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Posted
  On 6/20/2023 at 2:24 PM, p6x said:

To piggy back on what @GuzziMoto said, I propose two excellent articles written by Mat Oxley for Motorsport magazine;

It is mainly a crankshaft length difference. V4 has more torque, Inline handles better up to a certain point. As we have witnessed this year, the M1 got more power, however lost its cornering speed.

https://www.motorsportmagazine.com/articles/motorcycles/motogp/why-are-motogp-v4s-faster-than-inline-4s/

In this second article, the same Mat Oxley explains in technical details why the Inline 4 handle better than the V4 engines. He also uses the example of how Zarco and Lorenzo faced a major set back when moving from the M1 to KTM and Ducati. While Zarco never recovered with KTM, Lorenzo made peace with his Ducati eventually.

https://www.motorsportmagazine.com/articles/motorcycles/motogp/why-inline-four-motogp-bikes-handle-better-than-v4-motogp-bikes/

Even myself now understand what the advantages and disadvantages of each architecture are.

What I found interesting, is that the advantages of the Inline can transform into cons. This is perfectly illustrated this year with both Fabio and Franco. The M1 has more power, but has lost its curving domination. Also the power they got is not enough for them to have the wings they need to compete with the Vs.

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I can get the crankshaft being shorter and stiffer for a V4.  Not sure why torque and power are affected.   I'm not sure if any or all engines use counter balancers.  The big-bang firing intervals are all unique to each manufacturer, both KTM and Ducati modeling it after their twins and Honda and Aprilia from their V4.  At one time Honda ran a V5 before the rule change. 

IIRC the Duc uses desmo valve train whereas all the other bike have pneumatic valve springs.  

Thanks for posting those references, I'll have to look at them.

Posted
  On 6/20/2023 at 2:55 PM, LowRyter said:

I can get the crankshaft being shorter and stiffer for a V4.  Not sure why torque and power are affected.   I'm not sure if any or all engines use counter balancers.  The big-bang firing intervals are all unique to each manufacturer, both KTM and Ducati modeling it after their twins and Honda and Aprilia from their V4.  At one time Honda ran a V5 before the rule change. 

IIRC the Duc uses desmo valve train whereas all the other bike have pneumatic valve springs.  

Thanks for posting those references, I'll have to look at them.

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The power difference is mainly in the better intake and exhaust that a V4 allows. There are also smaller differences like fewer bearings required that reduce friction. The firing interval isn't really part of it (they manipulate that anyway with the crank offset). But the natural balance of a V4 likely does play a minor part. It would make vibrations and harmonics easier to control. An inline 4 is by nature vibration prone.

The intake tract and exhaust for an inline 4 layout and how it fits into the chassis makes it harder to get the same power you can get out of a V4. The V4 allows for a better downdraft shot to the intake valves. The exhaust layout is also cleaner. It is not just the motor, but how the motor fits in the chassis. The inline 4 layout means the intake system has to work around the chassis and thus is compromised. minor differences add up.

Desmo is nice, it does allow more abrupt opening and closing of the valves. But that is only part of the picture. Sure, the Ducati tends to make the most power. But the KTM and Aprilia are right there with it, along with the Honda. The Yamaha, and the Suzuki when they were in it, just doesn't make the kind of power the others do. They have improved the Yamaha's power, but not enough. And much of what they did gain only highlighted other issues. The Yamaha also seems to be lacking in traction control strategy, as well as aero. More power helps, but they are struggling to use the power. Yamaha did not hire Magneti Marelli techs the way the others did. And while traction control tech is spec and limited, because of that it makes it even more important to get the most out of what you have. Yamaha resisted, they thought they could make the new spec system work using the same people that made their bespoke system work. The European teams hired MM techs.

Posted
  On 6/20/2023 at 3:42 PM, GuzziMoto said:

The power difference is mainly in the better intake and exhaust that a V4 allows. There are also smaller differences like fewer bearings required that reduce friction. The firing interval isn't really part of it (they manipulate that anyway with the crank offset). But the natural balance of a V4 likely does play a minor part. It would make vibrations and harmonics easier to control. An inline 4 is by nature vibration prone.

The intake tract and exhaust for an inline 4 layout and how it fits into the chassis makes it harder to get the same power you can get out of a V4. The V4 allows for a better downdraft shot to the intake valves. The exhaust layout is also cleaner. It is not just the motor, but how the motor fits in the chassis. The inline 4 layout means the intake system has to work around the chassis and thus is compromised. minor differences add up.

Desmo is nice, it does allow more abrupt opening and closing of the valves. But that is only part of the picture. Sure, the Ducati tends to make the most power. But the KTM and Aprilia are right there with it, along with the Honda. The Yamaha, and the Suzuki when they were in it, just doesn't make the kind of power the others do. They have improved the Yamaha's power, but not enough. And much of what they did gain only highlighted other issues. The Yamaha also seems to be lacking in traction control strategy, as well as aero. More power helps, but they are struggling to use the power. Yamaha did not hire Magneti Marelli techs the way the others did. And while traction control tech is spec and limited, because of that it makes it even more important to get the most out of what you have. Yamaha resisted, they thought they could make the new spec system work using the same people that made their bespoke system work. The European teams hired MM techs.

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I don't get how a V engine has better combustion flow than a straight inline engine.  If anything the inline layout should allow for more room to place the intake exhaust manifolds.   Not so certain the vibrations given than all those engines are big bang either.  Not disputing as much as just don't understand.  So far a bearings, I'd guess the V engine have fewer but larger bearings?  maybe not.

One area the European bikes might have an advantage is with the Magneti Marelli ecu.  Since they aren't a supplier to the Japanese bikes.  I'd still be interest to know advantages with desmo vs pneumatic valve train.  

Posted
  On 6/20/2023 at 8:33 PM, LowRyter said:

I don't get how a V engine has better combustion flow than a straight inline engine.  If anything the inline layout should allow for more room to place the intake exhaust manifolds.   Not so certain the vibrations given than all those engines are big bang either.  Not disputing as much as just don't understand.  So far a bearings, I'd guess the V engine have fewer but larger bearings?  maybe not.

One area the European bikes might have an advantage is with the Magneti Marelli ecu.  Since they aren't a supplier to the Japanese bikes.  I'd still be interest to know advantages with desmo vs pneumatic valve train.  

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A V4 engine typically uses three main bearings, while an inline 4 requires five.

You typically want exhaust pipes to be equal length, and as straight as possible, the same for intake tracts. It is easier to achieve that on a V4. An inline 4 is much wider and it becomes difficult to make all four equal and straight. Plus you have the chassis getting in the way with an inline 4, where as with a V4 the chassis is much less in the way.

With the MM ECU and traction control, the other guys literally hired engineers from MM, where as Yamaha thought their guys could figure it out. The old "how hard could it be" hubris.

Read the articles at the links posted, that is a good starter

Posted

Practice 1 of the Assen MotoGP, Marc Marquez 21st out of 23 riders.

1.865 seconds of Marco Bezzecchi 1st during this session.

I don't think I can remember a run with Marquez being that low in the classification. I am not certain he attempted to set a time though, which would be unlike him anyway.

 

 

Posted
  On 6/23/2023 at 10:38 AM, p6x said:

Practice 1 of the Assen MotoGP, Marc Marquez 21st out of 23 riders.

1.865 seconds of Marco Bezzecchi 1st during this session.

I don't think I can remember a run with Marquez being that low in the classification. I am not certain he attempted to set a time though, which would be unlike him anyway.

 

 

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He apparently did fit a fresh soft tire at the end, but that was all he had. That said, he should take it slow and easy, working up to a pace instead of what he has been doing. Good for him. No points for "winning" first practice.

Nakagami in 7th, so the speed in there in the Honda. If Nakagami can pull off 7th, someone of Marcs ability should be able to put it top three, or at least top five. But he can't do that if he bins it going for more speed than he is ready for.

Posted

I'm still pulling for BB33, and did terrific this weekend, but damn, two days in a row, docked a position. Great race!

Posted
  On 6/26/2023 at 2:53 PM, LaGrasta said:

I'm still pulling for BB33, and did terrific this weekend, but damn, two days in a row, docked a position. Great race!

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Marquez pulled out of the race. That's 2 in a row...

  • Like 1
Posted

It was great to see Binder up there, and it sucked that he made the same mistake twice. But still a good finish for him. It was strange to see Martin right behind binder make the same mistake, maybe slightly more so, and not cop a penalty. I think that came down to Martin not already having a strike against him from earlier in the race. 

Marc looks to be in deep trouble. He seems spooked, like the way JLo was after a while on the Honda. Once the fear sets in, it is hard to shake. Many can't. Marc can't seem to get away with the mistakes he used to get away with. Curious to see if he can overcome the fear and get his confidence back.

Also bummed for Miller. I would love to see him do better. But great ride from Aleix.

  • Like 1
Posted
  On 6/26/2023 at 7:11 PM, GuzziMoto said:

It was great to see Binder up there, and it sucked that he made the same mistake twice. But still a good finish for him. It was strange to see Martin right behind binder make the same mistake, maybe slightly more so, and not cop a penalty. I think that came down to Martin not already having a strike against him from earlier in the race. 

Marc looks to be in deep trouble. He seems spooked, like the way JLo was after a while on the Honda. Once the fear sets in, it is hard to shake. Many can't. Marc can't seem to get away with the mistakes he used to get away with. Curious to see if he can overcome the fear and get his confidence back.

Also bummed for Miller. I would love to see him do better. But great ride from Aleix.

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Turns out whether or not you get a penalty for exceeding track limits like Binder did depends on how close the guy behind you is, or if you make a pass on the guy in front of you (so they say). Martin did not get a penalty because no one was behind him, and he did not use the extra speed gained to make a pass on Aleix. In fact, he didn't try a last lap pass (he says) because he knew he ran on the green and knew they would take the spot back. Meanwhile, Aleix says he saw Binder run onto the green and figured they would give him the spot over Binder. So no reason to risk it.

  • Like 1
Posted
  On 6/27/2023 at 12:43 PM, GuzziMoto said:

Aleix says he saw Binder run onto the green and figured they would give him the spot over Binder. So no reason to risk it.

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I watched a debrief of the GP, and this point was actually looked down as negative; spoiling the spectacle because Aleix did not attempt the pass.

The presenter reminded us that some of the most spectacular passes infringed rules that have newly been enacted. There have been so many of these last curve passes that remain in memory that we don't want them to go away.

One example was Rossi's overtaking on Stoner at Laguna Seca.

I feel the same. The races should happen on tracks, and not be decided by people watching it on monitors and deciding afterwards if a move is legal or not.

  • Like 1
Posted

I agree. I don't like where they have gone with "track limits". I think it is simple, if you don't want racers using part of the track, don't pave it. If you don't want them exceeding the track limits stop paving beyond track limits. Leave it grass. Maybe pave areas say 5 or 10 feet away from the track, with grass between the track and that paved area, to give racers a chance to regain control if they run off. But if a racer is exceeding track limits and if it is grass right beyond track limits they will and should run the risk of crashing unless they pick up the bike and let off the gas. Paving right up to the edge of the track is only encouraging racers to exceed track limits and not back off.

If you don't want racers to use that part of the track stop paving it. Racing should be done on track. Not in the stewards room.

  • Like 1
Posted

Racing w/o rules...sounds like a recipe for disaster....oh wait...we already have that!  We have rules and lots of crashes already as the riders go right up to the edge, and over all of the time.

I think for safety reasons, creating a non paved area would lead to more injuries....not great.

But at the end of the day...Marquez does seem to be finished...the accumulation both physical and mental of the injuries along with what appears to be an even more reckless style of riding is taking its toll on him and other riders.  He probably thinks he has a few more seasons in him, but the results don't suggest it...a bit like Tiger Woods...may win from time to time but not nearly as consistently as in the past.

  • Like 1
Posted

For the longest time the area next to tracks wasn't paved. There were not high numbers of injuries due to that fact. Heck, I used to race pretty seriously and never crashed because the pavement didn't extend past the edge of the track. I did crash periodically, but never because of the grass next to the track.

That said, plenty of racers have pointed out that paving the area next to the track only encourages racers to take bigger risks as it becomes easier to get away with it if you over do it.

No one is suggesting racing without rules. But paving next to the track and then making a rule saying racers aren't allowed to use that pavement is stupid. If you don't pave it you would not need the rule.

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  • Thanks 1
Posted
  On 6/28/2023 at 5:04 PM, PJPR01 said:

But at the end of the day...Marquez does seem to be finished...the accumulation both physical and mental of the injuries along with what appears to be an even more reckless style of riding is taking its toll on him and other riders.  He probably thinks he has a few more seasons in him, but the results don't suggest it...a bit like Tiger Woods...may win from time to time but not nearly as consistently as in the past.

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I am tempted to agree to that reasoning; however Marc Marquez has shown that he still has it in him, his talent seems to be intact.

Unfortunately, he no longer has the media to express it. As he tries to exceed the limits of his RCV, there is no longer any forgiveness. Not that there was any before, but you cannot go down 5 times in the same week-end and expect to come out unscathed.

He still is the number one figure of the GP now that VR46 is no longer there. I believe people watch to see what he will do rather than the Ducati show that is taking place at every single race, short or long.

Has he become "desperate"? watching him certainly seems to indicate it.

He is going to be able to recover from his latest injuries during the summer break, with little hope that Honda will have found a solution to improve the bike.

I sure hope we are not going to continue too long with a single brand preempting each race.

  • Like 2

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