good rapport with my machines...so...yep, I ran 'em way under spec. Let's just say, "considerably".

Once they got down "so far" they started wearing unevenly...grooved a bit. I ran 'em till they didn't feel right...(still plenty of metal) and replaced them then. I get to...test...braking performance pretty much daily in Dallas traffic...

Gold wing rotors will work fine, but now the Valk rotors are actually cheaper. Used to be the other way around, and by one big number.

[saddlesore]

Before getting too excited just jack up the front tire and spin it.  Use a run out gauge to check for any discrepancies.

http://www.harborfreight.com/hand-tools/measuring-tools/1-inch-travel-machinists-dial-indicator-623.html   

[art]

Like I said check with a machine shop. If it is just a little out it can be pressed back into shape within .001 and that is good. I had a bad valk drive shaft that was .036 out and I got it within .001  It can be done. I even made my own Disks for my GW at a price of $200 for four. Now a badly bent disk is scrap and needs to be replaced. A good machinist could do it for about $50 if it isn't too bad.

[salty1]

Before getting too excited just jack up the front tire and spin it.  Use a run out gauge to check for any discrepancies.

http://www.harborfreight.com/hand-tools/measuring-tools/1-inch-travel-machinists-dial-indicator-623.html   

  +1

[Ricky-D]

It is doubtful that the disc is bent.

Usually it is the carrier that bends seeing the carrier is aluminum.

Pretty easy to realign the setup with a little knowledge and patience.

Probably the biggest culprit is from mishandling the wheel, for instance when

changing the tire.

Also, some times the damage comes from forgetting there is a disc lock

being employed on the bike.

***

[Patrick]

This has taken a life of it own.
The real way to check that rotor is to measure it. Install a dial indicator and see what it has to say. If the runout is more than .005", there is a problem. Removing the rotor is easy and may [or not] show a problem. Even a chunk of crap [technical term] lodged under the rotor from inattentive installation can give an impression of a bad rotor.
I assumed we knew we had a 'bent' rotor.

[valk2001]

I purchased a new pair from this ebay seller WXTRACING for $169.00/Pair last fall for the front of my 2001 Interstate.  I have put about 5,000 miles on the pair thus far and they are doing great.  No virbation, smooth stops, showing no wear at all thus far.  I also went back with Honda new pads at the same time as replacing the rotors.

I am in no way affiliated with wxtracing.  These rotors are made in China but sold all over the world and I had a riding buddy that turned me on to these.  Great quality at a great price IMHO.