Tom's Tech Treasures: Carbon Swingarms, New Seats, And Sensors Galore At Le Mans

Thomas Morsellino is a French freelance journalist and photographer, with keen eye for the technical details of MotoGP bikes. You may have seen some of his work on Twitter, where he runs the @Off_Bikes account. Peter Bom is a world championship winning former crew chief, with a deep and abiding knowledge of every aspect of motorcycle racing. Peter has worked with such riders as Cal Crutchlow, Danny Kent, and Stefan Bradl. After every race, will be publishing a selection of Tom's photos of MotoGP bikes, together with extensive technical explanations of the details by Peter Bom. subscribers will get access to the full resolution photos, which they can download and study in detail, and all of Peter's technical explanations of the photos. Readers who do not support the site will be limited to the 800x600 resolution photos, and an explanation of two photos.

Carbon swingarm on Pol Espargaro's KTM RC16
Peter Bom: Interesting to note that KTM's first attempt at a carbon swingarm gave an immediate improvement. At Aprilia, for example, we have seen a number of different prototype carbon swingarms, but the riders have so far always reverted to the aluminum items. Apart from the weight – Pol Espargaro says the bike is still around 5kg too heavy – carbon fiber has one major advantage as a material for a swingarm: you can modify stiffness in both force and direction just by changing layering, using the same mold. Producing a mold can be expensive, but because it can be reused to produce different swingarms, it is still an attractive proposition.

Load cell on the Ducati GP19, used for the quickshifter
Peter Bom: The red cylinder is a so-called load cell. It measures extremely precisely exactly how much pressure (in compression or tension) is being put through it. This information is used by the ECU to make changing gear up or down easier, by cutting the ignition once the load reaches a preset value as the rider presses the gear lever down or up. The sensors used in MotoGP have to be extremely precise, and most importantly, they have to provide stable output even when exposed to severe vibration and high temperatures. The bolt thread on a sensor like this broke on Fabio Quartararo's bike at Jerez, leaving him unable to change gear.

Handlebar of the KTM RC16 (Syahrin) with the new carbon fork used by Tech3 since Jerez

The standard Honda seat on Jorge Lorenzo's RC213V

KTM Moto3, Can Öncü

Yamaha-like carbon rain deflector used on the KTM RC16

A new carbon fiber cover used on several Kalexes, this one on Sam Lowes' Gresini bike

Carbon cover for the brake fluid on the KTM Moto2

The 2019 aero package on Franco Morbidelli's Petronas Yamaha SRT bike

GP19 front wheel with several sensors (disc temp., gyroscopic sensor, wheel speed). Note the titanium screws

Special livery for France, replacing "Mission Winnow"

Honda RC213V steering damper on Cal Crutchlow's LCR Honda

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I would like to better understand this: "The both thread on a sensor like this broke on Fabio Quartararo's bike...". Thank you.

This is something I tell new racers when they ask me "do I have to safety wire thing xyz?"
I'd love to see pictures of the broken sensor and see if it broke or backed off. I've had the lock nut on my shift rod back off, and dangle during a race. Hence why I safety wire the lock nut, even though it's not required. 
Is it me or does the color scheme on the Petronas bikes with the new aero make them look like fish? They look like gils.
I'm sure somebody with some graphic art talent could make Franchi look like he's riding a shark.


Fabulous close up shots. What is that cylinder like canister that is attached to the exhaust header (it appears below the lambda probe in the pic)?

that Jorge Lorenzo finds it more necessary to freely move around the Honda than with the Ducati, ref. images 4 and 4a.

Is this:

1) because the machine is different?

2) because he needs more leverage to make up for a lack of upper body strength (because of limits to his workouts caused by the injuries)?

3) a combination of both?

I imagine, from having been a rider (and wannabe club racer) that the Ducati situation, with the high friction seat, was more of a one-off than riding other machines?

And thank you very much for the images and the commentary (captions).

Getting on the Duc he was braking harder rather than carrying the speed into the corner as with the Yamaha. To get more comfortable there, he got a tank extension in to his inner thighs to grab, and a stickier seat to hold his hams in place. Then this year on the Honda, the same is true re the braking, but his injury prevented him from being as fit/strong as he can be so the muscle needed for MotoGP "holy cr*p these things stop" braking is still a place he needs support. The Honda moves around a LOT more than the longer Duc, so most riders are moving around on it more. It is a really athletic event to ride that thing hard.

The grip adhesion used looks a bit hodge podge. There are two basic styles, the pokey-point stomp grip style, and the TechSpec friction style. I noticed that the KTM project is using TechSpec. They have several varieties, I use the same kind that KTM is running on ALL my bikes and tend to add it in places beyond the usual where knees wander on the slower turns. Now, I can't effectively ride on a bike without it. If you aren't running a good tank grip you are missing out. Try adding some to the frame just past the tank cut out too, it feels GREAT.

Excited for Mugello!