Jerez MotoGP Monday Test Round Up: Quartararo Leads, Honda Use New Chassis, Yamaha Make Small Steps

The day after the Spanish round of MotoGP, the riders were back on track, busting out lap after lap with a lot of work to be done. After 25 laps on Sunday in the punishing heat, almost the entire grid did another three race distances or more on the Monday. Everyone rode, with the exception of Andrea Iannone, who was still suffering with an extremely painful ankle after a crash on Saturday, and Stefan Bradl, who had handed his test bike over to Marc Márquez to turn some laps on.

Conditions were ideal, the track all rubbered in after Sunday's race and the track temperature in the mid-40s, perfect for Jerez. That was both a good thing and a bad thing: riders who wanting to work on something specific, such as corner entry or mid-corner speed, could take full advantage of the grip to understand the finer details of what they were working. Teams and riders who are chasing traction on corner exit, like the factory Yamaha riders, or confidence in low grip conditions, like Jorge Lorenzo were not helped at all. With plenty of grip, it was much harder to work on their problems.

Fabio Quartararo ended the day as fastest, destroying his own pole record by half a second. And it wasn't just a single lap: of the 73 laps the Petronas SRT Yamaha rider put in, 21 were under the 1'38 barrier, 7 of them faster than 1'37.5. As a satellite rider, the Frenchman did not have a whole bunch of things to test, though he did have some forks from Ohlins to try.

There was nothing big, Quartararo said. "It is on the small details, so I tried a new front fork which was really good and some settings, new geometry on the bike, but we found some really good and positive points for the next few races." The Frenchman was very happy with his pace, and felt extremely confident going into his home race.

Confidence and rivalry

Having seen the stress a home race can put on a rider, with the example of Johann Zarco last year, the Petronas team will be shielding him from too much attention at Le Mans. "Now I am feeling really good for it. We made a really good weekend with pole position, fighting for the top places in the race. Today we managed to get more than the fastest lap along with the pace we had on the hard tire so we are working really good. I think I am arriving with top confidence and of course home MotoGP will be really good and the fans will give extra motivation. We know that it is a little bit more stressful but we will manage to be calm at my home GP."

Teammate Franco Morbidelli was third fastest, the Petronas Yamaha clearly quick, the Italian also focusing mainly on setup to improve his feeling with the bike. Morbidelli has a higher spec Yamaha M1 than Quartararo, though the differences are mainly that the Frenchman has 500 RPM less than Morbidelli, and is using older aluminum forks, rather than the factory-spec full carbon fiber Ohlins which the Italian is using.

Intra-team rivalries are fierce, however, even among two such laid-back characters as Quartararo and Morbidelli. When Morbidelli was told by a journalist that Quartararo had a different set of forks to test, the Italian's hackles were raised. Suspicion swept across his face, until we explained that it was just an upgrade on Quartararo's older-spec forks, not an update to factory-spec kit.

Sacrifices made

Cal Crutchlow was second fastest, but as a satellite rider, he too had little to test other than setting. Crutchlow is trying to find the feeling he had with his 2018 bike, the price of Honda's additional horsepower being a slightly different bike balance, which has sapped confidence in the front.

The problem, it seems, is a lot to do with the much larger volume airbox which feeds more oxygen into the more powerful engine. That has necessitated relocating a lot of parts which previously lived under the tank. The steering damper sits behind the headstock, and a lot of electronics have been shifted out to sit behind the nose of the fairing, along with some hidden under the cover on the left side of the frame. Moving all these parts about changes the bike balance, and getting that feeling back is a complex process.

The new air intake system makes switching back to the old chassis impossible. So one way the LCR Honda team have tried to get back some of the old feeling is by creating a sort of hybrid bike, as Cal Crutchlow described it.

"I still don't get the same feeling as the 2018 chassis, and we need to work on that," Crutchlow said. "But it's not going to come through setting. Unfortunately, we're not on the 2018 chassis as such, we're on something that fits more the 2019 engine, and the feeling is just a little bit different. I don't have the confidence in the front that I had last year, or that Taka has got in his bike. And in the middle of a lot of the fast corners here, Taka is faster than all the Honda riders, and that's because of the chassis he's on."

"I didn't use my full race bike," Crutchlow said. "I didn't use it on Friday either. That can be another thing we have to look at and work on, because we think that one area of the bike is pushing the front even more, where today, I felt a little bit better than that. But overall, the pace was good. I feel fast, I went way under my pole position time, which was 1'36.7, I wanted to take my pole record back, but Quartararo was faster, and that's it. He's also 12 years younger than me! But he's done a great job all weekend, and it's good to see, it's good to see these other guys in the mix. But like we said last night and sat in our meeting, there's 12 guys that can be stood on the podium, and I finished eighth yesterday."

Newer is better

The factory Honda team is looking for more permanent solutions. Marc Márquez took the test bike Stefan Bradl drew so much attention on during the Jerez weekend, which features an aluminum chassis with carbon fiber covers on. Other factories have used this technique to modify the stiffness of parts of the chassis without designing and building a brand new frame, and it looks like HRC are following down this path.

Márquez was positive in his remarks about the frame, playing the usual testing game of trying to camouflage the truth to keep it hidden from journalists, and thereby also rival factories. Márquez' comments would have scored very high points in any MotoGP drinking game – "Some positives, some negatives", "you gain some things, you lose some other things", "racing is a compromise", "we understand some things for the future". All great racing truths, none of them conveying any actual information.

The timesheets were a little more helpful in that regard. "I tried Bradl’s bike because it's a different bike and I just tried to understand that concept. I did two runs. It was positive and I did the best lap time with that bike," Márquez said. Looking at the run where Márquez did his fastest lap, he went out and did four flying laps, a 1'37.657, a 1'37.260, a 1'37.880, and a 1'37.681. Four fast laps, at consistent pace, which suggests the bike has some benefits to offer.


Márquez' pace was very strong during the test. He may not have gotten into the 1'36s, but he did 25 out of 75 laps in the 1'37s. Overall, Márquez looked to have the strongest pace in the test at Jerez. Other than testing Stefan Bradl's prototype bike, the reigning world champion concentrated on corner entry, and especially the engine braking issue which is pushing the front at times.

They made some more progress there on Monday. "On my current bike I was working a lot on corner entry. In that area of the engine brake, that is where we had more problems during the first three races. Here we, I said already in the press conference, that we improved a lot. But still they were some weak points, so we worked there. We found something that was interesting and then just another concept things for the future."

The added grip at Monday's test did not help Jorge Lorenzo work on his weakest point, the feeling with the bike when grip is low. Lorenzo tried another new tank configuration, in search of support under braking. Whether it helped or not is open to question: the Spaniard crashed at Turn 6 – the hardest braking point at the circuit – a point where he was struggling to get the bike stopped and turned in all weekend, as well as in the test.

His test ended after another big crash at Turn 7 at the end of the day. Though he was not seriously injured, the crash took the wind out of his sails, and knocked his confidence. Left feeling very sore, he went back to his hotel before we got a chance to speak to him about his day.

Baby steps

Maverick Viñales ended the test as fifth fastest, though it was also with mixed emotions. The Monster Energy Yamaha team had a very full testing program, but they did not have any major updates to test. It was the hard and painstaking work of going through lots of little changes in search of turning lots of small improvements into much more speed.

"We tested many items but nothing incredible, so we have to keep working to try to find something," Viñales said after the test. "I did a lot of laps on race tires which is not bad. I rode quite good at race distance but anyway we need to keep improving." He also tried Yamaha's new swing arm spoiler, but said he felt no difference.

Some of the updates were hardware, and some were electronics, Valentino Rossi explained, and a lot of it was focused on trying to improve traction and acceleration on corner exit. "We try to improve the rear grip, try to improve the acceleration, we worked on the electronics," Rossi told us. "We don't find nothing fantastic but some small details that we will use in the next races."

The one thing Rossi did do was a longer test with Yamaha's latest aerodynamic package, the double winglets which Maverick Viñales has been using all season. These helped more in preventing wheelie, but that improvement came at the cost of top speed, Rossi said, though he intimated that the compromise was worth it.

"The wings are effective, especially for the wheelie, because during the race especially behind the other bikes I suffer a lot with wheelie," Rossi said. "So we tried the wings and they are not so bad, we can use in the next races. It’s difficult for the top speed, because already the top speed is not fantastic, but it can be an option."

Spoiler spoiled

Suzuki also tried an aerodynamic update, though for them, it was their version of the swing arm spoiler. The test of the spoiler was not a great success, however, as Alex Rins ran off into the gravel at Turn 8 and broke the spoiler. "We had a small problem because when we tried, I ran off at Turn 8 and I need to say sorry to the Suzuki guys because I broke it in the gravel!" Rins joked "Then I did two or three more laps with it broken, because I didn't know." The one thing he had learned from testing the spoiler was that it made the bike more unstable when it was broken. Rins is developing a sense of humor.

Suzuki also tested a new swing arm, and both Rins and Mir deemed it a success. "It's a little bit more stable," Rins said. "The swing arm is very similar, but in the acceleration area or in the long corners it is more stable."

Ducati had absolutely nothing new to test, Andrea Dovizioso said, but the test had still be extremely useful. "The setup, I mean during the winter test we had six days this year which is not a lot, and it is not easy to try everything you want, and after some races you can understand something more," Dovizioso said. "It is always important to have a relaxed time like today to test something just to have an idea. Not to improve the bike. You can have a clear idea about the changes you make and the effect it has so you can use in every situation and at every track. Today, most of what we did was that."

The positive point for Dovizioso was that they had not found any huge gains which they could have benefited from during the race. "This means we worked in the right way during the weekend," the Italian said.

Engine configurations

Probably the busiest factory at the test were KTM, as usual. That they were testing something major was apparent by the fact that at one point, when Pol Espargaro came into the pits, he was surrounded by a huge crowd of orange shirts listening eagerly to his every word. On Monday night, Espargaro revealed that they had been testing different engine configurations.

"I am pretty happy because KTM have been working a lot during the winter and brought some things that we couldn’t test in Le Mans," Espargaro said. "A little bit in Le Mans and then here, it’s a problem of the first races of the year to start so far away but happy with the result. In some areas on the engine we have improved quite a lot and also in some areas of the chassis. Not unluckily, but we needed to test on the test because we had not so much time during the race weekend, which is normal. Happy with what we are going and the way we are taking."

The benefits were both in chassis and in the different engines, the Spaniard said. "I think it was a balance. We started with chassis and by the end of the day we switched a little bit to the engine, trying different configurations which I cannot explain to you not because I don’t want but because I don’t know how to explain it to you these configurations but all of them are working good and we are happy. But still with the new configurations of the engine we have more room to play with than we have more room to improve, which is good and keeps us a little bit more positive than before."

In search of balance

Some of the improvements were also aimed at helping Johann Zarco feel more comfortable with the bike, and especially to give him more confidence with the front end of the KTM. "I think what we wanted to and what the technicians wanted to give to me was that possibility to feel better in the fast corners and relax myself in the fast corners because I feel the bike can come easier and have easier control into the corner," Zarco explained. "We got something like that. Working on the front of the bike helped me to feel a little more freedom in the fast corner. From that we tried to make improvements with the rear. The front improved another time so we could work a bit more on the rear but there was nothing really we could find this afternoon."

Trying to find improvements at one end of the bike without losing out at the other end was hard, Zarco said. "I think if we have to use the bike at 100 percent, or if the top guys are 100 percent, which is the target, and then we split between front and rear I would say we are now over 50 percent with the front, and having 70 percent using correctly. Now the rear sometimes is acting as the good one but with the step we did with the front maybe we have lost something with the rear that we must find back. The rear wheel is more complicated to control so it’s less than 50 percent, I would say."

Most of the riders also tried a new medium tire for Michelin, using the same compound technology which has been introduced for the soft and the hard tires. The reception was overwhelmingly positive, the tire giving good grip and more consistency.

With the test done, the teams are now all packed up and headed to Le Mans. They get another chance to test after the race in Barcelona, some six weeks from now.

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This year and testing is all about the Yamaha for me. With optimal track conditions and electronics as focus, it is difficult to see what is going on for them at this time.

The race however displays a much improved bike. The weather was hot, and tires lasted race distance. This is a big deal in and of itself. Drive out spin looked much reduced. The battle with Rins/Suzuki offered a measuring stick. The Yamaha used to have plainly visible to the eye spin, and during the Jerez race did not.

Morbidelli looked to have some drop off of rear tire for the last handful of laps. Vinales did not. Quartararo (poor kid!) we won't know, his shift linkage stuck at about the same time that Franco's laptime sagged.

Much improved start for Vinales, but this issue has less to do with the bike and more to do with his comfort level. But improved braking and corner entry feel can assist him not tiptoeing around in early laps, and it is a safe bet that he is feeling better about bike feel recently.

I do not interpret Yamaha's not throwing parts at the bike ala KTM as a lacking. They are being methodical and focused, and electronics plus some set up changes are the incremental steps needed. The tone of Vale and Maverick indicate progress. They are more settled, not crying out for more, saying good things about the European test program. Both are nose to the track and trying hard.

Having FOUR fast riders on the same machine is a huge help for Yamaha. The aqua kids are a strong motivator for the older guys. Vinales looked spot on focused and exploring the limit while chasing them Sunday. As he came in touch with them he had a few wild movements on his bike. I feared that he was red misting. But he settled in and banged out the laps. One near-clip of an aqua rear wheel, but within bounds. Vale is getting a wonderful motivator from the Petronas kids too, one much better for him than just opposition with Marquez/Honda. He does well mentoring and connecting. Nice to see him battling with Morbidelli, AND teaming up to develop a bike.

We know the Ducati is making good steady progress. This is a big deal as well. The bike turns! So stable. The opposite of a Honda used to be a Yamaha. Now, we have a three point triad of bike design. Suzuki and Yamaha share the blue corner of the triangle. This is REALLY interesting!

In the Honda corner there is of course the Marquez factor. The bike dynamics don't change factoring him out, but the battle of bike design/development does a bit. Especially with a bit of a lingering question mark of Ducati riders, as they don't appear to have a single stand out rider. Huge respect to hard working Dovisioso! And still an indication is there that this Ducati is a great bike that we could see that next bit from. The whole Gigi era bike transformation continues to be remarkable! As was the Red MotoGP entrance years ago. They keep doing it, hats off to them.

The KTM and Aprilia are oblong outliers at this point. Neither approaching the big three. The Aprilia just doesn't have the resources, and are doing well to be on the pace. They have taken a Superbike and made a MotoGP bike of it. KTM, their bike is literally behaving like a Superbike. They have taken a Moto3 and Moto2 platform and extrapolated bigger with the most roundabout route to handing riders a bike that behaves like Jonathan Rea's. The steel trellis frame AND in house WP suspension are big bites to chew. Doubts that this formula is going to work here are founded. It is still a toddler of a project. Wishing them luck. And wishing that Zarco's new coach take good care of him for the duration. Desperate times for him, VERY hard to stay motivated and focused in the game coming from a great handling bike last year to this thing. Both Espargaro brothers are doing solid performances with the machines, as highlighted by gapping good teammates consistently in many conditions.

Eyes on track conditions and the Yamaha at LeMans. Better hurry with that write up David, the milk spoils left out like that mate! You might flip to a hybrid plan where the basics half a write up comes right away, strike while the iron is hot...with a lead in teaser on specifics that will get further unpacked in the follow up. Have THAT one be the subscriber content. I am concerned that the site will lose some engagement and vigor with this plan now, Sunday eve thru Wednesday the news has holeshat. Do a Jorge start, not a Maverick one?
LOVE LOVE LOVE your work!

(P.S. please move the "save button" back where it was on the next site update?)
Thank you,

Re when to publish write-up vs subscriber content:  I tend to agre with Motoshrink, although I hesitate to advise David on his business plan.  Us subscribers are the obsessives, and willing to wait for the detailed analysis. But perhaps the traffic volume comes in the first 48 hours after the event, and it might be wise to publish a quick write-up for the world+dog then?  

But as I said, I'm no online business consultant :-)

I would agree with earlier comments re: timing vs subscriber/non-subscriber readers.  To the point - the summary details, rider quotes, big news stories you can find many places on the web (eg. The quick write-up would meet that content provided by other sites. The longer subscriber article is something you don’t get anywhere else. This is a write-up of the intimate stories and details that paint the picture of the race. Having non-subscribers read the ‘highlights’, but miss out on the ‘real meal’ is where it’s at. 

Also love, love, love the work. The week after a MotoGP race would be a much sadder week without a write-up from MotoMatters!

The reason for the switch to this format is quite simple: I am trying not to kill myself. The long-form race reports are often in the region of 8,000 words, and take between 8 and 12 hours to write. On a Sunday night, that is just not possible any longer, and my health was starting to suffer as a result of trying.

My thought process is as follows: Subscribers pay, and so deserve to be served first. So I try to put together my initial thoughts, and stuff I noticed. The big story on Sunday was obvious Quartararo, so there is not as much in this as I would normally have written. The long-form round up will get written when I get around to it (probably Thursday, published Friday morning) due to the test and travel times. I would like to keep those free, but by giving the subscribers something early, I feel less bad about writing the race reports much later.

Of course, if I could double (or preferably triple) the number of subscribers, then I could hire more people to help, and spend more time writing. But that is a long-term plan, which will take a few years to come to fruition. I will write a blog about some of these plans soon, and take suggestions on subscriber preferences, and ideas going forward.

David, I understand the rationale of "subscribers pay, so serve them first".  As a subscriber, my perspective is that what I really love about your writing, and what I'm willing to pay for, is the depth and breadth of both access and analysis that you provide.  And I know that takes time, and I don't mind waiting so much for that.  

But I'm just one subscriber, and I'm sure you know your audience better than me.  And you absolutely need to look after your health - we need you!


My first ever post here, just to add one more "subscriber data point": I didn't subscribe to be "served first". Although that is always nice, I appreciate that your health comes first and so there's trade-offs to be made. The reason I subscribed (and just renewed it, as well), is to get access to all the detailed analysis and "subscriber only" back stories.

So that's one more vote for "serve the big talking points (in summary form) early, keep the in depth analysis you can't get anywhere else for later in the week and subscriber only" -- or maybe subsriber only at first, then public the week after or so, to make non-subscribers aware of what they're missing.

Please feel supported David. Been aware that you were over doing it on Sunday nights for years and sent appreciation your way.

Perhaps a "less is more" for the first partial report, and build some food for thought that gets us involved and checking back in. Open a few insightful questions, as opposed to flesh out all answers. Then do your usual for the second part. Watch the clicks roll in.

Like the false dichotemy of riders being to stiff or forceful on the bike. Gripping tightly. It makes it run wide. They get exhausted. Front end feel is down. They enter a corner downshifted a gear too far. Front end washes out.

Wag the elbows like a bird approaching braking. Anchor with the lower body and core muscles. Go in one gear higher. Notice the turn-in point...going to hit it? Reach awareness through to the apex sooner. Mind the foot pegs, step on the inside one entering. Rest that outside forearm on the tank. Crack throttle open and feather the gas on, reaching towards the apex. As soon as you know you are going to hit the apex, THEN reach awareness to drive out exit point. Mind the outside peg. Dani the bike up a bit. GAAAS.

We can't have too much going on in the first part of the corner or we get apprehension and bogged down. Then a bike then confirming our concern by being unsettled. The outside lats and shoulder muscles get over used holding us off, apprehension. Awareness fixates, both too diffuse/vague AND partialized to the corner entry. Only of the upper tight parts of the body, and again diffusely. We can notice the apprehension that has us ridgidly adhering to this. It is a defense, taking care of us to date. It is onviously nuts to careen a motorcycle at a corner at speed, as to craft ones own innovation in a big corporate world (your site is a Britton!). Soft grip on the bars, looser arms/shoulders. Allow the front to wiggle-hunt for traction after chucking the turn in. Saying yes and leaving more to the bike fore-aft carving on compressed suspension. No more steering inputs. Light touch of throttle drives the rear wheel down. LESS GOES ON AT ONCE. The whole corner has flow, we did less. The bike wags its tail under deeper braking next time like a happy dog, since the whole corner carves balanced with both tires like a Marquez two wheel drift. BrAAAap!

Humbly submitted, NO ONE is doing the superlatively excellent journalism in the motorcycle racing world that you are doing David. Not one person. (I started my own psychotherapy practice, no guidance, doing very innovative groundbreaking work). Like racing a bike you built, no mechanics. Out there on the track at speed. Bridging the earth and sky. Fantastic. Perhaps each race weekend coverage is like a corner?

All the best, friend. We are here with you.

Hi David

Nobody wants You or Anyone else to have Health Issues.

The main reason people are here is to read your insights & round-ups when the races or event is fresh is our minds.

So it's now nearly Saturday or 1 week after the race, which takes away the whole enjoyment & relevance of reading your round-up after following the whole race weekend

Perhaps you can post the full race round-up on Mon/Tues for Subscribers Only ? and then release this a week or 2 to non-paying subscribers ?

My subscription has just ended and i haven't renewed it as yet only because of this ... hence my suggestion to either just make the whole site subscriber only so the paying members can enjoy the site how it used to be or to at least have the best parts which we love - the round-ups & analysis  as paid content delievered in a timely manner.


As now the best part is free but takes too much time to be posted ... so as this delay keeps haapneing it might result in people just not wanting to do the continuous refreshes that we do daily . for days or now  weeks ? till the round-up is posted..

For Last Race when the round-up was delayed by a week - it lost the whole relevance & did not have the same enjoyment for me that i would get if it comes in reasonable time after the event is finished ...

I might be just 1 member posting/writing this comment but i am sure there are many more members thinking/feeling the same thing ...


Just for balance, I take the opposite view - timeliness is the least important thing to me. I'm more than happy to wait a week for the dust to settle, and for David to gather his thoughts and post his in-depth analysis

If I write the full race round up on Sunday, I will be finished around 10am on Monday morning. As I get older, I simply can't physically do that any longer. Especially not after 3 or 4 days of 5 hours of sleep. 

So even if I wanted to, I could not put your idea into practice. I can manage between 2000 and 3000 words on Sunday night. That either means the notes format which I am now writing, or a significantly shorter race summary which won't add much to Zara's report after the race. 

Hi David

I think you missed my point ...

1>The idea was to post the round-up quicker than a week not for you to post the round-up on Monday ... so maybe somewhere before wed/thurs

As for sure given your travel and other commitments it might not be feasible to do the full round-up on sunday night after the race in-time for Monday morning reading.

2> Making the whole site subscriber only for the $40 which i feel will make all of us sign up to read your insights & will give you the needed financial benefit & incentive

3> Make only the Race Round-ups/Analysis Articles subscriber only for the first week & release it later for non paying members for the same reasons as point #2

Anyways the whole idea of my comment was to think of ideas to get you more money in place so it works for both - you the writer & us the readers ...

I must say, I have a problem. Do I post my "pithy" comments on the quick post race report or the one that comes days later. Frankly I'd prefer to do it on the quick report, but then the comments get burried once the long report comes out. I care not a whit about being served first or not. I'd give the world the early short report and save the longer one for subscribers. That said, I find the 2 reports dilutive, but understand the health issues factor. Perhaps you can compromise and give us a report before wednesday or thursday with nothing more than a race result on the day of the race. 

For the factory Yamaha team, in search of corner exit grip, when presented with an opportunity to test directly after a race, is it possible to fit the rubber used in Sunday’s race to compensate for the fact that the track is well rubbered in and warm?

That probably sounds hilariously naive, but the rubber should be well past its best and ready to replicate the issue they are apparently trying to correct. Or maybe Michelin collect the race-used tires for analysis back at the factory, rendering my naive question moot.


KTM need to build an aluminium frame before their investment in Zarco dissapears. I would be impressed if they tried, as their steel tube frame is just hurting everyone. Good luck and don't give up, but a word with Mr Suter would be a good idea.


Great point, but that train appears to be leaving the station as we type. Unfortunately, some of Zarco's comments on the current state of KTM performance were caught on video this last weekend, and while translations can always be subject to error, the gist of it was Johann describing his KTM as having a "...shit engine surrounded by a shit chassis...". This did not go down well with KTM management. I imagine that almost all MotoGP contracts have performance clauses, and it would not surprise me for KTM to cut their losses with both Zarco and Syahrin, two year contracts be damned. When you are spending a fortune of your own...and, the term "ruthless efficiency" hangs over every conversation. And while I am a huge Zarco fan, it becomes blindingly obvious that things need to improve before Herr Mateshitz  starts to wonder...out Suzukis would look in Red Bull colors.

Regarding the use of aluminum, I agree. But not in the commonly described manner of a another twin-spar design. No, I would prefer that KTM take the expedient route of using an aluminum trellis instead of a steel one. But why? High performance aluminum and steel alloys have very similar stiffness-to-weight and strength-to-weight ratios, so what are the advantages of an aluminum trellis over a steel one (other that being safe from the menace of refrigerator magnets)?

"Isotropic" is a lovely engineering term that translates as "equal properties in all directions". "Anisotropic" is an even better term, and describes a component or system that has different properties depending on the direction of applied force (or thermal gradient, or exfoliation, and so forth). And for a MotoGP chassis, Anisotropic is what you want. And that is what you get with an aluminum twin spar design, especially at the top level where the "spars" are almost certainly internally machined to fine tune these properties. Correctly done, this can provide an excellent balance of fore and aft stiffness (for braking stability), torsional stiffness (for roll in), and reduced stiffness side-to-side (to both absorb bumps and let the rear hook up when leaned over). The Suter comment was spot on the money, and if you visit their web-site they show some pretty nifty examples of the art of all this. Round steel tubes are, by their very nature, pretty much locked into an isotropic properties mode, though the chassis, as a whole, can be made somewhat anisotropic by the layout of the geometry, and by varying the diameter and wall thickness of individual members. But substituting aluminum for steel has an additional advantage. Greater wall thickness.

An aluminum tube of equivalent diameter as a steel one will have a greater wall thickness to achieve the same mechanical properties. This would, at first glance, appear to be a negative, as any tube will be more efficient with a greater percentage of mass distributed away from the neutral axis. But motorcycle chassis are not lab specimens. They have quite a number of tasks that become more difficult when wall thickness becomes very thin. Engine mounts, swinngarm pivots, and head stocks will need to be quite a bit thicker than the connecting tubes. This is, at best, unpleasant for engineers as those thin tubes do not care at all for sudden large steps in wall thickness (they act as stress risers). Add all of the associated bracketry for the fuel system, airbox, electronics, etc, and you are stepping wall thicknesses up and down all over the motorcycle. Kevin Cameron captured this (about 35 years ago!) as one of the drivers that led to the switch (from steel) to aluminum racing frames. The steel frames (even the early rectangular tubing ones) were so thin-walled that by the time you built up all the necessary transitions needed to support the totality of functional requirements the expected weight savings largely disappeared. Aluminum sections, having a native thicker wall, needed far less change in the transition zones and were, as a whole, lighter and easier to fabricate. And that was due almost entirely to their more rational wall thicknesses, not any magic properties of aluminum.

So how does KTM build a truly anisotropic trellis frame?. Well, to my simple mind, being able to precisely alter the wall thickness along the length or cross-section of any member is where you start. Can't we do this with steel?. Well, sorta. Certainly steel racing bicycles have used varying cross section tubes for decades. But their application remains fairly simple, and simple ain't cutting it in MotoGP. The very nature of a thicker aluminum tube would enable KTM to internally machine their trellis members any way they want. I imagine the result may be a round OD with a tapered oval ID (with perhaps a bit of twist in the oval). I suspect the steel tubing they are currently using is so thin-walled that they are very limited in that respect. The use of the less efficient thicker wall of Aluminum members actually results in a more efficient end product (after machining), which may sound contradictory, but it also sounds a lot like "well, that's how things work, mate".

So which design is best, spar or trellis? Easy...the one that best transitions to additive manufacturing (AM) techniques (which may very well be "none of the above"). Additive Manufacturing is the entire range of processes that include the layman's generic term "3D Printing" (3D Printing is just a small subset of the AM universe. All the cool kids call it "AM", not "3D Printing"). MotoGP Chassis' would appear to be an orchard of very low-hanging fruit from an AM manufacturing process standpoint, and you are going to start to see it...sooner than we might think. In the mean time, the KTM is overweight and Zarco says it is shit. But if you switch to internally machined aluminum tubes...and then slather it all with orange paint...KTM pride is salvaged and life gets better for riders whose style requires a more laterally flexible platform. I can see KTM's reasons for wanting to continue down the path of a trellis design, but not in steel shoes. Cheers.

Jinx Thinks
Zarco, oof. Thanks for sharing that.
Just like Dovi in the first corner Sunday, so many fast kids are swooping in to MotoGP now that he is at risk of no Ducati/Honda/Suzuki/Yamaha seats being available for 2021. It was a mistake on his part to expect otherwise w this bike for now. And a bit longer now too. EVERYone knew so. Big shame, Zarco is proven top step talent, which is a very rare treasure.

Nice frame material geeking. I hadn't even thought of Alum trellis. The KTM model is centered around DIY in-house. Very admirable! But, too much bitten off. Doubt they can in-house build aluminum. Zarco is right though, this bike is out-house.

Did you see the Speed Up project got pole and a 2nd in Moto2? Nice to see.

I'll have to throw the "AM" bomb into a conversation....and then stand well back, lol.

Your (and Kev C's) thoughts regarding the "rationality" of steel frames has Ducati springing (no pun intended) to mind.  From 851 to 1198 their steel trellis frame was a winner in WSB. 

Old news?  Not really, Checa absolutely dominated the 2011 WSB championship on a restricted underpowered privateer Ducati 1198 against Biaggi on the Aprilia RSV4, Melandri on the R1, Haslam on the S1000RR, Rea on a CBR1000RR in it's prime. 

He started off the 2012 season with a hiss and a roar too, but mechanical failures cruelled his championship chances. 

The bikes he beat aren't Olde Tyme bikes of a previous generation, the RSV4, S1000RR are only slightly different even now and also had MotoGP refugees aboard with Factory might behind them.

Yet the 1198 frame was basically a larger tube/thin walled version of Tamburini's magnus opus of '94.

Not saying I disagree, just pointing out a fly in the ointment.

...and to add to the "why I subscribe" posts - it's also because of user/member posts and opinions like these!  I dig the comments as much as the journalism!  

Very informative, thank you.

To be honest I can’t think why anyone is still using steel these days, with all those fancy alloys out there. It can’t be materials cost, that must be a fractional consideration in this game, nor machining challenges. Can anyone enlighten me?

There's no point learning a lot about something that has no application for them, and they learn nothing if Mr Suter does all the hard work.  So a steel trellis it is.

This project is basically KTM's "NR500" moment.

The motoGP rules are very restrictive when it comes to materials: Materials
NB. “X-based alloy” or “X materials” here means the element X (e.g. Fe,
for ferrous or iron-based alloy) must be the most abundant element in
the alloy, on a % w/w basis.
1. The use of titanium in the construction of the following parts is
• The frame/chassis, excluding bolts and fasteners (the decision
of the Technical Director will be final when determining what
constitutes a part of the chassis).
• The swinging arm, excluding bolts and fasteners.
• The swinging arm spindles.
• The wheel spindles (for wheels spindles, the use of light alloys is
also forbidden).
• The handlebars.
• The front suspension inner and outer tubes and bottoms
(ie. axle mounting point).
• The shock absorber piston shaft and damper tube.
2. The basic structure of the crankshaft and camshafts must be made
from ferrous materials, steel or cast iron. Inserts of a different material
are allowed in the crankshaft for the sole purpose of balancing.
3. Pistons, cylinder heads and cylinder blocks may not be composite
structures which use carbon or aramid fibre reinforcing materials.
4. Brake calipers must be made from aluminium materials with a modulus
of elasticity no greater than 80 Gpa.
5. All connectors from the brake hose to the brake calipers (front
and rear) and the brake master cylinders must have structural
components (*) manufactured from either steel or titanium alloys
with a tensile strength no less than 500 Mpa.
* Brass connectors are are permitted for rear brake hoses only.
6. No parts of the motorcycle or engine may be made from metallic
materials which have a specific modulus of elasticity greater than
50 Gpa/(g/cm3).
7. The use of MMC (Metal Matrix Composite) and FRM (Fibre Reinforced
Metal) materials is forbidden.
8. In the MotoGP class, hollow structure connecting rods are not
permitted. Oil galleries of less than 2 mm diameter in the connecting
rod are permitted.

Once you factor all that in, you're very much stuck with steel, aluminium, and carbon for the frame.  Carbon on it's own is too 'dull' - as Ducati discovered.

What a strange mish mash of rules. Presumably to deter the horrendous cost of pursuing unobtainium. Thanks for the explanation though, I didn’t know that.

I don’t watch the races or subscribe to anything except MotoMatters, so I do like to see results and a brief summary, ideally with a little bit of insight and thoughts, as soon as possible. However being an old guy who remembers waiting a few months to even see results, let alone details, in print here in the US, I’m willing to wait a few days, or even ten days, to get David’s full analysis. Quality over speed, in other words. As for Zarco, and Iannone for that matter, I think their days as front-runners in MotoGP are over. We’ll see them in WSBK soon. And I’m excited to see Fabio, Franco and Alex challenging for the podium. I thought we’d have Jorge and Vale, along with Dovi and Cal, as MM’s top competitors this season but it’s a much bigger group of contenders and that’s great for us as fans. I’m still hoping for a few more wins from VR46 before the kids take over, though. 

David, you can ignore this which I'm sure you will but what about limiting content to X number of articles per month for those who are not site supporters. I must say that I do like the pre-race reports but if I had to pick I would probably stick with the longer Round Ups, even if it's 2 or 3 days later. 

Frankly, there's nothing that I enjoy more than showing up to work I hit refresh to the MM website and there's that new article that means that the first 30 minutes of my day are anything but productive as I'll be enjoying my coffee to the tune of David narrating the race. 

Now, as it relates to Jerez... here are my thoughts (not that anyone cares):

- good to see YAM improve and agree that we're in for a treat with Morbidelli and Quatararo yet I find it interesting that it's been 3 years and we still haven't seen a Vinales/Marquez fight and that I would love to see

- is anyone afraid that Marquez has dominated the whole season? Just a couple of hiccups that have caused the championship to be this tight but one race he's fighting with Dovi, the other with Rossi, etc. The other names change but his is always there. I'm not a fan of the guy but man, what a talent! 

- can Aprilia bring back Bradley Smith as a Factory Rider? the guy is passionate about racing just like Iannone is passionate about makeup and modelling

- KTM, someone needs to give Zarco a "bitch slap" (sorry for the word) but he needs to quit whining and just ride, he's got the talent but is facing all sorts of demons, can't wait to see them take a well deserved podium