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*Liam's Wild Ride*

Hey everyone, quiet day for me.

Nice to watch the races this past weekend, and get my fix! Fantastic run for the Repsol Hondas in Shanghai, and who could have thought that a mechanical DNF for the doctor was possible? Actually, I think it's incredible that a front tire from Michelin failed, and in spectacular fashion, too, ripping the front fender off the bike. That's two races in a row where tires have failed, and from both major brands in the series - Hopper's rear Bridgestone in Turkey, Rossi's front Michelin in Shanghai. Obviously, the tire companies are stepping it up to try and best each other, and it seems like there's new advances coming quite often. I hope it doesn't mean that there will be more inconsistencies like what we've seen, because I don't like the idea of tires taking charge of the Championship. But that's racing. Lots of speculation about the Frame being the source of trouble for the Camel Yamahas, as well, and I have know idea who to listen to these days. I've heard every version of the story, but the bottom line is that no matter what, Rossi seems to be able to put it together on Raceday and take care of business. I also want to say that it was a nice day to be an American fan, as we had 3 of the top 4 finishers in MotoGP!

I will be headed to Le Mans GP later this week, to experience the French life. . . and I may have access for two . . . . so if you're going to be there, get in touch!
 
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Good catch. Didn't even notice that the chunked tire ripped the front fairing off. Amazing... That was a pretty big hole - about 10 x 4cm. Lucky that he made it into the pits and didn't get hurt out on the track riding through it.

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I heard that tire makes were able to come up with prototype tires quicker by refining the manufacturing process. Hope they're not sacrificing quantity with quality.

I don't think it was a manufacturing problem, though. I think Rossi just rode the thing too hard too long. He made up 8 places in 16 laps and was hot on the heels of Hopkins and Edwards. If his tire didn't fail he would have easily passed those two and made it on the podium.

I hope we don't see too much of tire war. I think when things are consistent and even that provides the best racing. Just check out WSB. The control tire revitalized that series. Hope it doesn't have to come down that. The drop in engine capacity should help relieve the pressure tire manuf are put under.

It makes sense that too stiff a frame could cause the chatter problems. The vibrations would resonate throughout the frame compromising handling. A "softer" frame would cushion or absorb the vibes. This phenomenon worsens with the qualifiers. But what exactly is ttire chatter? And is it possible to install some sort of vibration dampers in/on the current frame to reduce it? Something like this:

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These are found on Subaru S204s and dampen the lateral vibrations caused when carving turns. It allegedly enhances handling. Plus, it's made by Yamaha!
 
sarawalker said:
High res image of Rossi riding bike w chunk off of front tire

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I bet we see this photo in almost every mag that covers road racing in the next few months
 
dypeterc said:


I don't think it was a manufacturing problem, though. I think Rossi just rode the thing too hard too long. He made up 8 places in 16 laps and was hot on the heels of Hopkins and Edwards. If his tire didn't fail he would have easily passed those two and made it on the podium.

I hope we don't see too much of tire war. I think when things are consistent and even that provides the best racing. Just check out WSB. The control tire revitalized that series. Hope it doesn't have to come down that. The drop in engine capacity should help relieve the pressure tire manuf are put under.
[/B][/QUOTE] Hi Guys.

Well i suppose no one said it was going to be easy. What a year Vale is having.

When he said a Girlfriend is worth 2 seconds a lap which way did he mean? (Sorry Vale)

But seriously Tyres or should i say Tires? Last year everyone applauded the leaps that the tyre manufactures had made in grip, especially in the wet. This year they seem to have moved their performance up even further with grip levels allowing riders to achieve outreageous lean angles. The Chassis and suspension seems to be over loaded at the moment though and is dissipating the energy through movement/vibration (Chatter) which in turn is dissipating through heat and seems to be the reason for the faliures seen recently at the front just as the increased power at the back caused faliures there. On the plus side though i feel that the problems are fixable and that a way will be found to sort it.

As for frame stiffness my altime favorite quote was from South Africain GP star Kork Ballington in the seventies when he claimed that his Kawasaki Monocoue Frame was too stiff. A thing that i thought was just not possible to have a frame that was TOO stiff.

It was great to see Vale at the top of the timing sheets in the wet after his poor showing in Turkey. (Even if it was short lived) Well done Danni, Nikky and Colin not forgetting the great performance from the Hopster which shows the significance of a change of management.

Changing the subject after hearing how Randy misses the transatlantic series and realising the logistical problems that would bring to set aside the easter weekend for most riders i thought that you could encorage some inter disipline rivalry by having a manufacturers series that uses naked muscle bikes straight off the streets as a suport race, the only adaptations they would be permitted to make over and above the genuine street models would be to fit Slicks and a sticker over the lights. Riders from all disciplines could take part as their scedules permitted to a maximum of say six per manufactuer. Being manufacture based would allow the rider line up to change allowing the cultral make up to change with the lolcation it would also allow veterans to be feilded so they could stop saying they would have been better than so and so and actually be better than so and so (Or not)

I used to love watching the old superbikes being musceled around by real men and would love to see it again.
Click to expand...
 
Lots to think about here, about tires, frames, WSBK, and more. . . . . .

I'm not sure where to begin, so I'll start with GP tires first. I disagree that Rossi's tire failure was caused by him "riding too hard" and making up places. I think it was purely a fluke incident. Pedrosa's and Hayden's tires held up fine, and their pace was little higher than Vale's. Some background for the people who aren't fully aware of what's been going on with Rossi's ride. Last year Michelin brought out a new, wider rear tire, which everyone loved. This year, they brought out a wider front tire, which the Honda guys liked, but that Rossi didn't. He continued to develop the '06 M1 with the "skinnier" front and fat back, and possibly this is what led to him to misdiagnose the handling issues with the latest M1. I think the chatter problem's Vale was suffering from could have been due to the increased traction of the fat rear tire "pushing" the front and causing the front to oscillate back and forth. After Instanbul, Rossi started working with the fat front tire, and immediately noticed that the settings weren't right for this tire combination. Everyone said, it's the rear shock setting, but there's more to it than that. A new Chassis will be at Le Mans, and while it may be stiffer in some areas, I don't know if it will be the version that is used for the rest of the season. Some riders prefer flex in their frames. . . as evidenced by Capirossi and Checa running slightly different frame configurations on their GP5's, or Colin Edwards' 2002 season in WSBK, where he made a revelation at Laguna Seca that helped him dominate the second half of the season to take the championship. His secret? Removing an engine mounting bolt on his RC51. I don't think a frame dampner would help in this situation, as the manufacturers just make things to varying thicknesses to achieve the stiffness they want. If you look at swingarms, they're very stiff front to back, but flex side to side. Frames are set up in a similar way, but the damper is an interesting idea.

I also think that changing the engine size next year does not automatically mean the tire makers will have an easier time. I think cornering speeds will be even higher, so side grip is going to be of vital importance for the duration of a race. And the bikes are going to be just about as powerful as they are now :( Wait, that's a good thing :)

Speaking of tires, while the control tires in WSBK have evened up the playing field, it appears that it's now just a matter of traction control. Everyone running towards the front is using it, and it looks like some people have set theirs up better to work with the Pirelli's. On the AMA side, it's interesting to note that the finishing order is reversed. WSBK = Ducati 1st, Suzuki 2nd. AMA = Suzuki 1st, Ducati 2nd. Could this be because of the time spent working on things with Dunlop? And who still thinks that traction control isn't in the AMA? Does anyone know what the software looks like? Could a tech inspector spot the difference between just ordinary telemetry sensors, and, well, telemetry sensors? :laughing

It's fantastic technology on the track, but is it really racing anymore? One thing is for sure, there will be a trickle down effect for streetbikes. Who wouldn't want to run a bike in Supersport or Superstock with traction control - because it came off the showroom floor like that! I think that after being around some of this stuff, I'll stick with the simple things. I want my next bike to be kickstart only, with a bitchy carb in the mornings!

This morning I managed to get out for an hour and a half, bicycling along the coastline while I watched the city wake up. Dang graffiti!

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Found a couple of ramps along the route, and behind these there was a nice pool to drop in and out of. I wasn't wearing full gear, and I didn't get out on the bigger stuff. Another time.

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Last shot for now, showing a neat overpass above the freeway. That's a mall across the street.

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Of course a Pink watermark! Good to see you're gettin' out on the bike, now I want to see some "action" shots!:laughing
 
In the good aftermarket ECU's, traction control is as simple as "check this box" and then go set all the slip ratios. In that case, it would be very simple to see if it were on or off. Although I suppose that some of the superbike teams are high enough on the totem pole to be able to tell their ECU supplier to write in some hidden code somewhere- a tech inspector would not really be able to check that easily, without requiring a spec ECU. It is possible that they could require the code to be the same version throughout the season and they could approve it at the beginning, but after seeing the simplicity of the regulations I really doubt it. Is there a wheelspeed sensor on the front wheel of AMA bikes? I've never noticed one, and its needed for traction control.

Back in the days of restricted traction control in F1, there were rumors that Ferrari was using a pitot static tube for slip ratio control. A pitot tube is whats on an airplane to measure airspeed through pressure differences. Many teams now have pitot tubes on their noses, but traction control is legal. Who knows what they use them for- possibly just documenting the downforce compared to airspeed, since a headwind affects downforce and isn't seen in wheelspeed.
 
Frames are set up in a similar way, but the damper is an interesting idea.
Click to expand...

Yamaha did actually test a frame damper system on an M1. It was on Abe's bike a couple of years ago.
 
Reading the article at http://speedtv.com/articles/moto/motogp/24313/ confirmed what I was thinking you guys were referring to as "chatter" (assuming the writer knows what he's talkign about). The frame has a resonance at a certain frequency, and they are hitting that resonance with whatever tire/engine/suspension settings they have. A natural frequency and harmonic resonances are difficult to mathematically predict- I know that we don't even give it a thought in any of the designs I'm involved with. But if you happen upon that frequency in use, terrible vibrations or worse can occur. It's not a stiffness issue- just the natural frequency of that particular design.

A frame damper would help solve the issue, but really the best way is to just change the frame around a bit, which is seems like they are doing. The problem now is that the current frame is what they came up with as the best design, and now they will have to throw some part of it out to change the natural frequency. Will the now compromised frame be a step back from the previous, or is this a chance to let out the next, better design iteration?
 
FC Barcelona!

I don't know about where you live, but when this city wins a big Futbol match, they get down and party! I barely slept a wink last night, as FC Barcelona won the League of Champions last night 2-1, overcoming Arsenal with a great comeback from 0-1. Actually, I wasn't really watching the match, if you know what I mean, but it was a fun night, anyway. The streets were full of youngsters in their teens and twenties wandering around in packs - beers in hand, all waving their team flags and chanting or singing the team's songs. It was amazing. I didn't know any of the songs, so I basically stayed out of the way and watched as the night unfolded. Cars constantly honked their horns until 3AM (taxi's, too!), and most of the night was filled with explosions from fireworks. Not little firecrackers, but big, booming sounds that made me think of carbombs. Wild.

Good night to live in the city of the European Champions - next up? World Cup!!

Speaking of next up, I think tomorrow/today is going to be another fantastic day. I chose BCN because I knew it was a motorcycling city, and the Gran Semana de la Moto is just getting started! What's this? I had heard about this bike show a couple months ago, but reading motogp.com reminded me that this was going on, right now! You can read more about the show at motobcn.com

I can't believe all the stuff that's going to be happenning around me in the next few weeks, so hold on, cause it's going to get a little crazy! After the bike show, I have a special dinner planned with some friends from out of town, and then it's off to see if the weather reports are going to be correct about France. I'm not sure what to pack, because it could be wet, could be dry, but it's definitely going to be raining motorcycles!

Yee-Haa! (dammit, somebody hire me soon, because all this fun is getting addicting - and expensive!)

As a side note, I'm going to completely strip my laptop of everything extraneous, because the Gig's of photos are going to add up! Who's a MAC genius who can guide me through some important back-up protocols, because I've been having problems with iPhoto for a couple months?
 
just my .02, but it sure seesm like MotoGP bikes are finally moving towards F1 car racing with technology that makes piloting the machine easier, maybe too easy.......how else can you explain Stoner and Pedrosa going sooooo fast right away?!!?

the learning curve seems to have disappeared..........is Pedrosa really that good?......better than Rossi?
 
Hey Liam,

I'm not a BARFer, but I found this thread trough Google. I'm the admin over at the Toledo Sportbike Rider boards. http://www.tsbr.us/forums. My girlfriend lives in Barcelona and I am going to see her from Friday May 19th through the 29th and was hoping to get some information from you about the local bike scene. Check your PMs and/or email and let me know if you are open to talking with me. I've got a phone card that is 2 cents per minute to Spain, so it's easy for me to call!!

My gf said they were crazy in the streets last night also! Man do they love their futbol over there! LOL

Look me up man!

Moby
matt dot mcginnis at mcgintech.com
 
No trying to steal your thunder, but here's a few more pics of....

Strange bike:

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Barcelona:

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Monserrat:

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Barcelona:

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"The Brave Coast"

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If you haven't been to Costa Brava, you HAVE TO GO!!
 
Kinda disappointed with Arsenal's perfomance last night. And the ref's blew that game big time (Lehman shouldn't have been red carded and the Barca goal that resulted should have counted keeping the sides even). I won't rant anymore about this game because a) it's moot, and b) it's upsetting me (again):(

Anyway, good point, Liam that the Repsol boys could maintain such a fast pace and therefore the tires should be able to last even when pushed really, really hard. But, the Hondas aren't exhibiting the chatter that the Yamahas are experiencing. I didn't know that Michelin increased the width of their fronts. It was probably to appease Honda because of their problems last year. The oscillations could overwhelm the tire and cause it to fail faster than if everything was sorted. We'll see what's in store this weekend at Le Mans. MotoGP's finally returned to Europe and teams are getting new kit.

I'm not the biggest fan of traction control but where do you draw the line? I think it's making the sport easier. I loved seeing riders backing the bike into corners (a la Nicky) and going sideways on the exit.
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I hope MotoGP doesn't become like F1 where the cars matter more than driver. I watch MotoGP rather than F1 for the passing and tight racing. F1 is more about pit strategy. That's it.

Teams in the AMA do have some sort of traction control-the fuel curves. They can easily tune the engine to a specific track by detuning the engine in a particular gear to reduce tire spin. Or vice versa.

Also, I wouldn't consider myself a Mac genius but I know my way around one. PM me your questions and I'll see what I can do to help.
 
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