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Buell Forum » Tale Section (Share your tales of adventure here.) » Archive through October 17, 2006 » Laguna Seca 2005: MotoGP, A.S.B.N, The Luv Shack, and More Streamly Suckless Stuff » Cecil Explains Benefits of ZTL Brake ?(two very different accounts of Erik's presentation) » Archive through July 18, 2005 « Previous Next »

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Blake
Posted on Monday, July 18, 2005 - 12:14 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Dinner at Rocky Point Restaurant south of Carmel, CA on Friday, July 8th was a real treat. Thanks to Rex and Woz and all the folks of American Sport Bike Night for their hard work and warm hospitality. I have pics of everyone to post once I get them downsized and compressed.

My pal Cecil who saw the exact same presentation by Erik Buell that I did had the following to say ...


quote:

He started off with the ZTL brake and explaining why it's so great. But he didn't stop there, he went on to say that radial brakes are dumb, the brakes on every other sportbike made are dumb, and that having both great handling AND horsepower in a motorcycle was "going to the dark side." Huh???

I found Mr. Buell to be very contradictory. He said, "sure we could have dialed 1-800-Brembo for our brake. But we didn't go to the dark side. It was expensive and difficult but we decided to design our own ZTL brake." Now if memory serves me correctly, Buell dialed 1-800-Nissin for the brake on my 98 S3. The carrier spacers on that brake eventually failed because of engine vibration causing the disk to rattle all over the place.

He then went on to compare the XB's brake and wheel intertia to that of the RC51. A design which is close to 6 years old and notoriously heavy. Why doesn't he compare the intertial forces of the ZTL to say, any 600 on the market? I wouldn't even want to consider the differences between the ZTL and the brake systems of the new liter bikes.

Never once did Erik state that the ZTL stops you any better. Nor did he state that it has better feel. He just said it's better than the RC51 and tried to convince the room that the ZTL is better BECAUSE it's different. He did make some very valid points regarding quality though. And I suspect that quality control is more to blame for the ZTL design than anything else. As I said before, the traditional hub based carrier and disk vibrated themselves apart on the tube framers. This was eliminated with the ZTL.

And that ladies and gents is a classic case of "the tail wagging the dog." Buell admitted that it would be cheaper and easier to dial 1-800-Brembo. I'd say that using a Brembo radial caliper and master cylinder would stop you better too! But getting it to work with that iron lung of a motor causes some quality issues. So instead of using a better motor, Erik Buell redesigns the brakes!

He then states that the only reason manufacturers use Radial brakes is because "you can center them on the calipers easier." You guys think I bend the truth a bit? Holy crap! Yea, that's why every high performance motorcycle manufactured today runs radial mounted brakes. That's why MotoGP bikes run them too. So they can center them on the caliper easier. RIGHHHHT. It has nothing to do with brake feel or using a smaller, lighter, disk and maintaining stopping power. Erik Buell is quite literally full of crap on this point and he was only reinforcing to all those in the room who purchased his product that they didn't make a complete mistake! He was justifying his engineering decisions with half truths.

If the ZTL brake is so great, why doesn't anyone else use a similar design? Why do all of the Buell racers except 1 convert the brakes to dual discs?

Then he went into Belts and why they're better than chains. Oh man, I was just biting my lip so hard at that point. Sure, belts are great until you start running them on a bike with real horsepower. At which point belt size increases logarithmically to HP output. But he wouldn't know anything about that because Erik Buell is quite content with 90rwhp bikes. Why? Because HP is stupid he says.




Ignorance may truly be bliss when it comes to understanding and appreciating the very substantial and very real benefits of the ZTL braking system over conventional systems on a street bike. Or maybe one needed a bit of a technical/engineering backround to truly grasp and appreciate what Erik was explaining. Or is that the same thing? I just know that it is perfectly valid and crystal clear to me.

I recall Erik explaining that the benefits of the ZTL brake system were two fold. First was that the ZTL configuration's was very simple/elegant allowing it to achieve extremely stable manufacturing tolerances and an assembly free of shims. Basically less parts and a better more direct load path means less parts under stress, a truly elegant design. The significant benefit of the simplicity and stable tolerance stackup is likely lost on non-technical types, but it is real and substantial.

Second, and mostly important, the ZTL system allows a significantly lighter unsprung weight, yes even over any current sportbike, with the very real and substantial benefits in real world street bike riding where not all curves are racetrack smooth/predictable and not all lines through those curves are well known. On the contrary, roads in the real world are often bumpy and curves are frought with various obstacles or imperfections thus often requiring serious steering corrections while leaned over.

A front suspension that allows the rubber to stay in contact with the road will always perform better and provide a larger margin for safety in such situations. It is that simple. All else being equal, the front suspension with significantly less unsprung mass will better stay in contact with an uneven road surface.

I recall Erik explaining that the ZTL configuration eliminated a bunch of tolerance stack-up and thus eliminated any need for shimming the caliper in order to mate-up acceptably with the disk.

I recall him saying that the reason the racing teams switched to the radial mount calipers was that doing so precluded the need to shim the calipers in order to achieve acceptable caliper to disk alignment. It saved them time and hassle in shimming. So yes, radial mount (tension joint) calipers have a real benefit for the racers over the old style shear joint mounting scenario. Other than that, nadda, zip, zero benefit for the street.

Only one Buell racer used the ZTL brake system? That's news to me.

Why don't other manufacturers implement a ZTL brake on their sport bikes? Dang pesky patent might have something to do with it. Even if they could invent a different version of the ZTL configuration, they would likely be shy from copying Buell. Remember the Honda concept bike that had the perimeter brake?

Cecil also went on to claim that drive belt/chain strength must increase exponentially with engine HP. Where he got that I have no idea, but it is complete bullshit.

It takes only so much belt or chain tension to either wheelie a bike or skid the rear tire. The wheelie condition is likely the max tension design loading for the belt. You can rev the engine and drop the clutch on a Blast and loop it quite easily. That is the most tension the belt or chain is ever going to see no matter what HP the engine might be. A heavier bike with a longer wheelbase will put more tension load on the drive chain/belt. HP is largely irrelevant.

What I recall is Erik talking about how Buell working with Goodyear now have a belt that is as strong and resistant to catastrophic damage as a chain. That belt strength and toughness for the XBs has continually improved with each model year.

I was listening intently. I don't recall Erik stating that HP was stupid or any of the other inflamatory remarks Cecil attributes to Erik.

So there you go, two completely different reports on the exact same event.

(Message edited by blake on July 18, 2005)
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Blake
Posted on Monday, July 18, 2005 - 12:26 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

BTW, other manufacturers are using belt drive now, BMW and I believe Yamaha. Guess they are stupid and arrogant too eh Cecil?

Chains are cheap, heavy, dirty, noisy, require maintenance, and they stretch.

Belts sometimes break but are constantly improving. Someday they may well be as resistant to damage as chains and and more durable than chains. Then who will be the arrogant one?
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Jima4media
Posted on Monday, July 18, 2005 - 01:50 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Blake,

Buell's ZTL brakes are perfectly adequate for the street for 99% of the riders out there that are using them.

The thing is, for less money than a Buell XB you can buy any 600cc bike with dual radial brakes, that will out stop the Buell, not to mention out-perform it in every other performance measurement as well. For the same amount of money, you can get a liter bike, that way out performs it.

The only meaningful measure of brakes, is stopping distance, freedom from fade, and not locking up when hot, wouldn't you agree?

As far as drive mechanisms go, I prefer shaft drive, belt drive, and chain drive, in that order. From a maintenance, and performance standpoint. When used in a racing application, chains make more sense, because you can vary the ratios of the sprockets, which you can't do with a belt. Almost all the race teams use a chain drive. There has never been anyone who has won with a belt that I know of.

Will belts do as well as chains in the future? Time will tell.

IMHO,

Jim
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Blake
Posted on Monday, July 18, 2005 - 03:07 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Ah for less money you can buy a chinese or korean motorcycle too. Have at it.

Seriously though, why is it do you suppose that people spend so much more money for a Ducati or a BMW or a Moto Guzzi, or a Buell? Sorry Jim that bullshit logic is just that, bullshit. It has no place in a technical discussion about the merits of the ZTL brake.

The only meaningful measure for a braking system to you may be stopping distance, fade, and not locking up. I can assure you that as both an avid street rider and road racer I strongly disagree.

You ignore feel and bite, and most disappointingly you completely dismiss the main advantage of the ZTL brake system, it's effect on front wheel unsprung mass.

Try again. I will quarantee you that the stock Buell ZTL brake will stop ANY sport bike to the point of doing an endo; at one point the Buell with a ZTL held the world record in stoppie distance traveled. Not sure if it still does or not.

If the ZTL can stop Mike Cicotto on his FX Buell racing machine, then I defy you to find ANY street rider for which the brake is inadequate. That is simply bullshit and you know it.

If you don't recognize the benefits of losing more than 6 LBs from the unsprung weight of the front wheel assembly, well amigo, enjoy the Kool Aid.

I guess you heard the same presentation as Cecil.

The reduction in unsprung mass is HUGE. It's too bad some don't appreciate how truly revolutionary the ZTL system is and that if they could have, Honda would have done it first.

You actually think a Buell cannot stop or turn with a Jap 600 IL4? Sorry bud, you be wrong. I've ridden both. The Buell stops just as well and turns better, way better.
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Brianh
Posted on Monday, July 18, 2005 - 09:00 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Blake Blake Blake,
You didn't hear Erik preach to you about "why do you need lots of HP?" You completely missed that?

I agree with everything you (and Erik) said about the ZTL. But again, you or he never said it actually works better than the brake systems found on modern motorcycles. I totally understand the elegance of a simple design. What I question is the reason for the design. Why did Buell spend so much time and money on the ZTL? It wasn't for greater brake performance was it? No, it was to get their quality situation under control. My position is that there wasn't anything wrong with the Nissin setup on the tube framers! It's the motor and its inherent vibration that causes quality problems. Instead of fixing the 1 major issue with the bike, Buell fixes the hundreds of resulting symptoms.

Do you really buy all that drivel about the benefits of radial calipers? Radial calipers are only beneficial to the mechanic? C'mon dude, wake up. You claim to be an engineer and you don't see a benefit to bolting the calipers from behind instead of from the side?

As for wheel weights and inertial forces go, I challenge Mr. Buell to compare the XB wheel to that of a CBR1000RR. He'll find that he could have reduced inertial forces by simply dialing 1-800-Brembo and using a modern wheel.

As for racers, outside of that 8 piston caliper job from Hals (I think?), every other XB race bike I've seen runs traditional dual discs up front. In fact, Mr. Buell has a problem with our buddy Kneedrag because his race bike not only scratched the brakes, he replaced the entire front end with one from a GSXR1000. Know why? IT WORKS BETTER!

Lastly, belt strength eh? Take the stock belt of an XB and use it on a bike with 160 rwhp. How long will the teeth on a belt last if you punch it from a dead stop with 160rwhp on tap? Think you'll have any slippage? Rip off a few teeth?
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Jima4media
Posted on Monday, July 18, 2005 - 11:49 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Brian,

I was going to bring my portable DAT recorder to record Erik's presentation, but I left it on my desk. It would have been useful to recall Erik's exact words, instead of someones selective memory of the event.

I remember Erik ragging on RC51's, radial brakes, 1-800-Brembo, and the answer as to whether Buells will be at the Daytona 200 next year.

You have to enter a race to win a race. And once you are entered, you have to have superior equipment and superior skill to beat the other entrants. The stopwatch doesn't lie.
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Jscott
Posted on Monday, July 18, 2005 - 12:32 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

What was Erik's response about the 200?

Our favorite insider said the following after many expressed disapointment after this years 200.

"Buell will run and have a very visible presence in the 2006 Daytona 200."

http://www.badweatherbikers.com/buell/messages/4062/102458.html?1110497326

(Message edited by JScott on July 18, 2005)
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Jima4media
Posted on Monday, July 18, 2005 - 12:39 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Buells won't be in the 2006 Daytona 200.
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Jima4media
Posted on Monday, July 18, 2005 - 01:04 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Blake,

Dig out your January '05 issue of Motorcycle Consumer News. Page 23 lists the Ten Best 60-0 stopping distances.

The best may surprise you.

Dig out your January '05 issue of Motorcycle Consumer News. Page 23 lists the Ten Best 60-0 stopping distances.

The best may surprise you.

1. 1999 Triumph Speed Triple - 106.7'
2. 1997 Suzuki Marauder 800
3. 1997 Yamaha YZF600R
4. 1998 Ducati 750 Monster
5. 1998 Suzuki TL1000S
6. 2002 Honda VTX 1800
7. 2002 Harley V-Rod - 109.5' They dialed 1-800-Brembo
8. 1998 Buell M2 - 109.6' - single rotor 6 pot caliper
9. 2003 Trimuph Speed 4
10. 2002 Ducati Monster S4 - 109.8'

Not listed in top 10 - 2003 Buell XB12S - 123.3' - Perimeter brake - 6 pot caliper

(Message edited by jima4media on July 18, 2005)
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Jscott
Posted on Monday, July 18, 2005 - 01:05 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

[Scott puts on his hat of optimism on]

Perhaps they will not race the Formula Extreme 200 because they will be racing in SuperBike?
They are supposed to release 2 new bikes this year, only 1 of which is getting much discussion.
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Choptop
Posted on Monday, July 18, 2005 - 01:28 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

ZTL = engineering for engineerings sake... NOT for perfromance output.

other brake systems = optimum performance regardless of how may parts, how many levels of tolerance variance.... if it works better in real life, on the track... use it, cuz it helps win races.



Lots of things look great on paper, seem like they should be "better" in principle... but fall short in real life.



I'd rather great stopping distance in my brakes....

rather than riding around knowing that my brakes look better on paper than other systems and giving up all the advantages of the others.


erik also chose the RC51 front wheel system... anyone know why? Could it be one fo the heaviest out there? hmmmmm
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Jima4media
Posted on Monday, July 18, 2005 - 01:34 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Scott,

I can guarantee you that Buell won't be in Superbike next year, or the year after for that matter.

Beyond that, who knows?
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Blake
Posted on Monday, July 18, 2005 - 02:01 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Cecil (Brianh),

I'm addressing the misinformation that you posted. Erik's point about HP is of course subjective, but of course it is true that beyond a certain point, more HP becomes not only unusable but dangerous. Where that point lies is different for different people. Certainly you would agree that a street bike with 1,000 HP would be silly. The current state of top contending MotoGP machines has pretty much shown that more than 250 HP is simply not usable, even on a road racing machine. More power simply spins the rear wheel more. At Laguna Seca the Suzukis and Kawasakis demonstrated that power was not as important as handling.

Buell only makes the exact same point but for street bikes. Makes perfect sense to me, though I agree, a bit more power would be nice. However, until you've ridden a 120+ RWHP Buell, you simply have no idea how violently powerful such a bike really feels.

You want to punch it on a bike with 160 HP? That may work okay on an IL4, but try that on my meagerly powered 100 HP Buell Cyclone and the front wheel will likely smack you in the forehead before you can let off the throttle. Unless you ride on slicks and wheelie bars, the belt tension simply will not exceed that which causes a wheelie, no matter how much power you pump into it. I know a guy who looped his ~65 RWHP S2 by just dropping the clutch at four grand. Of course the spinning flywheel momentarily allowed a much higher amount of power to dump into the drive belt. Point being, it doesn't take much power in 1st gear to tension up the belt enough to cause the bike to loop over backwards. Not with a clutch that is made to transfer serious amounts of torque.

But I mainly take issue with your incomplete and distorted view about the benefits of the ZTL brake system. You seem to be completely ignorant of its very real and very significant benefits, not necessarily as a superior decelerator, but as a means to significantly reduce the unsprung mass of the front wheel assembly and thus greatly improve the ability of the front wheel to hold the road over a real world irregular/bumpy surface.

Maybe it is too difficult for some to understand the huge benefits of reducing unsprung mass. Maybe it will help to imagine the two impossible extremes, zero unsprung mass and infinite unsprung mass. Though impossible and unrealistic, looking at the behavior of those two imaginary extremes might help one better grasp the issue and the benefits of less unsprung mass.

A suspension having infinite unsprung mass would be impossible to damp, once in motion it would stay in motion leaving tire forever moving away from the surface of the road. Not a good thing.

A suspension with zero unsprung mass would require no damping and it would always maintain the front tire in perfectly consistent contact with the road.

Less unsprung weight, a LOT less unsprung weight, not better braking is the major benefit provided by Buell's ZTL single disk brake system. In fact, I believe that Erik even said that the braking power of the single disk ZTL was not necessarily superior to the conventional dual disk/caliper 8 pot systems. He said it was adequate, even for racing.

Hals only ran the special 8-pot calipers at a few of the high speed tracks last year. They ran the stock calipers most of the time.

As a structural analyst I was honestly never convinced of the advantage being touted about the radially mounted brake calipers. Structurally I could not see it. Now I know why. It isn't there to any significant extent. I like radially mounted brake calipers better though. No shims. That is a good thing for sure. Kudos to whoever came up with the idea of radially/tension mounted brake calipers. As with the ZTL, the braking system design was optimized for something other than improved braking performance.

I thought I already explained the issue of belt design strength requirements. Beyond a certain point, HP is simply not part of the equation dominating required belt strength.

To be honest, there is one other factor in belt or chain design/sizeing that HP does effect, the ability of the belt to absorb and dissipate heat. So a belt does need to be large enough to keep from overheating. You have a point there. But it in no way means that belt strength must increase exponentially with engine HP. The converse is actually true. Motorcycle HP can increase exponentially wrt belt strength.

I guess you've never paid much attention to the FUSA Thunderbike Buell racing machines. Lots of them use the stock brake setup. Didn't the 2004 FUSA National Team Challenge Championship winning Buell used the stock front brake.

Granted the existing state-of-the-art in racing brake technology is in conventional hub mounted dual carbon disk setups. Not sure that means that the ZTL is inferior for racing. Given time and lots and lots of money, it would be interesting to see how well an 8-pot carbon disk ZTL could be made to perform.

But I digress, again, the major advantage, and it is substantial, is in reduced unsprung mass through significantly reduced wheel hub and wheel spoke mass and one six-pot caliper versus two four-pot calipers.

Like Erik said, the engineers at Honda et al strive to carve ounces from their front wheel assemblies. In one fell swoop with the ZTL brake system, Buell chopped off over 7 LBs!

Yes, I agree that the latest wheel assemblies of the repliracers are probably lighter than that from the old RC51. How much lighter? Maybe a pound or two at best. Japan Inc. has indeed reduced the diameter of their front brake disks. Why? For better more powerful braking? Nope, smaller disks reduce braking power. Why then? Answer... To reduce unsprung mass of the front wheel assembly. They spent a LOT of money to get their front brakes to work with smaller diameter disks so that they could reduce the unsprung mass of the front wheel assembly by ounces. But they are still a long ways from matching the first generation Buell ZTL lightweight front wheel assembly. Care to wager that the Buell front wheel will grow lighter still in future generations?

The effect on real world performance of the Buell ZTL brake system is truly as significant as was the advent of the front disk brake over drum brakes. Unfortunately its benefits may not be so immediately apparent to the laymen sport bike rider. But those very real and very significant benefits are indeed there.

Besides, it also looks cool as hell. : )

Too bad you left the scene so early. You could have spent some time talking guitars and music with Erik. He just submitted patent application for a new electric guitar design.

You really should reread your post on SacBORG. You talk about arrogance? Unbelievable.
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Danny
Posted on Monday, July 18, 2005 - 02:11 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 know, just throwing ideas out here...

Could one of the reasons the stopping distance is longer for the XB is because the wheelbase is short and the cg is closer to the pivot point, so the bike comes up in a stoppie faster? Then the operator has to modulate the brake to control the stoppie, adversely affecting the braking distance.

I'm sure I'm missing something, and it's going to smack me in the head when it's mentioned, but right now I can't think of it.

Danny
95 S2
02 V-Strom
Can I mount a 52-liter topbox on the 06 Discovery?
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Blake
Posted on Monday, July 18, 2005 - 02:16 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Jim,
That is a great illustrative example of the fallacy of braking performance of the repliracers in the real world, where complete panic stops do indeed comprise a major performance measure for a motorcycle.

Do you figure that wheelbase might also affect braking distance? The XB with a 52" wheelbase thus is no class winner in braking distance contests. Frankly I'm surprised that the R6 is in the bunch; it's the only repli-racer to show in the top ten.

Alan (Chop),
Where do you get the idea that the repliracer braking system will stop a street bike any better than a ZTL system? As a racer you should know well that optimal braking/stopping distance is more affected by optimum initial bite and feel than by outright braking power. Yes, braking power must be adequate to approach inducing either a skid or stoppie condition, but beyond that more braking power will not improve/reduce stopping distance.

And like Cecil and others, you conveniently ignore the benefit of significantly reduced unsprung mass. Why? I mean seriously, if you truly don't understand the concept, please ask some questions and I'll try to better explain it so you can understand it.
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Blake
Posted on Monday, July 18, 2005 - 02:30 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

What we need is a shot of two identical bikes with identical suspensions, one with a Buell ZTL brake/wheel assembly, the other with a conventional brake/wheel assembly. Optimize spring rate and damping for each setup. Run them over the exact same path on a bumpy road and record the suspension action with a high speed camera and with an LVDT setup to measure front suspension behavior. Compare the two.

That would illustrate clearly the benefits of reduced unsprung mass.

What you would see is the tire on the conventional wheel/brake assembly spending a lot more time out of contact with the road surface.

You would also see that the tire on the ZTL wheel/brake assembly would be in contact with the road surface much more consistently, a very good thing in a panic situation or in any situation.

Which would you say is better in a panic stop situation or when leaned over having to negotiate an obstacle on a bumpy road...

1. A front suspension/wheel/brake assembly that holds the road better or,

2. One that has more raw braking power, well in excess of that required?

Engineering and innovation for the real world my friends. It saves lives. Short of that, it will undoubtedly save someone from going down. I'm sure it has already.

(Message edited by blake on July 18, 2005)
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Reepicheep
Posted on Monday, July 18, 2005 - 03:07 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I wonder if the ability to build a lighter front wheel assembly also allows more flex to the wheel.

When cranked over at full lean, the flex of the tire sidewall is most of your "suspension". I wonder if the ZTL front wheel is giving a little additional "travel" in addition to the fact that it requires less damping.

Probably not, but it's an interesting thought.

I could immediately feel the difference between ZTL upside down shock front setup on my 9sx and the traditional non upside down shock with single traditional rotor on my Cyclone.

The first time I was cranked over at high lean making a turn on washboard pavement on the 9sx I was amazed, where the Cyclone would have been nervous and vague, the 9sx felt like the damn front wheel was welded to the road. That was my moment of epiphany... The advantages of a ZTL rotor have little to do with stopping.
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Jon
Posted on Monday, July 18, 2005 - 03:07 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Jim,

In light of your first post here, what's all the fuss about Buell's brakes? It sounds like they work well. We're talking street bikes here, not race bikes, right?

All,

Erik's talk was not presented as a Steven Hawking-esque treatise on the world's best brakes. He's explaining what he thinks and what his decisions have been. This was a casual setting among friends. You might disagree and that's cool. But all this heat seems out of proportion.

I had the pleasure of destroying cigars with Erik after the crowd left Rocky's. It was me, Augie (who brought the smokes) and Erik. Kirsten sat in the car 'cuz it was getting cold. Erik told us that "Buell now has bike to race with". Did he mean a new bike as in '06? '07? I don't know. He also said that he has no interest in putting a race bike in the showroom, but definitely on the track. I assume that if anyone wants to aftermarket their Buell into a race bike, they are free to do that.
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Blake
Posted on Monday, July 18, 2005 - 03:39 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Bill,
I think that if the wheel were to flex enough to amount to any significant suspension action it would cause big problems for the front brake disk distorting and hitting the caliper/pads, pushing the pistons back into the calipers and leaving you with a big fat dead brake lever next time you grabbed for it.
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Reepicheep
Posted on Monday, July 18, 2005 - 03:45 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I think you are right, but in the interest of trying to create an Urban Legend (I always wanted to start one), the location of the caliper *is* exactly where you would put it if wanted the wheel assembly to flex in response to lateral pressure from the contact patch without moving the pads/pistons/calipers ; )
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Choptop
Posted on Monday, July 18, 2005 - 05:26 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Not ignoring any aspect of unsprung mass


please compare the weight of a Buell from wheel assembly to the weight of any current 600-1000 repli-racer....


also take this into consideration....


of allllllllll the braking systems out there....


with allllllll the factors taken into consideration, weight, feel, braking distance.. on and on....


why do allllllll the race teams still go with dual discs from 1-800-Brembo?

are they just stupid and havent considered unsprung weight?

If Erik Buell the ONLY one out there to figure this out? and everyone else is an idiot?

These teams have millions on the line, trust me, its allllllll been taken into consideration.

Even IF the ZTL system might be a touch lighter, and thats IF, they have still alllll gone with another system because it offers more benefit in other areas.

There is a trade off for everything. The trick is finding out which total package works best over the widest range of parameters.


Erik can wave the flag of unsprung weight all he wants. He can wave it all the way to the back of the grid.

If the total package doesnt work as well as others, one outstanding feature doesnt mean a hill of beans.


again... its engineering for engineerings sake, not for performance.
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Jlnance
Posted on Monday, July 18, 2005 - 06:38 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

why do allllllll the race teams still go with dual discs from 1-800-Brembo?
are they just stupid and havent considered unsprung weight?


Unsprung weight only matters when there are bumps in the road. Race tracks are smooth.
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Jima4media
Posted on Monday, July 18, 2005 - 06:53 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Even if that front wheel weighed absolutely nothing, it wouldn't address the problem of actually stopping the bike quickly, which only can come from braking area on the rotor or rotors.

Sometime in 2000 Reg Kittrelle brought a Braking dual perimeter brake Buell S1 to Victorville and let us ride it. The stopping ability was outstanding, but the faster you went on it, the more centrifugal force was generated and the harder it was to turn, because the mass of the rotors was towards the outside of the wheel.

Kinda of like trying to turn a V-Rod.

The Buell XB12 has a 1320mm wheelbase versus the 1385mm wheelbase of the Yamaha R6 versus 1390 mm of the Suzuki GSX-R 600 versus 1395 mm for the Honda CBR600RR. Not a lot of difference in length. Yet the Japanese bikes all stop at least 10 feet shorter in the braking test.











(Message edited by jima4media on July 18, 2005)
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Jima4media
Posted on Monday, July 18, 2005 - 06:58 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Jon,

The reason brakes are a big deal to me is that the brakes on my 2000 Buell X-1 locked up on me three times. Two of those times resulted in crashes.

A Harley mechanic later admitted to me that they would mix up DOT 4 and 5 brake fluids from time to time. He said he himself had done it.
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Blake
Posted on Monday, July 18, 2005 - 07:32 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Alan (Chop),

You keep waving the race bike flag. I keep trying to explain that the benefits of the ZTL configuration and its resulting lower unsprung mass is much more applicable to a street-bike real-world scenario.

Why haven't the other manufacturers copied the ZTL? It is patented by Buell. Not the idea of a perimeter brake, but the precise way it has been achieved, implemented and configured by Buell. Have zero doubt, if Honda had thought of the ZTL first, they would be selling the out of it and rightly so.

You somehow imagine that the current repliracer wheel/brake assemblies have been able to shed 7 LBs of mass? Where? How? The ONLY weight savings I've seen is smaller diameter brake disks. That along with optimization of the overall structure maybe results in a pound or two at most. The ZTL wheel hub and spokes are practically nonexistant. A conventional wheel has a massive hub and spokes in order to carry the braking load from disk to hub to spokes to rim to tire.

"why do allllllll the race teams still go with dual discs from 1-800-Brembo?"

That may well be the best way to go for racing. Conventional wisdom certainly would say so. Then again, a ZTL config with carbon disk might prove even better. Why not run such a setup? Well there's that darn patent by Buell, the development time and money, and the stigma of having copied a competitor's innovation. Any or all work for me. Apparently you reject all the above?

are they just stupid and havent considered unsprung weight?

Pretty sure that is not the case. They did consider unsprung mass. Why else would they reduce their front disk diameters?

Is Erik Buell the ONLY one out there to figure this out? and everyone else is an idiot?

Not sure great innovation by one man makes all others idiots. I think it simply indicates that Erik Buell is simply more innovative. The way you choose to word your questions leaves little room for rational discussion. It's almost like you are out to belittle Erik Buell. Really unfortunate.

"These teams have millions on the line, trust me, its allllllll been taken into consideration."
That's a common belief which I know for a fact is not true, namely because it is impossible. Or are you proposing the current state of MotoGP or other racing motorcycle technology has reached a point where it can no longer improve? Motorcycle configurations will stay exactly as they are now, with only minimal improvements to performance and weight?

A racebike on a smooth well known track will not benefit near so much from the ZTL configuration as a bike on a bumpy country road.

How are you qualified to make a statement like "it's engineering for engineerings sake, not performance"? LOL!!! If you really believe that losing 8 LBs from the front wheel/brake assembly is engineering for engineering's sake, I have no hope of showing you how the ZTL is a real and significant leap forward in the world of street bike suspension and handling technology.

I guarantee you that if any of the Japan Inc teams had invented the ZTL configuration and recognized its huge benefit to reducing wheel unprung mass they would absolutely be marketing it and touting its substantial benefits.

But they didn't invent it. Probably because the brake engineer/designer and wheel engineer/designer are two different people looking closely at their own very specific little worlds. Truly magnificent innovation comes from an engineer/designer who is able to work with the big picture and how all the various parts work together.

I'd like to know the mass of whatever front wheel/brake assembly is lightest of all the repli-racers. I bet the Buell ZTL front wheel/brake assembly is more than a few pounds lighter.

In a world where the racing teams struggle, claw, and scratch to lose just ounces, that is HUGE.

To bad they don't own the patent on such innovative technology. Honda may have been close to it with their NAS concept bike, but even it didn't take advantage of the ability to shed a bunch of weight from the wheel. The Honda designers didn't see it; they only saw what looked to them to be a cool looking new type of brake disk mounting. How much you wanna bet they did feel a little stupid after seeing Buell actually release the ZTL brake/wheel system that same year. So close yet so far.

But I would never call the Honda sport-bike engineers/designers stupid.
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Blake
Posted on Monday, July 18, 2005 - 07:49 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Jim,
I guarantee you that the ZTL will stop any bike as quickly as any other brake configuration. It has WAY more braking power in reserve than you could possibly ever use. Let's be logical here okay.... If the M2's smaller single disk conventionally mounted brake system is able to score in the top ten in a braking distance competition, there is no reason if given a more optimum motorcycle configuration/wheelbase that a ZTL brake system would not do the same. A three inch shorter wheelbase is not the insignificant factor you choose to believe it is wrt braking performance. If you want me to show you the math, I will. It is pretty easily illustrated. Buell obviously chose the improved turning/handling performance of a front biased CG and shorter wheelbase over classs leading braking distance.

If I were to use your logic I would assume that asside from the R6 apparently all the other repliracers' front brakes are inferior to those on the Cyclone? Hey if that is the only measure of a braking system, they should all upgrade to that ancient Buell technology. Silly huh?

In one breath you say you are concerned about your brakes locking up because you have experienced that on three occasions, then in the next breath you indicate your Buell did so most likely due to having a mixture of incompatible brake fluids. : ? : ? : ?

BTW, when you say that your brake "locked up three times" I take that to mean that your wheel ceased rotation entirely. I kinda doubt that is what you mean though. Please clarify.
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Steve_a
Posted on Monday, July 18, 2005 - 08:32 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Braking performance of the XBs is limited by lifting the back wheel off the ground, not the performance of the disc. All current sportbikes stop at very similar rates with an expert rider on smooth pavement, and most racer replica types and Buell XBs are brakie limited. I doubt if the magazine brake numbers (including Cycle World's) significantly distinguish braking performance for this class of bikes. For example, the 60-0 brake number given for a given bike will be the single best stop achieved in a small number (3 to 5) of stops. The variation in stopping distances on that set of tests might extend over 10 to 15 feet. Statistics will tell you that using the best number for comparison purposes with such a small sample size is very questionable, particularly when the difference between bikes is relatively small. Basically, on smooth pavement with a single stop and good tires, all sportbikes, almost without exception, stop well. Also there is far more variation in rider performance than machine performance.

The ZTL front wheel assembly (wheel, disc, and tire) of the XB's is by far the lightest of any current sportbike. Including the difference in calipers, the Buell assembly is probably closer to 10 pounds lighter than that of most current sportbikes, including 600s. It also has lower rotary intertia, rather than more, as one not particularly technically competent, Hollywood-based, magazine guessed.
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Choptop
Posted on Monday, July 18, 2005 - 09:05 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

8 lb wieght loss over what?
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Choptop
Posted on Monday, July 18, 2005 - 09:14 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

yep that RC51 has a front brake and way heavy front wheel.

the same one that took honda to the ama championship.


Street OR race, if it were better, EVERONE would be doing it.

If there were REAL world, demonstrable benifits to the ZTL type set up, everone would be doing it.

Forget the race track... think sales.

If Honda did something like that and riders, testers and the general motorcycling public would see the benefit over another system, they would sell like hot cakes. we are talking millions in sales.

but that aint the case. Even for all the inovation Erik claims, and all the engineering advantages, the fact of the matter is that no one says, WOW did you feel that Buell front brake? Did you feel how absolutely reponsive the front end was? It beats every other bike out there hands down !!!!

It doesnt happen, because its not true.

The ZTL has one great feature, it comes in lighter than the state of the art superbike wheel from 6 years ago.

It doesnt offer the better overall package pure and simple.

if it did, everyone would do it for the sake of sales and racing.


and oh... not all race tracks are smooth, and even small ripples have HUGE effects when you are pushing it WAY harder than you ever would on the street.

Heck, even my old FJ 1200 front end feels great at street pace, so doen my 60's Triumph. Everything does. The true measure of an entire system is at its limits.
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Brianh
Posted on Monday, July 18, 2005 - 10:17 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Unsprung weight only matters when there are bumps in the road. Race tracks are smooth.

What race tracks have you been running on? I think I rode the bumpiest of them all this past Friday, Pocono East. Even Barber Motorsports Park has a few ripples from the cars in it. Nothing is perfectly smooth. The faster you go, the bumpier it gets.

Blake, there's obviously no point in debating with you over this. Ostrich's all over the planet are envious of how far you can burrow your head. I'm not trying to bash everything that Erik Buell said at the dinner either. I think he made some great points. I was very interested in hearing about how the company addressed the quality issues. I was happy to hear an almost honest assessment of where the build quality was for the tube framers. I loved hearing how improvements were made from the RR's to the S2 to the S1/S3 and X1 models.

Realize Blake, the lord Erik Buell himself admitted in front of the room that the quality control issues with the tube frame bikes left something to be desired. You defended those machines, still do, in the same manner you're debating the ZTL. It's great that you love the bikes this much. But you really should take the rose tints off for a moment.

I didn't appreciate how Mr. Buell dismissed radial brakes, horsepower, and everything else non-Buell. How can he make those statements when he hasn't actually built anything better. For all his engineering talents, time, and money, Buells are incapable of competing on a racetrack outside of race series designed specifically for Buells.

Can you imagine a Buell at Daytona? I'd give it 10 laps before it exploded. Most teams bring race rubber and qualifying TIRES. Buell brings race engines and qualifying engines. They go through motors like most bikes go through tires.

For those of you who feel that the XB front end provides some sort of superior feel, I challenge you to go ride a modern 600 or liter bike. I put about 1000 miles on an R6 recently and I've got to say that it's a total scalpel. That bike feels great. I did a track day on my F4i afterward and it felt like I was riding a sport tourer. I NEED an R6 now. XB's can't compare. It's that simple.
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