rear brake disc wear

[Edvalk]

Just checked my rear brake pads and they are in need of replacing. Bought it with 23,000 and my mechanic  replaced them at 38,000 the first time . Im now at 53,000 . i just looked at the disc and I'm a little worried about it . There are no groves or anything like that , nothing that will catch my fingernail when i drag it across . Its not perfectly flat like the front. Should i have it slightly ground at a brake shop . How thin can i go before I should replace it .. I don't want to put the new pads on before I'm sure the disc is good.

[Firefighter]

Manual says rear brake disc thickness: Standard 7.5 mm (0.30 in)  Service Limit: 6.0mm (0.24 in)
                                        and Brake disc runout Service Limit : 0.30mm  (0.012in)

Front disc thickness: Standard 5.0mm (0.20in)  Service Limit 4.0mm  (0.16in)
                                        and Brake disc runout: 0.30mm  (0.012in)

Don't know if a brake shop can turn these or not?   Looks like new ones will cost over 300.00!! Ouch!
Think I would look at used myself.

[hubcapsc]

I didn't measure my rear disk with a micrometer... I judged it to be "worn out" when
there was a significant lip at the edge. I got a cheap one ($20?) from a low-mileage
wrecked bike from eBay, it had, and still has, no lip. Careful if you get a used
one, there are two kinds...

-Mike

[Edvalk]

There is a slight lip . I may look for a used one. Thanks for the replies .

[Hook#3287]

Get a  micrometer or find someone that has one.

My tourers rotors, with over 115 k , are still in service specs.  Close, but still good, even with a slight lip.

The brakes work properly and the pads are worn evenly?  Then you're good, if specs are.

Unless you're the type that it will bother you, which is understandable.

[Chrisj CMA]

The other question is...Why are your back brakes wearing out twice as fast as they should?  Do you rely heavily on the rear brake for stopping? Or maybe do you leave your foot on the pedal a lot?

[Jess from VA]

All mine have lips, but all mine work great (with good OE pads).

[hubcapsc]

All mine have lips, but all mine work great (with good OE pads).

I can't tell that my "new" one is any better than my lipped one... but the caliper
sure does come off easy now 

-Mike

[Jess from VA]

All mine have lips, but all mine work great (with good OE pads).

I can't tell that my "new" one is any better than my lipped one... but the caliper
sure does come off easy now  

-Mike

Yep, mine take a little wiggling.  Some more than others.  My pads last a long time; my riding style does not include hammering the brakes all the time.

[Edvalk]

The other question is...Why are your back brakes wearing out twice as fast as they should?  Do you rely heavily on the rear brake for stopping? Or maybe do you leave your foot on the pedal a lot?

I have been using the back brake more than the front.My back brake works great it's all I need in most situations to slow down or stop and I think I just developed a bad habit of only using it.  I going to start using both front and rear like I should. Funny on my other bike I ride it like I should 80% front 20% rear. Again thanks for all the replies..

[The emperor has no clothes]

The other question is...Why are your back brakes wearing out twice as fast as they should?  Do you rely heavily on the rear brake for stopping? Or maybe do you leave your foot on the pedal a lot?

I have been using the back brake more than the front.My back brake works great it's all I need in most situations to slow down or stop and I think I just developed a bad habit of only using it.  I going to start using both front and rear like I should. Funny on my other bike I ride it like I should 80% front 20% rear. Again thanks for all the replies..

It's good that you acknowledge that. In a panic situation we don't think about what to do, just do it. There have been a few times the powerful front brakes have saved my bacon. Make yourself get in the habit of fronts first then rear.

[Gryphon Rider]

Make yourself get in the habit of fronts first then rear.

Best practice is to get in the habit of using both brakes simultaneously, with perhaps the rear brake slightly before the front.  Engaging the rear brake first starts the weight transfer to the front tire, giving the front tire more traction in the subsequent microseconds when the front brake is applied.  This is not crucial for everyday riding, but it should be trained until automatic so it happens in an emergency.  In many situations of my non-emergency riding, engine braking does much of my slowing for me, but even then if I require more braking I will apply both brakes.

[The emperor has no clothes]

Make yourself get in the habit of fronts first then rear.

Best practice is to get in the habit of using both brakes simultaneously, with perhaps the rear brake slightly before the front.  Engaging the rear brake first starts the weight transfer to the front tire, giving the front tire more traction in the subsequent microseconds when the front brake is applied.  This is not crucial for everyday riding, but it should be trained until automatic so it happens in an emergency.  In many situations of my non-emergency riding, engine braking does much of my slowing for me, but even then if I require more braking I will apply both brakes.

I didn't know that. I thought applying the fronts first transferred weight to the front.

[Tfrank59]

Ed, I wouldn't buy a used rear rotor and ( speaking as a machinist) I wouldn't try to have my worn one resurfaced. If I were you I would buy an aftermarket  rotor like an EBC for about 120 bucks and put new pads on and go from there. if you want to spend the extra money and buy an OEM rotor then more power to you. I bought the EBC rotor recently (my bike had 55K when I replaced the original rear rotor), and it's working fine.  I haven't decided which pads work best with that rotor – right now I'm running  Honda pads but I might try EBC pads, We'll see.  Whatever rear rotor you decide to buy, make sure it's the right one for your year Valkyrie because the thickness changed on the inner diameter --I think it was  1999 or 2000 and later.

[Jess from VA]

Frank, I don't know if it's true, but I've always heard you should run OE pads with OE rotors, and EBC pads with EBC rotors  (Honda pads would probably be fine, but I think EBC are much cheaper than OE, and work good on their own rotors).

What changed with the rotors was the button head vs countersunk mount bolts and rotor holes, not rotor thickness.

I have also read you can run Goldwing rotors just fine (cheaper than Valk rotors).  They are thinner than Valk rotors, but supposedly rated for the same life/miles as the thicker Valk rotors.  (like 3 vs 5 MMs)

[Jruby38]

Ditch the junk OEM pads, they ate up my rotors. Go with Kevlar pads. They stop better, no rotors wear, and polish my new rotors. Only downside is more brake dust, but it wipes right off.

[Gryphon Rider]

Make yourself get in the habit of fronts first then rear.

Best practice is to get in the habit of using both brakes simultaneously, with perhaps the rear brake slightly before the front.  Engaging the rear brake first starts the weight transfer to the front tire, giving the front tire more traction in the subsequent microseconds when the front brake is applied.  This is not crucial for everyday riding, but it should be trained until automatic so it happens in an emergency.  In many situations of my non-emergency riding, engine braking does much of my slowing for me, but even then if I require more braking I will apply both brakes.

I didn't know that. I thought applying the fronts first transferred weight to the front.

Applying the front brakes will transfer weight to the front, but if you are in the habit of delaying your rear brake until after the front brake is applied, you are also delaying the weight transfer, which means you can't get as hard, as fast, on your front brakes as you would if your rear brake were already applied.  Also, it's not as much of an issue to be a little over-excited on the rear brake in the first milliseconds, as the full running weight on the rear tire hasn't yet transferred to the front.

As an aside, I strongly suggest to all riders to practise their riding skills at the beginning of each riding season, including practising controlled hard braking.  Never do this alone.

[Chrisj CMA]

The other question is...Why are your back brakes wearing out twice as fast as they should?  Do you rely heavily on the rear brake for stopping? Or maybe do you leave your foot on the pedal a lot?

I have been using the back brake more than the front.My back brake works great it's all I need in most situations to slow down or stop and I think I just developed a bad habit of only using it.  I going to start using both front and rear like I should. Funny on my other bike I ride it like I should 80% front 20% rear. Again thanks for all the replies..

This is way more than just the cost of replacing brake parts, this is literally life and death. A good friend got seriously hurt in a braking/ avoiding situation. He was a back braker. I believe to this day he could have stopped instead of veering off the road had his reflexes been front brake instead of back. Me and my wife were taken out by a back braker; serious injuries!

Go directly to a big empty parking lot and retrain your brain. It could save your life my friend!

[Edvalk]

I rode around today after putting my oe pads on and all is good.  I am retraining myself to ride like I do on my Ducati. This is the heaviest bike I've ever owned that could have something to do with my braking hiccup .. Also I've never had a  more responsive rear brake on any of the bikes I've owned  So I am defiinately using the front brake and I have you guys to thank for it. Lots of good suggestions of compatible rotors I don't think I need one at this moment but down the road who knows. I just have a slight lip on mine and that seems to be a common thing . 

[Tfrank59]

Frank, I don't know if it's true, but I've always heard you should run OE pads with OE rotors, and EBC pads with EBC rotors  (Honda pads would probably be fine, but I think EBC are much cheaper than OE, and work good on their own rotors).

What changed with the rotors was the button head vs countersunk mount bolts and rotor holes, not rotor thickness.

I have also read you can run Goldwing rotors just fine (cheaper than Valk rotors).  They are thinner than Valk rotors, but supposedly rated for the same life/miles as the thicker Valk rotors.  (like 3 vs 5 MMs)

Jess, I beg to differ--the rotor thickness did change (different bolt heads also resulted)--I know that as I have a rotor from a 2001 Valk and personally measured (and posted somewhere on this forum all the specs) the differences from the '01 and my '98 rear rotor (BTW, I believe front rotors didn't change).  The later rear rotors won't fit a 1997-1998, so Ed better make sure he's buying the correct year rotor.  As for pads,  you're right, I should be running EBC pads on their rotor (according to EBC), but I thought I'd try OE first and see if they'd be better for wear and stopping.  Still can't decide but will probably switch to EBC since like you say they're less expensive.  

[Blackduck]

Never actually measured the difference between the 2 rotors. Cannot be much.
I have 2 rims I swap, 1 of each and have no problems fitting the caliper. Just pull it off and refit without having to compress the pads back.

[Chrisj CMA]

Ok, so we have facts and non facts mixed in from front and rear rotors. Ok, I know guys have put front rotors from Gold Wings on their Valkyrie, never heard of a rear GW rotor being used.

When Valkyrie rear rotors went from cap to countersunk mounting bolts it was the center portion that got thicker, not the brake surface. It is for that thickness change these two rotors are not interchangeable on the same wheel. Mounted on a matching year wheel the assembly is interchangeable on any Valkyrie.

Hope this clears some of this up.

[Jess from VA]

Thanks Jeff. 

[Tfrank59]

Yeah I was saying the inner diameter thickness not the braking area was changed. I was trying to find the post it's from something like July 2015 but the difference is significant it's about a millimeter and a half that rotors would be misaligned and therefore are not interchangeable

[Blackduck]

Tfrank is right, been awhile since I swapped rims but do run a spacer washer to position the caliper properly in relation to the disc.

[Tfrank59]

Here's my post from 2015 that details the differences between 1997-8 rear rotors and later years:

http://www.valkyrieforum.com/bbs/index.php/topic,80852.msg793849.html#msg793849

That's why it's essential when ordering a rear rotor for a Valk that you specify your year model.

(BTW, if you buy an EBC rotor, at least the website I used showed that 1998's have a different rear rotor than the later year Valks.  If a website doesn't show this distinction in its fitment specs, they likely won't ship the right part)

[..]

http://www.webbikeworld.com/Motorcycle-Safety/braking-tips.htm

[..]

I've used this brand pad for 10's of thousands of miles zip, zap, zooming around the country roads of the hilly parts of N GA.

http://www.sixity.com/atv-parts/brake-pads-rotors.html

Both on a Valkyrie and an ST1300.

http://www.ebay.com/sch/i.html?_from=R40&_trksid=p2380057.m570.l1313.TR1.TRC0.A0.H0.XHONDA+VALKYRIE+BRAKE+PADS.TRS0&_nkw=HONDA+VALKYRIE+BRAKE+PADS&_sacat=0