Get down to go faster
Motogp technical expert Neilspalding is certain Ducati are experimenting with a lowering device, and there’s but one reason for this. To go faster…
At extremely high speeds, motorcycles want to roll over backwards. The centre of pressure on the front is typically higher than the centre of gravity, so as speeds increase, the force trying to flip the bike grows too. In addition, at over 200mph the tyres will have bulged to their maximum diameter, reducing the contact patch. Then, at places like Mugello, there’s a crest thrown in too – welcome to the world of the 200mphplus ‘wheelspin wheelie’. Though quite a spectacle, this is suboptimal for lap times – if you can’t get all the power down in a straight line, you have to try harder in the corners and are likely to visit gravel traps in the process. Going fast in a straight line is a relatively easy way to cut lap times. So how do engineers raise the limit where the front wheel starts to lift and the rear wheel starts to spin? Adding downforce seems logical. Over the last few years, since the relaxation of the Motogp fuel limits, wings have appeared on the front of all Motogp bikes. Less easy to see are the way the shapes of the fairing around the radiator have also changed. Now the fairings only trap enough air to cool the radiator, with the rest allowed nd to spill down the sides of the bike – the high pressure under the nose fairing is therefore reduced.
The riders are making changes too. In a world where Motogp bikes have more power than can be used, riders are dragging the rear brake at full chat to pull the swingarm pivot downwards to lower the bike. They may lose 20bhp doing this, but that’s fine because it allows them to use the other 20bhp they have in excess.
At the same time ‘start devices’ have been added. These lower the bikes on the grid and allow a faster start before the ‘wheelie point’ is reached – it’s why drag bikes are long and low. But with the Motogp bikes, a device allows them to pop up again before the first corner. At the 2018 Jerez test Ducati tried a special rear torque arm that joined the rear brake caliper mount to the suspension link. That aggressively lowered the bike on rear brake application but it was dicult to use and it hasn’t been seen since.
Even further back – over ten years ago – Ducati patented an electrically powered ‘active ride height adjuster’ located in the drag link of a 916’s rear suspension. That basic concept could be used in Motogp but not with the electronic controls because the Motogp rule book states suspension adjustments can only be made by ‘manual human inputs and mechanical/ hydraulic adjusters’. Which brings us to the latest test in Sepang, where I think Ducati were trying to reduce the ride height on their
‘Ducati didn’t add all that plumbing to the front of their bike just for the fun of it’
bikes on the straights again. Petrucci’s bike had, stuffed into the bottom of the fairing nose cavity, what looked like an Öhlins shock absorber reservoir and damping controls. This could be pressurised as the bike moves on its suspension and that pressure could then power the start device in the rear linkage, with the rider merely having to press a button to trigger it.
The main shock absorber would have its compression damping ability reduced appropriately and I suspect the rear suspension would be collapsed mechanically or hydraulically and then automatically re-extended and ratcheted back to full length under hard braking for the next corner. I doubt the system would be used to lower the forks, as that would require drilling holes in them, which Öhlins almost certainly wouldn’t approve. There were handlebar controls too, but these are lightweight and must simply be triggers – red for a manual re-extension and green for collapsing. This whole system depends on a creative view of the rule book wording, but that is a skill Ducati’s top guys have no shortage of.
Of course all of this is purely speculation, but Ducati didn’t add all that plumbing to the front of their bike just for the fun of it. There has to be a reason and that reason has to do with going faster.