Tech Details From Portimão: Holeshot Devices, Handlebar Switches, And Sensors Galore

MotoGP starts are busy affairs nowadays. On the top triple clamp of Pecco Bagnaia's Ducati GP21, the front and rear holeshot device switches

Ducati's front holeshot device is visible here. The aluminum clamp above the fork seal holds a plate with a latch. Below, the two cables which engage the device. Also visible, the suspension stroke gauge, and the teardrop aerodynamic fork covers

Clearances are very tight on the Ducati, as the scorched fairing lower next to the exhaust shows. The Ducati's always smell a little singed when they enter the pits

Yamaha has been working on aerodynamics to improve top speed. These wheel covers remove some of the turbulence created by the spinning wheel. Duct tape covers the air inlets, needed to cool brakes in hot climates.

Ducati's wheel covers are smaller, focused on the bottom of the wheel. But teardrop fork covers are much larger, clearly visible here. Sensors are on the left-hand side, including brake temp, 2 speed sensors, and an accelerometer on the bottom of the fork, to track axle movement.

The Suzuki is simplicity itself. Top is the hydraulic clutch master cylinder, below that the output sprocket and torque sensor, and water pump below that

Valentino Rossi's 2021 Yamaha M1. The frame number is a giveaway, but so is the weld above the rear engine mount

Franco Morbidelli's 2019 bike doesn't have the weld, betraying its age. Data cable attached to read out the datalogger

No triple clamp switches on the KTM, only the attachment point for the rotary steering damper. Thumb brake on the left, and neutral engagement lever on the right

Swingarm contrasts - the Suzuki's shiny and elegant aluminum unit

Ducati's carbon fiber unit, completely with rear wheel cover and load sensor on the rear sprocket. That sensor is only used during practice to set up engine maps

The factory Yamaha aluminum swingarm - the weld is the tell. Compare the open rear sprocket to Ducati's below

More aerodynamics? Webbed Ducati sprocket instead of completely open. That may help reduce turbulence from the rear wheel

Suzuki's stunning Akrapovic exhaust, and dry clutch.

Engine seal on rear cylinder head, and scrutineering sticker for Johann Zarco's #2 Pramac Ducati GP21. Note the scratches on the exhaust lower too

The Yamaha cockpit: on the right, pit limiter and engine cut button, and neutral lever. On the left, engine brake and torque map buttons. Bottom lever is thumb brake, clutch lever is not visible, and at the top the Yamaha holeshot lever

Placement of the holeshot device lever suggests that Yamaha are using the system as a 'shapeshifter', to adjust ride height on track. The lack of such a lever on the Ducati suggests they have found a way of automating the operation of its shapeshifter.

Where the magic happens: each year, Ducati's so-called 'salad box', or tail unit changes shape, and presumably, alters its function slightly

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Holeshot device mechanism (partially) decoded!  For the front of the Ducati, at least.  Since there isn't any electronic hocus-pocus allowed in regard to these systems, it would be interesting to know how (if) the Ducati system has been automated.

Clever engineering solutions like that are mentally so far beyond my grasp that I feel I should go to the garage and burn all my tools.

I believe that's a slave cylinder (not a master cylinder) on the Suzuki left side picture. Great pictures!

 As to suzuki's sprocket torque sensor, I recall David writing about Hondas "torductor" back in 2014 :

It is a rather neat little irony that HRC appeared to have replicated the downshifting behavior of a two stroke on a 1000cc four stroke, though at an astronomical cost.

... scooter brake setup on a supermoto or even a sportbike. I'd guess it would be really intuitive once the rider became accustomed to it.

Agreed! My feet are busy, and not so sensitive. Nearly never touch mine. When I DO have a scooter brake, I use it to settle the thing and brake harder. 

Such mixed feeling about the Ducati. Complexity and very interesting. Innovative. "Cool" looking, makes you want to closely examine and ponder.

But...ick. You know? Tail in particular. Sounds that riding it is similar? The more riders that get on it over the yrs, the better CS27 looks.

I recently watched the Troy's Story documentary narrated by Ewan McGregor. So many of the same characters around at Ducati. Bayliss had the attitude, the head, and the talent to work with the Italian organization's WSBK crew back then and bring home the victories. He believed he could do it and they did too. No doubts. Watching the documentary and listening to the interview with Troy and the crew it all seemed to work. Then I think back to Casey's time in MotoGP with Ducati - how they treated other Ducati riders while Casey was winning and what happened as Casey became ill. That left a bad taste in my mouth, and its a taste that never seems to go away. 

I have seen that a few times too Joshua. Good insight into him then, eh? Driven. His one off Wildcard return to blitz the field and win in an era in which a palmful of riders were winning was a brilliant favorite! Some of the best WSBK we have ever seen too w he and Edwards. Incredible stuff.

100% agreed that Duc screwed the pooch w Casey. Some compassion and understanding towards all of them re lacking the same towards Stoner. It was not diagnosed partially because it was so atypical (lactose intolerance is usually very different in presentation, lower G.I. focused, his was extreme fatigue). Interestingly, Casey's plain and very honest "who knows?" way of interacting with management was something they pushed against. NOT smart. They were also proud and over convinced that their bike was the better part of the Red #27 equation. Stoner was worn down by the media demands, a more sensitive and quiet matter of fact type. Especially the personalized drama of perceived problems between he and a rider or two. And then came the health issue. Then a conflict w Ducati that was handled poorly at best. Really unfortunate! We lost a treasure. 

Anyhoo, looks like a shift has happened w riders at Ducati. And the bike can turn better. May be having an easier time being set up for various tracks, and bogey tracks not sending it back so bloody far down the order. Jury is still a bit out, isn't it? Bagnaia is making it look pretty flickable even at Portimao. Hoping they do well next Round. 

I'm wondering what the pair of forceps are clamped onto on the Suzuki. As seen in the pic of the right side rear section (the fifth photo from the bottom), jutting out of the window in the tail section. I've noticed forceps clamped onto the bikes at other times, but it's usually up at the front.


Also: thanks very much for this post! I quite like seeing these kinds of detail shots of these bikes.

Thanks for that tidbit. That would definitely make sense, though I've never seen them with the tag on.

Ben Spies got caught out by someone not removing one of those clamps in Estoril....He removed it himself during the race...

Looks like it could be holding the loose end of a disconnected cable from disappearing into the bodywork?

Pretty sure I've seen them being used to clamp a fuel line (breather/overflow?) on the grid. Someone getting fuel starvation from it - maybe the Spies incident as mentioned.

Two pictures had me puzzled: the duct tape on the wheel covers and the brake temp sensors on the duc: would it be allowed under the current regs to have a set of variable inlets, based on the feedback from the temp sensor? That way you would be able to optimise the brake temp and possibly improve braking action. You could even (if the info was sufficiently precise) vary the action in the braking phase for upright vs banked braking.