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Buell Forum » 1125R Superbike Board » Archives 001 » Archive through April 14, 2011 » 1190RS Front Brake Rotor- Interesting! » Archive through February 26, 2011 « Previous Next »

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Jdugger
Posted on Friday, February 25, 2011 - 10:45 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

> 'cause let's face it, ECR don't look like MONZA

Doesn't cost like it, either.

Eagle's Canyon has been around a few years now. Like most of the road courses in Texas, it operates on a combination of country club + events business model.

I use my membership a lot, so my actual cost-per-day is relatively low, at least compared to typical track day fees.

Nothing in this sport is cheap, that's certainly one of its drawbacks.

You have Hallet near you that does tracking days for around $100 per day at least a couple of times a month, and RideSmart and other public track day orgs run at ECR frequently, so you can get on the track that way.

Or, just drop me a PM. The guest fee for a member day is "a Jackson or two" more expensive than the typical public track day, but you get both more track time and drastically fewer bikes on the track at once.

When we were testing our endurance bike we took this video of me riding our CBR600 with plain 'ol street tires and OEM brakes. I was the only one on the track.

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Gas
Posted on Friday, February 25, 2011 - 10:52 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Damn, that looks like fun.
Pavement looks as patchy as Hallett, where there are 75 bikes for every track day.
But...where are the TREES? It looks like the SEA of TRANQUILITY!
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Jdugger
Posted on Friday, February 25, 2011 - 10:55 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

> How much of your braking is dealing with other riders?

I can't speak for the really fast guys, but at my (slow for a racer) level the answer is some, but not much.

Once you make the first few passes (or simply start in a better grid position because of points), you are left with riders ahead of you roughly equal in skill. So, while you might be braking a bit more for someone slightly slower that you just can't get around, it's still about the same as you would do on your own.

> There are all kinds of braking, what is your IAC decel setting?

Mine is set for a very generous off throttle fueling. I prefer to use the brakes to stop, not the motor.

> Throttle off with full IAC decel would be just like grabbing the brakes,
> it would slow the bike down hard. More engine and less rotor?

Not at racing speeds. Engine braking, even if set to be as much as possible, isn't very good at setting vehicle speed compared to the front brake. Depending on the motor to slow you down will absolutely land you in the run off or in the back of another rider. If not, you are entering the corner so conservatively slow the entire field is going to pass you.

I don't think many street riders realize just how much race pace demands of the brakes, and just how much speed can be shed on a modern superbike with the front brake. I'm dropping close to 90 MPH in just 200-300 feet going into turn 7, for example, and I'm not even that great of a rider.

Again, this is the opinion of a mid-pack novice racer. Get into the experts or, gasp, AMA level, and it's everything I'm saying to a much larger degree and to really an almost unimaginable level.
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Torquaholic
Posted on Friday, February 25, 2011 - 10:55 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Living in College Station, I've been on TWS and agree with Jim about the high speeds. Overall, it is a high speed course but not too technical. Too bad there's tar snakes everywhere. I'd like to ride on a nice surface for a change.

I'm a slow rider by my own standards, but I hit 14x indicated crossing the checker on a cold February morning last year. Racers I've talked to also state the 150/160mph speeds near the end of the main straight.
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Jdugger
Posted on Friday, February 25, 2011 - 10:56 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

> But...where are the TREES?

Away from the run-out!

We perfer giant slabs of shale and limestone instead!
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Rodrob
Posted on Friday, February 25, 2011 - 11:20 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I had the 5mm finned rotor with EBC race pads. The pads wore out quickly and I found myself without spares on race day.
Shawn Higbee gave me an old set of his EB R 2015 compound pads to use. The difference was like night and day. Firm feel, great grip, no fade. Now, Shawn brakes really hard and has to charge most corners to keep pace with the more powerful IL4 literbikes and these pads have lasted for a season and a half for him.
If you have not tried these pads, I would suggest doing so. They are worth every penny IMHO.
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Drawkward
Posted on Friday, February 25, 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)

Torq: Come down to GrandSport Speedway with Fastline March 19th...REALLY good pavement there. It's a slower track and not as fast but probably one of the most technical in Texas.

And not to be a nutswinger here, but I agree with literally everything JD is saying.

It seems the real disconnect is with guys who are actually racing this 1125R platform or doing trackdays once a month, and guys who are pushing pencils.

Blake/Court, take JD up on his offer and come back and tell us what you think.

I am getting gold/blue rotors with EBC race pads and RBF600...STILL getting fade with that set up too. It makes me so mad that I have to buy a new rotor and hardware, race pads and possibly a new MC to have a brake system that consistently works (and I'm not as fast as JD). It's a good thing the damn bike is so fun to ride.

Rodrob: Good insight there...may have to consider them. They sure are expensive though!!

(Message edited by drawkward on February 25, 2011)
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01lightning
Posted on Friday, February 25, 2011 - 02:56 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I mangled my hardware and rotor pretty good last year. I was going thru front pads like water-even pulled off track once because I felt a chatter when i knew i had plenty of pad left. Thats when I saw the twisted hardware and realized I had a problem. Unfortunately, I discovered that the session before my mock race while going to race school. If ya crash during the race, no license. I did the race but parked it until my new parts arrived.



I got the Erik Buell Racing 5 mil race rotor, new hardware and the performance friction pads. I was a little short on dough and couldnt quite afford the 2015's even though they were only $35 more. It was either wait, miss a track weekend and get the 2015s or get the PF pads and dont miss a weekend.
HUGE difference. The braking was better, more consistent and just felt better. I havent put enough time on em to speak to their endurance yet but I know with the stock pads and fluid I would easily be able to tell how worn the pads are based on the lever travel. Havent experienced that yet with these but as I said,no real time on them.Fluid is Motul.
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Jdugger
Posted on Friday, February 25, 2011 - 03:20 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

01,

As you discovered, the drive bushings are a bit of a weak link in the brake mounting system. They were especially prone to shear and wear when using the OEM mounting hardware.

The Erik Buell Racing mounting kit makes a tremendous difference, but it's still very critical to keep an eye on those things. They absolutely do wear.

Also, sometimes the Erik Buell Racing kit will introduce a little bit of shudder in the disc because it holds it so firmly. What I do is use thinner copper heat sink washers on the mounts that drag in the brake until the rotor has enough play it won't bind up.

You can also use thinner belleview washers, and use one on top and behind the rotor, or use a thinner washer for the zinc-plated one that normally bears the rotor itself on top. That will give the rotor mounts more "play" to work with.

The torque of the rotor mount bolt is held against the top-hat bushing, so it's somewhat "ok" to have the rotor rather looser between these.

One of these days I'll put together a list of McMaster part numbers to keep handy as a "racer's brake hardware kit". It will include various thicknesses of copper washer and belleview/spring-disc washers to optimize the brake.

If your wheels aren't spot-on perfect -- and *both* of my Erik Buell Racing cast Mg ones aren't -- it makes a difference.
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Blake
Posted on Friday, February 25, 2011 - 03:31 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

In only its 2nd race outing of 2008 and piloted by rookie superbike racers, the 1125RR was seen battling Larry Pegram on his Ducati 1098R for 4th position.

Last year, Geoff May entered twelve AMA Superbike races on the 1125RR. He finished top ten in eight of them, top six twice, led one, all on a significantly underpowered 1125RR with less than optimum aerodynamics.

Though riding a significantly heavier bike, Danny Eslick was repeatedly seen outbraking his competition and blowing by them in the turns (recall the passes on Cardenas and Hacking) on the way to winning the 2008 Daytona Sport Bike championship on the RMR Geico Buell 1125R.

The Pegasus Racing Team with mega-man-sized 1190RR racer Harald Kitsch, manager Jens Krüper, owner Thomas Wanner, chief mechanic Christian Hoffmann, engineer Alex Kucis, and associates won the German Twins championship walking away, and they won the final open superbike race by 7.5 seconds against a field of Ducati, BMW, KTM, Yamaha and more superbikes.

I guess the braking was holding them all back. :/

My guess is that if the ZTL concept works well enough to do all that and continues to see significant further improvement, it may be a worthwhile to continue using and developing.

I'm not sure what you are so determined to bring to light in every thread where brakes are discussed, that the brake gets hot? I think the continuous and significant development over the past three years, now including ducting aimed at the very issue of heat dissipation confirm your assertion that the brake gets hotter than desired. Who is denying it? : ?

What is the point you are trying to make?

I have the wool pulled over my eyes? : ?

What would you call it when someone refuses to acknowledge the benefits of a 6 LB reduction in unsprung mass at the front wheel/brake assembly?

Apparently you don't appreciate that. Seems really odd. Why do I bother to offer my view in counter to the incessant naysaying against the merits of Erik's perimeter brake system? I just prefer to not see the 1190RS front brake topic polluted by yet another irritating round of indignant criticism. Why? It belittles the efforts of really good people who are putting themselves WAY out there and actually accomplishing great things. See above list of racing accomplishments.


A 1:58 at ECR on your 1125? Sounds like a good pace to me. What is your best lap there on the endurance machine?

On the XBRR at TWS, Jeremy McWilliams was hitting 172 MPH coming into turn 1, then braking to 90 MPH or so. Mike Cicotto was right there with him just a few MPH down. I was holding the radar gun and recording top speeds.

I had a chance to ask Jeremy what his impression of the front brake was. He said it was closer in feel to a MotoGP brake than a Superbike brake. I asked Mike Cicotto and Dan Bilansky and Steve Crevier the same. None of them had any complaints about the brake. Steve's answer was a "you know, I didn't even think about the brakes when I was out there."

That was back in, what, 2005?

Pegasus Race Team has some great on bike video of the 1190RR devouring Ducatis and others.

http://www.youtube.com/pegasusraceteam#p/u/1/AxjRw Epwikc

I like this one, qualifying at Assen, great sound, blows by Ducatis like they are running on one cylinder...



With the ducting, the brakes don't seem to be a problem there at all.
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Ysracer
Posted on Friday, February 25, 2011 - 03:33 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

One correction JD, they're "belleville" washers.

Might be important to watch the material used, due to heat limitations. 17-7PH stainless is rated to 550 deg F, 6150 or 1074 carbon alloys are rated to 350 deg F, Inconel 718 is rated to 1100 deg F, and H-13 tool steel is rated to 795 deg F. However, given that in this application the springs are completely flattened (IIRC), it may not matter much if the spring rate is affected by heat.
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Blake
Posted on Friday, February 25, 2011 - 03:44 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 why anyone would be running EBC pads on the track on a Buell. My own experience racing with them on my Cyclone was disappointing as well. Use the good stuff recommended by the pros at Erik Buell Racing.
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Blake
Posted on Friday, February 25, 2011 - 03:53 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I'd not be modifying the Erik Buell Racing brake mounint willy-nilly based on guessing what may or may not be happening or what may or may not be okay. Especially with magnesium wheels.


quote:

sometimes the Erik Buell Racing kit will introduce a little bit of shudder in the disc because it holds it so firmly. What I do is use thinner copper heat sink washers on the mounts that drag in the brake until the rotor has enough play it won't bind up.

You can also use thinner belleview washers, and use one on top and behind the rotor, or use a thinner washer for the zinc-plated one that normally bears the rotor itself on top. That will give the rotor mounts more "play" to work with.

The torque of the rotor mount bolt is held against the top-hat bushing, so it's somewhat "ok" to have the rotor rather looser between these.




JD, How do you really know any of that for sure? Surely you can see that there may be a number of possible causes of the shudder you mention, and also a number of unforseen effects of your washer recommendation. I think experimenting is great, but I'd be careful about making such firm statements and recommendations.

If the bushings are wearing prematurely, sounds like they might need to be larger diameter. They do seem on the small side.
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Blake
Posted on Friday, February 25, 2011 - 03:56 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

This would appear to be the latest optimum solution for racing applications of the Buell front brake system...

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Jdugger
Posted on Friday, February 25, 2011 - 04:05 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

> One correction JD, they're "belleville" washers.

Doh! I always mess that up. Might have to start referring to them as disc springs.

> However, given that in this application the springs are completely flattened (IIRC),

They more or less are. I can also tell you even the original Erik Buell Racing parts from the kit after a session loose their spring. I always put a fresh washer on whenever I service the brake, but I've noticed those coming off are "unsprung".

Where you get into trouble with the Erik Buell Racing kit is if your wheel's rotor mount tabs aren't spot on. Both of my wheels have a drift of about .010, so I shim with the underlying copper washers accordingly. This gives the rotor a little bit of play (mind you, to the hand, it's still "tight" and rigidly mounted), but makes a huge difference when things get hot and you would otherwise have the chatter from the inside of the rotor.

> I don't know why anyone would be running EBC pads on the track on a Buell.

The EBC 4-HH (extreme pro) aren't half bad, and I actually prefer them to the performance friction pads sold by Erik Buell Racing which require a LOT of lever pressure relative to softer pads. I vastly prefer both the Nissin and Vesrah options to those, mind you, but the EBCs aren't just absolutely horrible. Like tires, brake pads are subject to personal preference.

EBC also makes a couple of other compounds, so perhaps that's what you have experience with? Certainly the street compound isn't race worthy.

And, Blake, no one is here basing the Buell. We are Buell racers for goodness sake. We are saying it's not all pink Kool-aid. It really is OK if the Buell isn't best at everything, it's a great package all around.

And, as you know, Eslick benefited from a couple of things: 1. He had some upgrades to his braking system that are only now becoming known and available, and 2. well, he's *ESLICK*. He's a "local" kid to these parts, a great racer, and he has me cheering for him no matter what he's on!
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Ysracer
Posted on Friday, February 25, 2011 - 04:05 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Agree 100%, Blake, but the funny thing is that you are now on board with the incessant naysayers. Because, you see, EBC Extreme Pro pads are a viable option for a Honda/Yamaha/Suzuki, et al. I have friends who use them and get half to a full season from them for A group trackday use. They do not survive even one day for me on the 1125. I am roughly 2 seconds per lap quicker than them, but that does not account for the vast difference.

I do get the points you made above, and agree that the weight saving of the system is a plus, and the constant effort and resultant improvements are appreciated.
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Jdugger
Posted on Friday, February 25, 2011 - 04:17 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

> What would you call it when someone refuses to acknowledge the benefits of a 6
> LB reduction in unsprung mass at the front wheel/brake assembly?

I don't refuse to acknowledge it, but I also know that better brakes are worth more than a lighter front wheel in racing applications.

For what it's worth, we have weighed my wheels against other race bikes, and the savings just aren't that great. In particular on the rear wheel that heavy cast pulley makes the rear assembly quite a bit more heavy than competing chain-driven hardware. The front wheel is only a couple of pounds lighter when we put stuff on the fisherman's scale, and one ZTL caliper weighs about the same as their two.

Man, I've been through this. Get out your scale, go grab a late model R6, ZX-6, CBR600RR, and start doing some weights and measures. You are in for a bit of surprise. The Japanese makes have come a long way with their OEM wheels, and the Buell wheels are still circa 2002.

It will be interesting to compare the new 1190rs wheels, though. That's essentially the first update to a Buell wheel system in a decade. I am exited about it and have high hopes for it.

> A 1:58 at ECR on your 1125? Sounds like a good pace to me.
> What is your best lap there on the endurance machine?

Mid 2:00. I'm about 2 - 2.5 seconds a lap faster on the Buell, but the Buell is putting down 40HP more at the rear wheel and weighs just a titch more. (our 2003 Honda CBR600RR endurance bike is completely BONE stock.)

Riding the Buell is a lot more fun, but it's a *workout*. I can't imagine trying to endurance it!
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Jdugger
Posted on Friday, February 25, 2011 - 04:30 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

> JD, How do you really know any of that for sure?

I don't for sure, but my recommendation puts the drive bushings and rotor mount bolts at no greater load or sheer force than the OEM setup.

Measure the OEM bolts vs. the Erik Buell Racing bolts and the distance the rotor is held off the rotor mount points on the wheel to get a feel for what I'm talking about.

I have the same concerns you do... it's MY butt on the track : )

> Surely you can see that there may be a number of possible causes of the shudder you mention, and also a number of unforseen effects of your washer recommendation.
> I think experimenting is great, but I'd be careful about making such firm statements and recommendations.

Warning heard, appreciated, and accepted.

> If the bushings are wearing prematurely, sounds like they might need to be larger diameter.
> They do seem on the small side.

That's a Buell thing, it's their drive bushing and assembly. Using the OEM hardware, they were very prone to shear and twist up because there was little to help them stay square within the drive bearing face of the rotor. So, the bushings tended to slip out a bit and only support the rotor with "half" their edge/body or less. The pics that 01 posted are a perfect example of what happens with a good rider gets on a Buell with the OEM kit and uses the brakes. That sort of stuff was happening to me in my first weeks as a new track rider, and happening all too frequently, too. I have a garage full of rotors that are carved up like O1s. I've posted about this before here, and how to check for it at length. It's a serious service item on stock Buells.

The Erik Buell Racing hardware VASTLY improves this because the amount of natural "float" the rotor is allowed to have is substantially reduced. However, I've found that of about half my sets of wheels I own for the Buell (I have 6 sets, don't ask why), have a run out at the rotor mounting point of about .010. Now, this wouldn't have mattered with the old OEM kit since the rotor is held AWAY from the wheel. But with the new approach, the rotor is held closely to the wheel with a disc spring against the copper washer (to dissipate heat), and if the wheel is out of line at all that wheel shudder ends up in the brakes, hence the need for different thicknesses of copper washer under the rotor to compensate.

I've have been through this exercise so many times now with my DTI, I am quite confident in it. My wheels are marked so I know how far in/out each rotor mount point is so I can get that smooth, grippy brake feel of a brake perfectly in-line.

The cheap cast wheels these bikes come with don't have the tightest of tolerances, and more than once I've thought about having a good machine shop ever-so-slightly mill those rotor mount points true.
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Blake
Posted on Friday, February 25, 2011 - 06:56 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I was just going to suggest that. True 'em back up.
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Xoptimizedrsx
Posted on Friday, February 25, 2011 - 08:23 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Those equations are correct.
Each work with a different aspect of the whole picture.

Just which one is incorrect? not (omega) or delta nor force.

not even the distance or inertia are incorrect.

speed over distance is fixed over the radius (total Diam) if you can change that on a solid object your the man/woman and I am sure many others want to see how you did it.

simple online search proves it many times over. look here...
http://dev.physicslab.org/Document.aspx?doctype=3& filename=RotaryMotion_RotationalDynamicsRollingSph eres.xml

how many was wrong on what was faster solid or hollow?

More advanced looks at it here.
http://www.electron.rmutphysics.com/physics/charud/scibook/Physics-for-Scientists-and-Engineers-Serway-Beichner-4/11%20-%20Rolling%20Motion%20and%20Angular%20Momentum.pdf

See page 337 and 338 in above link pasted in browser.

guess these physicist are wrong on the FX as well especially circular motion?

The ducts are a great improvement in any discussion... Erik Buell Racing has his stuff together we can all agree on that.


(Message edited by xoptimizedrsx on February 25, 2011)
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Xoptimizedrsx
Posted on Friday, February 25, 2011 - 09:37 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

http://www.khanacademy.org/?video=centripetal-acce leration--part-3#Physics

all yours now. have at it...
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Blake
Posted on Saturday, February 26, 2011 - 12:31 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Mike,

>>> m1+v1(m2+v2)before=m1+v1(m2+v2)after

Not sure what you mean by the above. Looks like a messed up equation to me. Each side reduces to...

m1+m2v1+v1v2 (mass + momentum + velocity squared) : ?

which as Anony notes, makes no sense.

Your mass moment of inertia equations are correct in and of themselves, but your argument for a disk wheel assumes the same mass as a ring configuration, whatever that is. You do need spokes, yes? If you can take the mass of an XB front wheel's spokes and turn them into a solid disk, you'll have done something impressive, but the inertia will be the same, or most likely increased. The spoked wheel is not analogous to a ring. The spokes run from almost r=0 to r=R, just like the material comprising a solid disk. In fact, the spokes taper as r increases so having less mass as r increases. Which means that you got it backwards I'm afraid. The spoked wheel has less inertial.

By P=W/t I think you mean that power equals work/time_interval, which in engineering math-speak would be P=W/Dt. I agree that neglecting the effect of aerodynamic braking, the DKE=1/2m(V12-V22) will be roughly equivalent to the energy absorbed by (work done by) the brake.

Odd, the greek symbols aren't working. Take "D" to mean "delta".

I think I understand what you are saying about the larger diameter rotor benefiting from a more consistent swept surface versus smaller rotors.

I think cooling ducts for the caliper may be just as much for overcoming a rearward facing caliper (open side of conventional brake caliper faces into airflow where the Buell caliper opening faces aft) that is also largely shielded from cooling airflow by the fork leg. The Buell ZTL style rotor may also be shielded more by the tire. Might be a future evolution to see the disk move outboard just a little maybe, or to see a tire with a smooth transition from tread to sidewall to help keep the flow attached and better able to cool the disk.

I agree! Physics is fun! : D

I'm guessing that F=mV2/r would be your interpretation of the centripetal force acting to send you off track in the midst of a turn after tucking the front?

The f=1/2gMV^2 seems to be an odd combination of ... heck I dunno. The units sure don't work out to force. Lowercase "f" signifies tensor stress in civil/structural engineer-speak; uppercase "M" may be momentum (mV). You likely meant F=1/2gmV2? I still don't follow.

FYI: Bicycle racers use solid wheels for the significantly improved aerodynamics, not anything to do with inertia.

(Message edited by blake on February 26, 2011)
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Jens
Posted on Saturday, February 26, 2011 - 07:34 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I fight that ZTL battle now since 2003. In the end it is as simple than this:

You win - you right (-:

Jens
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Reepicheep
Posted on Saturday, February 26, 2011 - 09:08 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

: )
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Dannybuell
Posted on Saturday, February 26, 2011 - 09:59 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Blake does math and science too. :-)
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Xoptimizedrsx
Posted on Saturday, February 26, 2011 - 10:33 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

m1 • v1 + m2 • v2 = m1 • v1' + m2 • v2'

The symbols m1 and m2 in the above equation represent the mass of objects 1 and 2. The symbols v1 and v2 in the above equation represent the velocities of objects 1 and 2 before the collision. And the symbols v1' and v2' in the above equation represent the velocities of objects 1 and 2 after the collision. (Note that a ' symbol is used to indicate after the collision.)
(this is what I meant)

Note: above copied from online physics source.

PE=KE which is directly proportional.

centripetal Force F=mV2/r
A center seeking net force that is required to keep moving objects in a circular path. If the requirement is not met the object/s move in a larger curved path or go off on a tangent. yes tuck a wheel low side and poof off you go.

you will use two tangents: one is in a fit human style. lol,the other physics.

all I want to know is when are these parts going to be available from the 1190. This way I can get three break coolers for my bikes as well as a few others.
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Xoptimizedrsx
Posted on Saturday, February 26, 2011 - 10:52 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

solid wheel vs spoke wheel.
If mass is evenly spread out the solid wins.

If the spoke is designed where the center Axel area is the greatest mass and tapers outward, then the inertia will be less on that wheel and it would win hands down. But not all spoke wheels are created like this. A Buell wheel is one that is done this way.

In anyway, form or type, if you center the mass and you got something good.

smooth is fast, cool is fast and the 1190 is a smooth cool bike. Therefore, it will be fast...
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Blake
Posted on Saturday, February 26, 2011 - 12:25 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

I see, conservation of momentum, that is now a correct equation. Not sure how it applies to ducting, or braking.

>>> If mass is evenly spread out the solid wins.

I don't see how. In reality the mass of a solid wheel is concentrated towards the perimeter. With spokes the opposite is true. With cast or forged spokes integral t the wheel, it's much less so. The solid bicycle wheels are for much improved aerodynamics, not anything to do with inertia.

>>> But not all spoke wheels are created like this. A Buell wheel is one that is done this way.

All sporting bike, heck all sport oriented moto wheels are like that as far as I know. Only wheels I've seen with spokes that might expand in section as they approach the rim are goofy stylized chopper wheels.

The reason is that the loads in the spokes, especially for conventional hub-mounted brake rotors, are much higher nearer to the hub.
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Xoptimizedrsx
Posted on Saturday, February 26, 2011 - 02:06 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

just roll two objects down a incline. hoop vs solid test.

same mass same diameter. solid picks up speed quicker.

on the bicycle wheels, those were test objects last year in class. every solid wheel got up to speed faster as well as aerodynamics. a win win for the solid wheel is controlled test. I was the one whom picked the hoop design at first to roll faster back then on equivalent mass and diameter. I was wrong...

relates to the old merry-go-round test. If your at the center and its spinning at the center at 45 rpm its spinning at 45rpm throughout. now move yourself out to the middle your speed increases even though the rpm is the same. speed in distance covered. then move to the out side. you increase even faster and possible fly off (centripetal). even though its still at 45rpm the distance covered is proportional to the diameter.

flip this to braking... larger diam rotor gives more surface area for more refined breaking over smaller disk at the same rpm making the larger one stop more quickly with less force "I would think". It would take two small disk to equal the one Buell rotor.

I picked up a couple pointers from these post as well. I wish I had more physics based people around locally to grow knowledge besides books. real world usage...
(Thanks Blake your knowlege does help in the picture for me.) You stepped up to the plate to explain, whereas others post comments not helping anyone. Just negative thoughts and comments doesn't help anyone.
I would rather be incorrect and put in my thought in than post your wrong and poke at someone without helping by correcting if I knew the answer 100%.

example:

like 1+3=5
comment
you made me laugh
thats stupid and so on...

comment would look better like this.
no that would be wrong or (incorrect)

correct would be 1+3=4
and give why if needed to clarify something. even post a link to help explain if possible. (like Blake does)

Thats how people learn... never stop trying and/or learning...

needless to say; the bike "1190rs" is still sexy beast with good brakes...
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Dcmortalcoil
Posted on Saturday, February 26, 2011 - 09:08 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

In the above scenario, the hoop would have to have a greater moment of inertia since they have the same mass. That is, the hoop configuration has more mass is at the outer periphery than the solid configuration.

Lower moment of inertia is the reason for the solid accelerating faster.

Right or wrong?
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