Pecco Moto GP

[GuzziMoto]

Several aspects of the Indonesian round stand out.

The biggest one being the rain, which really mixed things up. Rain always mixes things up, but here we had dry running until the race, even the morning warm up was run in the dry. So it was a learning experience for the racers to figure out how fast they could go in the rain.

But also, Michelin brought an old tire construction with a stiffer carcass and that really made a difference. It put Fabio back at the front and it put the Honda's (Marc and Pol) at the back. It seems the new Honda did not like that tire at all, after being fast in the test earlier with the current tire. I really think that is messed up. Honda (who I am not really a fan of) put all that effort into building a bike that works with the new tire and they switch to an old design tire for the race, after having them test the new design tire at the track a few weeks ago. It also highlights the flaw with the spec tire. While in theory everyone using the same tire means the tire aspect is equal, but clearly it is not. The Yamaha doesn't work nearly as well on the new tire spec as it does on the old spec tire. The same with the Ducati. While the Honda doesn't work nearly as well on the old spec tire as it does on the new spec tire. But it seems there is nothing in place to prevent Michelin from bringing whatever spec tire they want to a race weekend. And what spec tire they bring plays a huge part in determining who is fast and who is slow. If they are going to make everyone use Michelin tires, the teams should at least get to choose which Michelin tires they want to use and not be at the mercy of Michelin.

[p6x]

@GuzziMoto why should there be rules in place to prevent the tire provider to take measures for safety purposes? the reason why Michelin thought right to bring back a four years old construction tire was justified because of the expected high temperatures. While I understand the argument from Pol Espargaro, Michelin's intention was certainly not to disadvantage anyone. 

If there was any doubt, the Indonesian outing confirmed how tire dependent are today's MotoGP bikes.

Do you remember the F1 Indianapolis 2005 Michelin tire failure? I think this was a catastrophe they are not prepared to have repeated again, with major consequences for motorcycle pilots.

Is it the correct reaction to be disappointed? should the blame be squarely put on Michelin? should Michelin have designed MotoGP 2022 tires taking into account the Indonesian high temperatures? did they factor them in? did they not have enough time to incorporate the high temperature possibility in the design? did they chose to ignore it? I don't have any answer for that. 

Yes, it is disappointing that this tire swap affected negatively Honda in particular, who had designed today's bike with the expected 2022 Michelin Tires. That other teams had too is not a soothing factor either.

Should have the teams left sole judges of which tire type to run in Mandalika? should have Dorna taken the decision based on whatever Michelin presented in terms of technical facts? Should the pilots have decided? I think Michelin's decision to not take any risk was probably the most legitimate one. It is just terrible those who were so obviously disadvantaged could not get some kind of specific assistance to compensate, but other teams may have objected to that.

I don't think there was anything better that could have been done.

I am compassionate of what happened to Marc Marquez, most likely because he refused to admit that he was going to be impaired by the tires. Sometimes being a great champion implies stoicism in the face of adversity. Others such as Mike Doohan following his accident, accepted that he would never be able to pilot his bike efficiently to win, and consequently retired.

[GuzziMoto]

1 hour ago, p6x said:

@GuzziMoto why should there be rules in place to prevent the tire provider to take measures for safety purposes? the reason why Michelin thought right to bring back a four years old construction tire was justified because of the expected high temperatures. While I understand the argument from Pol Espargaro, Michelin's intention was certainly not to disadvantage anyone. 

If there was any doubt, the Indonesian outing confirmed how tire dependent are today's MotoGP bikes.

Do you remember the F1 Indianapolis 2005 Michelin tire failure? I think this was a catastrophe they are not prepared to have repeated again, with major consequences for motorcycle pilots.

Is it the correct reaction to be disappointed? should the blame be squarely put on Michelin? should Michelin have designed MotoGP 2022 tires taking into account the Indonesian high temperatures? did they factor them in? did they not have enough time to incorporate the high temperature possibility in the design? did they chose to ignore it? I don't have any answer for that. 

Yes, it is disappointing that this tire swap affected negatively Honda in particular, who had designed today's bike with the expected 2022 Michelin Tires. That other teams had too is not a soothing factor either.

Should have the teams left sole judges of which tire type to run in Mandalika? should have Dorna taken the decision based on whatever Michelin presented in terms of technical facts? Should the pilots have decided? I think Michelin's decision to not take any risk was probably the most legitimate one. It is just terrible those who were so obviously disadvantaged could not get some kind of specific assistance to compensate, but other teams may have objected that too.

I don't think there was anything better that could have been done.

I am compassionate of what happened to Marc Marquez, most likely because he refused to admit that he was going to be impaired by the tires. Sometimes being a great champion implies stoicism in the face of adversity. Others such as Mike Doohan following his accident, accepted that he would never be able to pilot his bike efficiently to win, and consequently retired.

No one is saying that Michelin can't take measures for safety. But first, there were no tire failures in testing, so there really was no evidence for needing to take measures for safety. Secondly, if Michelin did feel they needed to bring more durable tires they should have chosen more durable tires from this years tire range. Not brought out a tire they haven't used in years. And if they were bringing out a tire that wasn't in the current range of tires offered, they should have either brought that tire to the test or made running that tire optional. Instead they brought out a tire that made some guys faster and other guys slower. It also ended up putting Marc Marquez in a scary wreck. So, maybe not a decision that improved safety. At least some racers weren't safer due to the choice made.

The F1 tire fiasco was in part due to the restrictive rules that F1 had in place at the time, not allowing Michelin to bring in tires that would have worked. In F1 back then each manufacturer had to pick the tires they were bringing in advance and they weren't allowed to use any other tires. It was an attempt to handicap Michelin, as Michelin were capable of bringing in tires over the course of the weekend if required.

Spec tires are not 100% bad, but there are clear disadvantages to a spec tire. Spec tires have their place, in lower series where it is more an entry class and you are just trying to level the playing field and keep costs down. But at the top level of racing spec tires are stupid. They don't keep costs down and they don't level the playing field. And this past weekends race showed that.

[LowRyter]

It's always spectacular to see these guys race in the rain.   Olivera and Fabio were absolutely laying it down.  The lean angles were amazing and the lap times were fast.  There was close racing on the pack.  I'd say the tires held up fine.

I think the big takeaway is whether MM93 needs to retire.  He's just been beat to a pulp and I have to wonder about his long term health.  

There are lots of fresh young riders many as aggressive as MM or more so.  I don't even know most of them.  It's interesting watching different teams and riders go to the top and then to the bottom of pole.

[Lucky Phil]

On 3/20/2022 at 2:04 PM, p6x said:

Incredible number of crashes from MM93 in Indonesia, including one of the most spectacular high side during the warm up....

 

Something a bit weird about this crash. Did anyone else notice the front forks dip about 20mm and then recover just before he turned it in? Look at the side on replay if you still can. At first I thought he had applied a bit of front brake to load the front tyre before entry but the forks reaction was a bit too aggressive for that. Then my mind turned to a mechanical issue like it's lost a brake pad or something and caused a momentary hick up to the front end just before he turned it in. Interesting and once you've seen it side on you can notice it from the bike view as well. I'd love to get a look at the data just before the crash.

https://www.motogp.com/en/news/2022/03/21/marc-marquez-on-one-of-the-biggest-crashes-he-s-had/411741

Ciao  

[Lucky Phil]

6 hours ago, GuzziMoto said:

No one is saying that Michelin can't take measures for safety. But first, there were no tire failures in testing, so there really was no evidence for needing to take measures for safety. Secondly, if Michelin did feel they needed to bring more durable tires they should have chosen more durable tires from this years tire range. Not brought out a tire they haven't used in years. And if they were bringing out a tire that wasn't in the current range of tires offered, they should have either brought that tire to the test or made running that tire optional. Instead they brought out a tire that made some guys faster and other guys slower. It also ended up putting Marc Marquez in a scary wreck. So, maybe not a decision that improved safety. At least some racers weren't safer due to the choice made.

The F1 tire fiasco was in part due to the restrictive rules that F1 had in place at the time, not allowing Michelin to bring in tires that would have worked. In F1 back then each manufacturer had to pick the tires they were bringing in advance and they weren't allowed to use any other tires. It was an attempt to handicap Michelin, as Michelin were capable of bringing in tires over the course of the weekend if required.

Spec tires are not 100% bad, but there are clear disadvantages to a spec tire. Spec tires have their place, in lower series where it is more an entry class and you are just trying to level the playing field and keep costs down. But at the top level of racing spec tires are stupid. They don't keep costs down and they don't level the playing field. And this past weekends race showed that.

There's nothing new here, new tyre constructions favour different bikes and riders. Stoner had the same issue in 2011 or 12 when Bridgestone released a new front carcase during the season and it was a disaster for the Honda and him on corner entry. Same in later years also a few times. The spec tyre is costly for the bike manufacturers as they need to revamp frames and swingarms to suit changes in tyres. You can vary tyre construction at the drop of a hat for pretty much zero additional costs but if they release a new construction that doesn't work with your bike then it's a frame/swingarm redesign and construction. The reality is these days that racing is now all about the "show" and money so Dorna dont care about fairness really. The more unpredictable it is the better for them if it makes the "show" more interesting and exciting. I'm more "the sport is primarily about the competitors and the spectators are secondary to that" If someone or some manufacturer dominates then that probably because they deserve to and the others need to step up. Do I want the Mick Doohan show again, No but the racings a bit of a lottery these days where the rider simply can't dig deep and make up for a less than perfect bike setting or tyre choice or poor starting position from a bad practice or qualifying. Add to that most of the races are a tyre conservation strategy with everyone riding around for 2/3rds race distance nursing tyres waiting for the last 1/3 for when the real racing begins. The more it evolves the closer it's getting to F1 which is to me the most boring motorsport around.

Ciao 

[motortouring]

19 hours ago, Lucky Phil said:

Something a bit weird about this crash. Did anyone else notice the front forks dip about 20mm and then recover just before he turned it in? Look at the side on replay if you still can. At first I thought he had applied a bit of front brake to load the front tyre before entry but the forks reaction was a bit too aggressive for that. Then my mind turned to a mechanical issue like it's lost a brake pad or something and caused a momentary hick up to the front end just before he turned it in. Interesting and once you've seen it side on you can notice it from the bike view as well. I'd love to get a look at the data just before the crash.

https://www.motogp.com/en/news/2022/03/21/marc-marquez-on-one-of-the-biggest-crashes-he-s-had/411741

Ciao  

As a vehicle dynamics engineer, I must say I did not really see what you did. But, when loosing grip sideways and releasing the brake to find grip again, that is exactly what would happen before the high-sider. He must have found grip on the front end.

[p6x]

@GuzziMoto

I was trying to get some information on what exactly determined Michelin's decision to bring a 2018 tire with a different casing.

I combed the French MotoGP reviews of the GP, and according to Michel Turco, the decision was taken following the pre-season tests conducted a month ago.

The average asphalt temperature of 60 degC translated to 160 degC on the tires during load. Michelin determined the tires would not last for the duration of the race, and consequently shipped an older tire equipped with a casing that diminished the temperature load of 20 to 30 degC. 

This is the only technical explanation I got. I imagine that Michelin informed all the interested parties of that decision. That 2018 tire did not work well on the Honda, while it appeared to perform better on other machines. In any case, because of the rain, the track temperature was at 25 degC. 

[Lucky Phil]

2 hours ago, p6x said:

@GuzziMoto

I was trying to get some information on what exactly determined Michelin's decision to bring a 2018 tire with a different casing.

I combed the French MotoGP reviews of the GP, and according to Michel Turco, the decision was taken following the pre-season tests conducted a month ago.

The average asphalt temperature of 60 degC translated to 160 degC on the tires during load. Michelin determined the tires would not last for the duration of the race, and consequently shipped an older tire equipped with a casing that diminished the temperature load of 20 to 30 degC. 

This is the only technical explanation I got. I imagine that Michelin informed all the interested parties of that decision. That 2018 tire did not work well on the Honda, while it appeared to perform better on other machines. In any case, because of the rain, the track temperature was at 25 degC. 

Yes the used the old rear to cope with the expected high track temps.

Ciao

[Lucky Phil]

4 hours ago, motortouring said:

As a vehicle dynamics engineer, I must say I did not really see what you did. But, when loosing grip sideways and releasing the brake to find grip again, that is exactly what would happen before the high-sider. He must have found grip on the front end.

Carefully watch the front forks just before he tips into the corner, maybe 50m before and you'll see them compress sharply and rebound which isn't normally what you'd expect at that point as it upsets the bike just before entry.

The highside mechanism is a pretty straight forward one. The rear tyre loses grip and begins to slide which tightens the line of the bike to varying degrees and the rear suspension extends once again to a varying degree. The rider or the traction control then backs the power off and the tyre grips again, the rear suspension compresses and depending on the degree of the above mentioned dynamics plus the speed the lean angle and quite a few other factors the resultant potential energy created is released in one violent event for the bike and rider. The rest is the dissipation of that now kinetic energy into altitude for rider and bike and friction when they hit the ground.  

Modern traction control systems are supposed to mitigate the event well before the attitude of the bike is allowed to create the potential energy however there isn't currently any protection for an "off throttle" highside Marquez experienced. 

Ciao 

[FreyZI]

I'll come out and say that I'm not a big MM93 fan.  He could use a dressing down like Ice-Man gave Maverick.

Some arrogance is undoubtedly necessary to do what GP riders do, and deserved for MM, but some of his stunts (both en race and after) have been utterly stupid.  Remember that idiotic arcade game stunt after winning the championship in 2018?  

I do give MM credit for taking massive bodily injury and getting back in the saddle and piloting a bike again and again.  BBB.    Time to retire, or do the VR46 thing?  My guess is as long as he can command $20 million dollars a year in contract and endorsements, he'll stick around until his body quits.  Unlikely that Honda will quit him.

Anywho ...

The crash in the Indonesia warm up was spectacular.

Now, let me understand the dynamics of a high side:

I found this definition of "highsider" on Wikipedia:

Technical explanation[edit]

Forces occurring between the motorcycle and the road (such as those that result in accelerating, decelerating and turning) occur at the contact patch through friction and normal forces. There is a limited amount of force tangential to the road that the contact patch can transmit before the tire begins to lose traction, and therefore slide or skid.

When going through a curve on a motorcycle, centripetal force (added to the other lateral forces such as acceleration or deceleration) is transferred from the road to the motorcycle through the contact patch, and is directed at a right angle to the path of travel. If the net force is greater than the static friction coefficient of the tire multiplied by the normal force of the motorcycle through the tire, the tire will skid outwards from the direction of the curve.

Once a tire slips in a curve, it will move outwards under the motorcycle. What happens from there depends on how well the rider is able to restore balance and control. If the tire regains traction after the rider starts to skid while the motorcycle is moving sideways, the tire will stop its sideways movement causing the motorcycle to suddenly jerk into an upright position (and beyond). This movement can easily cause the rider to be thrown off.

[end quote]

This makes some sense to my addled brain.  Basically, a high side starts off like a low side.  Then, either: 1) the bike tips further toward the ground, the tire patch evaporates, and the bike skids wheels forward-ish, 2) the lucky rider recovers just enough friction in the tire patch to return to equilibrium, or 3) the tire patch grabs and -- because the axis of the bike has turned too far relative to the direction of travel -- it acts like a fulcrum, turning the bike into a lever and the rider into the payload.

In option (2) or (3), it seems that at the moment the tire patch grabs, the rear shock would be loaded.  Then, it's a combination of the release of that load and the force (tangential?) from the rotation of the bike (upward/toward the outside of the curve) about the longitudinal axis that can either buck the rider out of the seat or cast the rider into the sky, a la Marquez.

CMIIW.

Assuming there's some reason to the above, what are the relative contributions of the unloading of the shock and the rotation of the bike?  How would one modify their shock settings to allow high performance without setting the stage for a high side on accelleration?

Cheers,

Frey

 

 

[Lucky Phil]

12 minutes ago, FreyZI said:

I'll come out and say that I'm not a big MM93 fan.  He could use a dressing down like Ice-Man gave Maverick.

Some arrogance is undoubtedly necessary to do what GP riders do, and deserved for MM, but some of his stunts (both en race and after) have been utterly stupid.  Remember that idiotic arcade game stunt after winning the championship in 2018?  

I do give MM credit for taking massive bodily injury and getting back in the saddle and piloting a bike again and again.  BBB.    Time to retire, or do the VR46 thing?  My guess is as long as he can command $20 million dollars a year in contract and endorsements, he'll stick around until his body quits.  Unlikely that Honda will quit him.

Anywho ...

The crash in the Indonesia warm up was spectacular.

Now, let me understand the dynamics of a high side:

I found this definition of "highsider" on Wikipedia:

Technical explanation[edit]

Forces occurring between the motorcycle and the road (such as those that result in accelerating, decelerating and turning) occur at the contact patch through friction and normal forces. There is a limited amount of force tangential to the road that the contact patch can transmit before the tire begins to lose traction, and therefore slide or skid.

When going through a curve on a motorcycle, centripetal force (added to the other lateral forces such as acceleration or deceleration) is transferred from the road to the motorcycle through the contact patch, and is directed at a right angle to the path of travel. If the net force is greater than the static friction coefficient of the tire multiplied by the normal force of the motorcycle through the tire, the tire will skid outwards from the direction of the curve.

Once a tire slips in a curve, it will move outwards under the motorcycle. What happens from there depends on how well the rider is able to restore balance and control. If the tire regains traction after the rider starts to skid while the motorcycle is moving sideways, the tire will stop its sideways movement causing the motorcycle to suddenly jerk into an upright position (and beyond). This movement can easily cause the rider to be thrown off.

[end quote]

This makes some sense to my addled brain.  Basically, a high side starts off like a low side.  Then, either: 1) the bike tips further toward the ground, the tire patch evaporates, and the bike skids wheels forward-ish, 2) the lucky rider recovers just enough friction in the tire patch to return to equilibrium, or 3) the tire patch grabs and -- because the axis of the bike has turned too far relative to the direction of travel -- it acts like a fulcrum, turning the bike into a lever and the rider into the payload.

In option (2) or (3), it seems that at the moment the tire patch grabs, the rear shock would be loaded.  Then, it's a combination of the release of that load and the force (tangential?) from the rotation of the bike (upward/toward the outside of the curve) about the longitudinal axis that can either buck the rider out of the seat or cast the rider into the sky, a la Marquez.

CMIIW.

Assuming there's some reason to the above, what are the relative contributions of the unloading of the shock and the rotation of the bike?  How would one modify their shock settings to allow high performance without setting the stage for a high side on accelleration?

Cheers,

Frey

 

 

The rear shock action just adds to the force of a high side, even with  ridged rear suspension a high side would still happen. The only way to control one is to back out of the throttle well before it gets away on you or use the throttle to keep the slide going and either let it lowside OR use power to maintain the slide and ride it out so to speak. Thats a High side ON the gas. MM suffered the more difficult to deal with OFF throttle high side and the only way out of that is to get hard on the gas and ride it out which in the real world would be pretty much impossible. Once it lets go in that scenario you don't have the reaction necessary to get on the throttle and modulate it to ride it out and save it. See how speedway riders ride and what happens the moment they shut the throttle. The bike either straightens up and heads for the fence or high sides them. The process is the same. It's the mental barrier you need to cross to be a speedway rider. The more you're running wide and the fence is coming at you fast the bigger handful of throttle you need to correct the situation.

Ciao   

[GuzziMoto]

I am also not exactly a fan of Marc Marquez. I respect his talent, but I don't like the way he rides with no regard to others on the track with him. Over the years he has put more other racers on the ground by hitting them then most others have. Contact does happen, sometimes it is unavoidable. But for Marc he seems to make no effort to avoid contact with others.

That said, it seems his crashes have caught up with him. He does crash a lot, and has managed to stick around longer than most others who ride like that (think Wayne Gardner). If he doesn't walk away soon he may end up in even worse shape. But since he has outright said he won't keep racing if he can't win I expect he will walk away soon. At this point he isn't even the fastest guy on a Honda.

Oh, and my fastest crash was at Roebling Road in turn 9 running around 130 mph. It was brutal, destroyed the bike (ripped the forks in half) and dislocated my shoulder (among other injuries).

[KINDOY2]

During the journey back to Spain, Marc Marquez began to experience discomfort with his vision and upon his arrival in Barcelona on Monday, he had an emergency visit to the Hospital Clinic de Barcelona with his trusted ophthalmologist, Dr. Sanchez Dalmau, who after an examination confirmed a relapse in the diplopia that the rider suffered last November.

[Joe]

Valentino Rossi wearing flip flops.......