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Blake
Posted on Monday, January 17, 2011 - 02:46 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

The difference in the operating environments of a motorcycle front brake compared to an automobile front brake are significant.

"just physics" : ?

You mean like splitting the atom is "just physics" or like landing a man on the moon is "just physics", or more like cracking your head open by banging it against a brick wall is "just physics"? :/


quote:

Some of the best practice and principles in auto brakes don't translate well to 2 wheeled vehicles.


That would be "just truth."

You say the heat is transferred from the rotor by air. No radiant heat transfer?


Jdugger,
Your objection against our Anonymous posters is odd. Are you wanting to participate in a factual discussion about the technical aspects of brakes, or more interested in personal commentary.

Suggest we stick to the issue and avoid the personal nonsense. Who anony may be is irrelevant. Anony posters have a need to remain anonymous. If you don't like that, you may avoid this forum. That's your only choice.

"I do know, however, because it was posted here, that Eslick's bike had custom, one-off rotors with more beryllium in the alloy. I know that because Michael posted it here."

The way I see it, you mis-spoke and were corrected. The honorable thing to do is to simply thank the folks responsible for correcting your mistaken comments. No big deal. Man up.

It does seem odd that you are so intent upon running down the ZTL brake. Might want to find another forum to do that in. It just doesn't make sense here, especially since they've recently been employed in winning two separate racing championships.

Right, not the bone stock brake system, we get it. We also get that no bone stock anything brake system is being used to win major motorcycle road racing championships.

Buell has done an absolute fantastic job engineering an entirely new type of motorcycle front brake system and has it working well enough to win major racing championships.

Now, you can go on banging your head against the wall about the challenges of racing the stock system or its heat issues, or you can join in thoughtful discussion.

For instance, why do you figure they don't reverse the caliper (move it in front of fork leg) and mount it so that the cooling airstream enters between pads and rotor to help keep the caliper cooler? See my sketches on previous page.
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Blake
Posted on Monday, January 17, 2011 - 03:01 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

>>> Whoever said Beryllium is only for lubricating is flat out uninformed.

No one here said that.

>>> I don't know what the race rotors were or weren't made out of,

Not beryllium alloy as your friend claimed.

>>> but whoever is claiming it's poor engineering or only a lubricant is full of it.

A brake rotor comprised of beryllium alloy, which was the specific issue being address, would constitute VERY poor engineering.

>>> Beryllium was in F1 pistons

We were talking about a brake rotor.

>>> I assure it wasn't a motor oil substitute.

Oh kay... : ? Sarcasm right? I get it. You seem to be unfamiliar with the concept of a lubricating metal and why it would be a poor choice in a brake rotor. No need to feel inferior and lash out with sarcasm.

>>> The stuff is just horrifically bad for you, from being a carcinogen to a number of other things.

Which would make it really doubly poor engineering to use in a brake rotor contrary to what Jdugger asserted.

Cool how these discussions work themselves out.
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Blake
Posted on Monday, January 17, 2011 - 03:18 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

This is too funny...

>>> I'm not a mech-E, but a simple Google search for Beryllium Brake Disc returns more hits than Pete Rose.

The third hit on the list is this very thread. LOL!

The first two talk about beryllium cores.
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Lawineer
Posted on Monday, January 17, 2011 - 03:49 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

>>> For instance, why do you figure they don't reverse the caliper (move it in front of fork leg) and mount it so that the cooling airstream enters between pads and rotor to help keep the caliper cooler? See my sketches on previous page.

For starters, I'm guessing because it's going to blow brake dust all over the fork and it would move mass outward.

I'm sure there is another reason, as cars mount them in the same position.

(Message edited by Lawineer on January 17, 2011)
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Lawineer
Posted on Monday, January 17, 2011 - 04:04 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

The difference in the operating environments of a motorcycle front brake compared to an automobile front brake are significant.

Turns out, the formula for heat transfer doesn't change on motorcycle.

---------------------------------
"just physics" : ?

You mean like splitting the atom is "just physics" or like landing a man on the moon is "just physics", or more like cracking your head open by banging it against a brick wall is "just physics"? :/
-----------------------------------------

Yup, that's all physics. Coincidentally, it's the same in a car an motorcycle.


--------------------------
quote:

Some of the best practice and principles in auto brakes don't translate well to 2 wheeled vehicles.

That would be "just truth."

You say the heat is transferred from the rotor by air. No radiant heat transfer?
----------------------------------------

Not really. Sure, there is, but it's about as close to negligible as you can get, especially if you want to take about radiant heat transfer not going to the air. I mean, holy shit- really? You're going to debate the amount of energy lost due to electromagnetic radiation from the rotor? You're looking a lot of zeros after that decimal point.

It's also very irrelevant. It's all leaving from the surface of the rotor, and a single rotor design still has about half the surface area.

If you want to get technical to avoid the issue at hand, I originally said "Heat leaves through the air, on the surface of the rotor."


But seriously- you have significantly less mass and much less surface area. This shouldn't be a mystery. It's gonna get hot.

Also just speculation, but the traditional dual rotor design probably gets more air due to the aerodynamics, but it's almost impossible to know that for sure without a lot of expensive testing (even a wind tunnel wouldn't help).

(Message edited by Lawineer on January 17, 2011)
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Jdugger
Posted on Monday, January 17, 2011 - 07:28 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

> The way I see it, you mis-spoke and were corrected.
> The honorable thing to do is to simply thank the folks responsible for correcting your mistaken comments. No big deal. Man up.

I *DID* man up, back on THURSDAY the 13th! I found the thread where the information came from and cited Steve Anderson, instead of Michael, and corrected my statement.

Blake, you were the fanboi that couldn't accept that the Buell brake is a design compromise that exchanged some advantages for other disadvantages.

One of those disadvantages is heat. That still remains a fact.

I'm not interested in your fork dicussion because that's not the point. A poster here thought heat wouldn't be a problem with ZTL2, which is a long way from the truth and I noted that, but you couldn't accept that and challenged me on it. Here we are.

And, I'm hardly bashing the brake. You seem to forget I've owned 3 1125r bikes, race two of them, and recently had a full DSB-Spec build done on one of them. That's hardly behavior of someone intent on bashing the platform.

As for anon posts, if they are worth posting, they are worth identifying themselves. Otherwise, I take it for what it is; an anonymous post.
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Court
Posted on Monday, January 17, 2011 - 08:45 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

>>>It's just physics, 1 wheeled or 18 wheeled.

That's why I love the internet . . . . I learn something every day.

How is an 18 wheeler effected when leaned over at 40o from the vertical?

Up until now I'd believed all the crap I read in engineering books . .



Of course it goes on to say . . . when you start making changes to the mass of the front end, say like cutting the weight by 45% that the impact significantly changes the character.

I'm not an engineer . . . I'm a construction worker so I'm essentially unarmed in this debate. My only experience is having done thousands of miles of test riding, working with a motorcycle manufacturer and being in engineering meetings . . . it's all "seat of the pants" and "hearsay" to me.

So, as an engineer, would you think it's better to add the additional 7# (I don't recall the exact number, I think it's quite a bit more than that) to the front of the Buell in order to achieve the additional cooling area?

Also . . . doesn't the Buell rotor have a significantly greater area than most bikes with dual rotors? I'd have to do some ciphering but . . . .

Interesting to learn that motorcycle are no different than an 18 wheeler. Having driven both, I'd have never guessed that.
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Gemini
Posted on Monday, January 17, 2011 - 08:52 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

http://www.carbibles.com/brake_bible.html
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Jdugger
Posted on Monday, January 17, 2011 - 08:52 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Blake,

I want to show you something that better illustrates the point.

This is Ty Howard's KTM. It's the fastest bike (well, rider) in the CMRA. It owns every local track record you can think of, the guy is an absolute stud. If he's not as fast as Geoff, he's barely off the pace... the guy has like 15 track records!

Take a close look at those rotors.



Now, compare those to Geoff May's:



And, just for grins, here's one of mine that's been recently replaced and only has about 3 track days on it:



Now, what's consistent about the ZTL2 systems? Notice the color in the rotors? Now, I don't know what alloy these are made from specifically, but in Stainless Steel a light straw color (like mine and Geoffs are around the edge) will form about 650 degrees F, and that neat looking purple and dark blue on the fins comes in at about 932 degrees!

So, little 'ol me is getting that rotor over 900 degrees F at times! And, I'm just an ordinary club racer!

But, look at Ty's bike. There's no color in the rotors at all. They are clearly used, just never got that hot. Ty is about 13 seconds faster per lap than me at ECR -- or more than a full second per turn! He can outride me in every way, including braking. Why are his rotors not colored at all?
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Jdugger
Posted on Monday, January 17, 2011 - 09:03 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

> http://www.carbibles.com/brake_bible.html

Very nice... thanks for that!
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Court
Posted on Monday, January 17, 2011 - 09:13 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

>>>I don't know what alloy these are made

It varies . . . I've got some test rotors here from Buell R&D and various alloys are experimented with . . . a couple years of development and verification testing went into the ZTL brakes.

One thing I am certain of is that nearly ALL motorcycles made today . . with the possible exception of the lowly TW200 . . . have incredible braking systems.

Another one . . . I recall as you mention this Ty . . is Shawn Higbee. Kinda cool that they took a Ferrari and some souped up Ducati race bike and had a shoot out at Willow Springs.

Ferrari 1:22.3
Ducati 1:19.3
Buell 1125R 1:14.072 (Shawn Higbee)


Look . . . I don't think anybody is questioning anything you say. But statements that infer that the ZTL system is inherently flawed or, perhaps the more laughable inference that the physics of designing a 2-wheel vehicle is no different than an 18 wheel vehicle tend to erode one's credibility rapidly.

If you don't care for the Buell brakes . . . well, you won't be the first to remove them and replace then with whatever you want.
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Jdugger
Posted on Monday, January 17, 2011 - 09:18 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

> But statements that infer that the ZTL system is inherently flawed

I never said that. I said they have heat problems, and that was a design trade off for other advantages, including simplicity and unsprung weight.

On the contrary, I've gone to some trouble to retain the ZTL2 system on my bike and have it work effectively.

Post up a picture of Sean's rotors after he ripped off that 1:14.
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Court
Posted on Monday, January 17, 2011 - 09:32 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

>>>I never said that. I said they have heat problems, and that was a design trade off for other advantages, including simplicity and unsprung weight.

I agree 100%.

I'll bet Shawn's rotors, like those on the Ducati . . . were smoked. Be interesting to see how the Ferrari rotors held. I'm not up on the Ferrari's but I am on Porsche and I'd have loved to have seen how a set of the PCCB would have held up. I just can't get myself to check off the PCCB option for $8,000.

Interesting science.

I've got a couple experimental rotors sitting here that were submitted for Buell testing . . . one from Hayes and one from Ferrodo. Another element that enters in, and the Porsche brakes breech this, is suitability for street use.

Fact of the matter is that one of the considerations . . when you are selling 10,000 motorcycles a year is . . . . well. . SELLING 10,000 motorcycles a year.

The motorcycle market has a funny point at the $10,000 mark and anything you do that takes a bike over that imaginary boundary line for most consumers . . . REALLY needs to be sold to be included.

Bottom line . . (pardon the pun) is that costs matter

Interesting discussion.

By the way . . . you now have me curious to see how the Buells do today and what brakes they show up with.
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Stimbrell
Posted on Monday, January 17, 2011 - 10:16 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Can I just creep in here, keeping low and quiet,and politely ask "why don't they reverse the calliper (move it in front of fork leg)" I have had older bikes that did so am interested in the reason.
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Jdugger
Posted on Monday, January 17, 2011 - 10:19 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

For what's it's worth, Ty's brake set-up is BONE STOCK on that KTM except the pads. That picture was taken at Texas World, too, during a CMRA race weekend. That's the fastest track we have in the CMRA presently, though I would argue ECR cooks brakes a little more being a bit more point-n-shoot.

The KTM is a $24k bike. It's got better components right out of the gate, there's no denying that. The Buells are half the cost. But the color of those rotors tells the story of heat in the braking system.

But all of this is still just a twist on the original post deflecting from the original topic and issue. Contrary to his thought the Buell system would have less trouble with heat, it actually has significantly more trouble. That is the nature of the trade offs in the ZTL2 design.
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Blake
Posted on Monday, January 17, 2011 - 10:31 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

>>> Turns out, the formula for heat transfer doesn't change on motorcycle.

Please compare and contrast the relative amount of convective airflow around each style of brake.

>>> Not really (any radiant heat transfer from rotor). Sure, there is (some), but it's about as close to negligible as you can get...

That's surprising. What is the engineering quantity exactly that "is about as close to negligible as you can get"? Would that be more or less than 10%. Is that true even when the rotor is glowing red hot? Kinda tough to figure.

>>> I mean, holy shit- really? You're going to debate the amount of energy lost due to electromagnetic radiation from the rotor?

Yes, specifically in the infrared portion of the electromagnetic spectrum, most commonly known as "heat". I asked a question. Don't be offended. Odd thing for an "engineer" to be offended by a technical question.

>>> You're looking a lot of zeros after that decimal point.

Really. Here somehow I thought red hot metal was a fairly effective radiator.

(Message edited by Blake on January 17, 2011)
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Blake
Posted on Monday, January 17, 2011 - 10:49 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Jdugger,

I cannot see the color of Ty's KTM brake rotor in your picture. According to your photo and information, your ZTL disk is being heated through to around 650oF. You think that's extreme for a brake disk?

You may not know that the material of the pads has a significant effect on the appearance of the friction/contact surface of a brake disk, no matter the temperature. The pads you see leave deposits on the disk surface. Trying to analyze that surface for color tone indications of heat is extremely unreliable, especially for comparing between two different brake pad compositions.

Maybe the ultimate matchup for a ZTL front brake is a carbon rotor, which reportedly works better when hotter. The MotoGP guys ought to look into that.

Posting a link is not the same as admitting you were dead wrong and apologizing to the people you misled or worse falsely contradicted. Man up.

>>> Blake, you were the fanboi

Again with the personal insult. If you cannot debate the issue absent smallness of personal insult, then either cease participation, or we'll do that for you. Are you understanding me on this?

>>> You ... couldn't accept that the Buell brake is a design compromise that exchanged some advantages for other disadvantages (sic).

If you mean that the ZTL system traded some advantages for others, that is well known. Thus, coinciding with the advanced racing success of a MUCH faster machine, we have the rapid development of a much improved ZTL braking system. From standard six piston ZTL-1 to championship winning ZTL-2.5 in three short years.

Your statement of course in not limited in veracity to the Buell ZTL brakes. The same is true for conventional front brakes on racing machines. They too trade some advantages for others. The only contentions of yours that I don't accept are those that are false.

1. The ZTL-II brake system has huge heat problems.

Truth: As evidenced by your own experience and that of multiple championship winners a problem solved is no longer a problem. Time to move on.

2. Danny Eslick's championship winning ZTL brake disk was beryllium alloyed.

Truth: No beryllium in any Buell brake disk, ever. Mounting or caliper components may have employed a beryllium alloy.

3. The most significant weight savings achieved by a ZTL brake system is in the brake rotor.

Truth: By far the most significant savings in unsprung mass facilitated by ZTL brake system is in the wheel.

4. You can tell the peak temperature of a brake disk by the color of the friction surface.

Truth: Not so much.

:/

(Message edited by blake on January 17, 2011)

(Message edited by blake on January 17, 2011)
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Blake
Posted on Monday, January 17, 2011 - 11:07 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

"But statements that infer that the ZTL system is inherently flawed"

>>> I never said that. I said they have heat problems.



Headline!

Race Bike Has Brake Problems, Wins Multiple Championships


When Shawn on his 1125R was beating a gaggle of IL4 superbikes at Willow in the Formula 1 race, I wonder if he was concerned about the performance of his Buell ZTL front brake?

(Message edited by blake on January 17, 2011)
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Blake
Posted on Monday, January 17, 2011 - 11:18 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Stimbrell ,

>>> Can I just creep in here, keeping low and quiet,and politely ask "why don't they reverse the caliper (move it in front of fork leg)" I have had older bikes that did so am interested in the reason.

Great question! Look back in thread here, and then here. : )
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Jdugger
Posted on Monday, January 17, 2011 - 11:31 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

> Posting a link is not the same as admitting you were dead wrong and apologizing to the people you misled or worse falsely contradicted. Man up.

Blake, I'm not dead wrong about the heat problems in the ZTL2 brake. And, I'm not looking at the bearing surface of the rotor for color. I'm looking at the edges where heat concentrates. Ty's rotors are silver, btw.

I was wrong about quoting Michael and not Steve A. There's no doubt about that, and I long ago cited my sources and made the correction. In fact, I had it fixed before you even called me out on it. However, what we STILL have is a former Buell Employee and Platform Director making a specific statement about beryllium in the Buell rotors and some unidentified, anonymous poster contradicting it. That's not MY problem.

This isn't a man up issue, it's a you are wrong issue. Beryllium or not (which was Steve's claim and my parroting), the ZTL2 system is still heat prone. And, despite Court's comments about Eslick's system being nearly stock, we know that it was not, again whether the Beryllium comment is true or not, Eslick was not using stock rotors or mounting hardware. The heat comments made by someone thinking the ZTL2 was less heat prone was the original issue that started this, my response all along regarding the heat disadvantages of the ZTL2 system is still accurate, and you are still not giving it up.

Maybe you should man up?

Bring your stock Buell to ECR next weekend and let me have a few laps on it. I'll fade the brakes for you in about 5-6 laps and bring it in nice and hot on the pit wall so you can pull the lever to the bar and see for yourself.

I don't know what to tell you other than you are just wrong about this. Quit being a fanboi and realize it was a legitimate set of engineering compromises in the design of the ZTL2, one of the negatives being heat.

As for the racing and championships, if you wanna play that stupid game, I'd start asking questions like "well, why don't we see more single rotor designs, in particular in prototype leagues like MotoGP?" "Why didn't the ZTL win last year in DSB?" "Why has ZTL NEVER won an AMA superbike race, much less superbike championship at the US national level."

But, that's a stupid line of reasoning, and also irrelevant.

> When Shawn on his 1125R was beating a gaggle of IL4 superbikes at Willow in the Formula 1 race,
> I wonder if he was concerned about the performance of his Buell ZTL front brake?

While on the bike, I don't know. But while prepping the bike, I'm going to guess some serious thought went into it? Why, you ask?

Because here's Shawn's bike with upgraded 5mm finned rotor that's brand new...

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Jdugger
Posted on Monday, January 17, 2011 - 11:40 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

> your ZTL disk is being heated through to around 650oF.
> You think that's extreme for a brake disk?

That's the edges of my rotor near the mount points where an underlying copper washer helps suck heat out of the brake rotor into the wheel.

On the inside edges, the color indicates temps closer to 900F.

For the rotor, it's not big deal. It's all that heat getting back into the FLUID, which boils (fades) at about 660F that causes all the problems.
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Lawineer
Posted on Monday, January 17, 2011 - 11:49 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

-------------------
>>>It's just physics, 1 wheeled or 18 wheeled.

That's why I love the internet . . . . I learn something every day.

How is an 18 wheeler effected when leaned over at 40o from the vertical?

Up until now I'd believed all the crap I read in engineering books . .
----------------------------------------

In terms of heat transfer? The same. Leaned over, upside down or right side up, heat transfer of a rotor is largely dependent upon surface area.

Look- heat transfer = thermal conductivity properties * surface area * time * temperature difference. It doesn't care about lean angle, whether there are 1 or a million tires, where the braking system was designed and even if you REALLY don't like it.

As it turns out, it's all just physics.



------------------------------------
Of course it goes on to say . . . when you start making changes to the mass of the front end, say like cutting the weight by 45% that the impact significantly changes the character.
------------------------------------
Maybe, but that's hardly relevant to the discussion at hand- does a single rotor design face additional cooling challenges. Let me help you out with this one and give you a hint. The answer is "yes."

Are there other trade offs that may or may not offset the cooling disadvantages incurred by the single rotor design? Yes. Are they worth it? That's another discussion all together.
------------------------------------
I'm not an engineer . . .
------------------------------
Clearly.

------------------------------
I'm a construction worker so I'm essentially unarmed in this debate. My only experience is having done thousands of miles of test riding, working with a motorcycle manufacturer and being in engineering meetings . . . it's all "seat of the pants" and "hearsay" to me.
--------------------------------------
Well, it turns out I'm also an attorney, so I'm going respond to your hearsay objection by saying it falls under the learned treatises (namely every heat transfer book the world has ever seen, and wikipedia for your convenience), and object to all your previous and forward going statements under a relevance objection and a lack of foundation.
------------------------------------------
So, as an engineer, would you think it's better to add the additional 7# (I don't recall the exact number, I think it's quite a bit more than that) to the front of the Buell in order to achieve the additional cooling area?
---------------------------------------
Objection, relevance ; )
You are, once again, going way off topic. How is that relevant. The issue is, does a single rotor design have additional cooling challenges?

Whether trade off of weight for surface area is a good one in terms of overall bike performance is completely off topic.

-----------------------------------------
Also . . . doesn't the Buell rotor have a significantly greater area than most bikes with dual rotors? I'd have to do some ciphering but . . . .
-----------------------------------------
I seriously doubt it.



In terms of surface area of just the braking surface (excluding the stuff that goes down to mount it on a traditional design), it's not even close. I just did some napkin math and a dual rotor design has about 35% more surface area before the rest of the stuff is factored in.

In fact, I'd go so far as to say ONE rotor on a traditional brake design has more effective cooling surface area due to the non-braking surface area, but that's speculation.

-----------------------------
Interesting to learn that motorcycle are no different than an 18 wheeler. Having driven both, I'd have never guessed that.
--------------------------------------
I never said that the vehicle kinematics were identical or learning to drive them was a similar experience. You're just taking my comments out of context and creating straw-man arguments because you have nothing useful to contribute to this discussion.

I said that the physics, heat transfer in context, doesn't change from one vehicle to another and you're comparing vehicle kinematics and learning to drive a semi vs a motorcycle. And it's all STILL JUST PHYSICS. It even still, it turns out the same exact rules of physics applies to 18-wheelers and motorcycle. There isn't some mystery Physics-X that comes along for motorcycles.
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Blake
Posted on Monday, January 17, 2011 - 11:52 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

>>> However, what we STILL have is a former Buell Employee and Platform Director making a specific statement about beryllium in the Buell rotors

You no read good. He was not talking about the rotors.

>>> On the inside edges, the color indicates temps closer to 900F.

Point that out on your photo please. I cannot see it.
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Lawineer
Posted on Monday, January 17, 2011 - 11:55 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

>>>> Really. Here somehow I thought red hot metal was a fairly effective radiator.

When your rotors are glowing red, you give me a call. When it does, I'll tell you your braking system has some serious problems. Until then, radiant heat transfer is negligible compared to conduction/convection.

If anything, it's damn close to constant between a traditional and single rotor design. Unless of course, it's not physics anymore because we're on two wheels.

(Message edited by Lawineer on January 17, 2011)

(Message edited by Lawineer on January 17, 2011)
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Jdugger
Posted on Monday, January 17, 2011 - 12:04 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

> You no read good. He was not talking about the rotors.

Fair enough, but the following quote, by Steve Anderson, is easily enough interpreted that way.... read again:

"All the improvements that had been made to Danny Eslick's front brake system were made to the B2s -- it literally had rotor mounts and rotor that were essentially identical in form to Danny's, though there was a little less beryllium in the production parts."

From here, 3rd post:

http://badweatherbikers.com/buell/messages/290431/ 571747.html?1276217787

So, perhaps he's talking about caliper pistons then? Other than the caliper itself there's nothing else the comment could be talking about. He's talking about *something* in the brake system, clearly. You tell me -- log in as anony real quick, make a post as if it's someone else, and that will settle the discussion once and for all.

> Point that out on your photo please. I cannot see it.

The pink, purple and blue of the inside rotor fins at the bottom of the picture. The camera color isn't great, I admit -- it's a phone camera that took the pic.

If you wanna see it in person, and a few other rotors like it, come on out to ECR this weekend. It's a member weekend and I've got a garage full of shagged rotors. Some of them have bits of skin, glove leather, and tire tire warmer on them, too, where I wasn't careful enough after coming off track and accidentally touched them, melting stuff on to them.
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Blake
Posted on Monday, January 17, 2011 - 12:07 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

>>> Leaned over, upside down or right side up, heat transfer of a rotor is largely dependent upon surface area.

>>> Look- heat transfer = thermal conductivity properties * surface area * time * temperature difference. It doesn't care about lean angle, whether there are 1 or a million tires, where the braking system was designed and even if you REALLY don't like it.

Convective heat transfer, that which you claim is the only form significant to brake disk cooling, also includes a myriad collection of fluid mechanics not the least of which is the magnitudes of cooling air flow itslef.

>>> As it turns out, it's all just physics.

No competent engineer I know would ever make such asinine comments in response to a technical debate.

As much as surface area, the amount of convective cooling airflow is a MAJOR factor in engineering design considerations for a disk brake.

The convective cooling airflow environment inside an automotive wheel is vastly different from that of a motorcycle front brake.

Ignoring that fact indicates an intent to troll and argue rather than engage in thoughtful discussion. We don't tolerate trolling here, especially by arrogant newbs claiming to be engineering experts.

Understood?
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Blake
Posted on Monday, January 17, 2011 - 12:27 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Jdugger,

I don't post as anonymous.

>>> Fair enough, but the following quote, by Steve Anderson, is easily enough interpreted that way.... read again:

In light of anonymous' correction of your false statement, anyone with a brain would figure out that it was either the rotor mounts or caliper components that Steve was referring to. Your reaction was to go all indignant and flame the person providing truthfull information. VERY bad form. You owe an apology.

>>> So, perhaps he's talking about caliper pistons then?

You got it, or rotor mount components.

>>> Other than the caliper itself there's nothing else the comment could be talking about. He's talking about *something* in the brake system, clearly.

Except for the specifically mentioned "rotor mounts".

>>> You tell me -- log in as anony real quick, make a post as if it's someone else, and that will settle the discussion once and for all.

I don't post as Anonymous. We protect the integrity of that feature here very resolutely. If I ever posted as Anonymous, I'd lose all credibility with the other custodians, and rightly so. There is no need for any further clarification; Anony has already provided that, so has Court, and so have I. You are free to accept or doubt the information as you wish.

I'm still scratching my head wondering how anyone could imagine Buell using highly toxic (illegal) material for the friction surface of a motorcycle brake rotor.

I don't see the colors you are talking about in your photo. If you need a magnifying glass to see it, it likely isn't a factor. What color are the surfaces of the holes? They appear golden hued to me. So based on your temperature versus color information, it seems pretty clearn that your rotor isn't getting as hot as you imagined.

That said, racing brake rotors can get red hot as a matter of normal use.

Heat is an issue that must be addressed for every front brake on every motorcycle ever made. The Buell is no different.

As your glib friend likes to say, the physics don't change.

What is amazing is the leap in technology Buell has been able to achieve in just three years, going from standard ZTL to ZTL-2.5 and winning a championships in the process.

Championships are irrelevant? We're talking about brake performance, and winning an AMA championship is irrelevant?

You lost me on that. LOL.

Why hasn't ZTL been implemented elsewhere? There's the issue of the patent, and then the fact that it is brand new technology just now making its way to the Superbike playing field.

Ten years from now, who knows. If reduced unsprung mass via a lighter front wheel is important, it likely will see its way into the mainstream.

It's a damn shame that H-D killed the game just as Buell was poised to go large in Superbike.

(Message edited by blake on January 17, 2011)
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Court
Posted on Monday, January 17, 2011 - 12:27 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I don't think it's trolling at all . . . I work with top engineers and attorneys here in NYC daily . . . there are some who are, in all candor, better than others.

Some of the ridiculous foregoing statements told me all I needed to know.

I'll stay on the sidelines . . . . any attempt to discuss this will most surely go the way of the fabled wrestling a pig in the mud joke.

Enjoy yourselves and I hope your brakes work . . mine are fine.
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Lawineer
Posted on Monday, January 17, 2011 - 12:28 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

1. Where do you think heat from the brake fluid goes?
2. The cooling from brake fluid (to the AIR) is effectively constant between the two designs, except that the dual rotor design might again have a slight advantage for having two sets of lines, more fluid, etc.
3. Do you know what convective cooling is? Because that's pretty much how the brake is cooling itself to the air. Per, wikipedia: "Convective heat transfer, often referred to as convection, is the transfer of heat from one place to another by the movement of fluids."

It's also that formula I posted earlier.

I just thought you should know that before we went any further.

Convection, conduction and radiation. Those are the 3 basic heat transfer methods. Convection and conduction are pretty much the same thing, except conduction is more solid-to-solid heat transfer. Same formula applies (in essence, the coefficients have different names).



>>>>The convective cooling airflow environment inside an automotive wheel is vastly different from that of a motorcycle front brake.

Yes, it is. What's your point? You posted up some completely irrelevant picture of kinematics. In the end, the heat transfer in a car rotor and motorcycle rotor are the same exact physics using the same exact formula. Some of the numbers you plug in will be different, but that's neither here nor there and it certainly has NOTHING to do with the image you posted. If I didn't know better, I'd think you were trolling me.

(Message edited by Lawineer on January 17, 2011)
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Lawineer
Posted on Monday, January 17, 2011 - 01:01 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

>>>Heat is an issue that must be addressed for every front brake on every motorcycle ever made. The Buell is no different.

As your glib friend likes to say, the physics don't change.
-------

The physics doesn't change. That doesn't mean everyone gets the same results with different designs.
If you design a 6" parachute and I use a traditional parachute, the physics is the same. The end result will be very different.

I'd also be very interested to hear exactly what I said about braking doesn't apply in cars.

(Message edited by Lawineer on January 17, 2011)
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