safety – British Superbike School

As motorcyclists, the problem with young riders is something we are going to have to tackle ourselves. If we want anything to change.

I came across 5 young riders on a single day last week, probably all riding illegally. One had no headlight, 3 were wearing shorts and T-Shirts. Two had proper kit and were riding off-road bikes. Gave me a nod as they passed me on my E-MTB.

If I’d been on my KTM they may well have stopped for a chat.

I trained the Notts police off-road team many years ago, who were very successful in tackling the off-road riding problem. But that is not where the problems mainly are. It’s on road. Off road riding really is just a nuisance – mainly noise, and complaints from land owners. Tractors do far more damage.

So what can you do?

Firstly discourage your youngsters from riding a motorcycle if under 16 years, when they can do their CBT. An E-Cycle or E-MTB can be legally ridden from 14 years. Good chance to learn braking and handling skills – and the use of disc brakes and suspension movement.

They can race mini motos etc. and off-road, but it’s expensive. There are facilities in some areas where they can ride, but sadly they are rare. There is no national equivalent of ‘Young Drivers’. There should be.

Personally I’ve never had a problem talking to young riders. Never had any abuse.

Motorcyclists come from all walks of life, sharing a common interest. If you breakdown roadside the next biker along may well stop to help.

The Problem

In 2022, in the 14-16 young rider age group:-

115 KSIs in total
60 were underage
55 were riding 125cc machines illegally

In 2023, in the 17-20 year old group:-

36 young rider fatalities
50% higher than the 24 fatalities in 2019
Double the number from 2020, which at 18 fatalities, was probably affected by COVID 19.

The extent of the problem seems to be a well kept secret.

The Main Issues

Illegal E-Scooters.

Average rider age 16 years.
50 deaths all ages so far. >1,000 serious injuries.

Underage Riders

40% of fatalities. Many others probably had no licence. Proper training is vital.

Upgrading to a 125cc

The risk of upgrading from a 30 mph moped to a 125cc geared bike capable of 60 mph with no extra training.

No legal requirement for more training. The vast majority of KSI’s are on 125’s.

Emergency Braking.

The DVSA advice is wrong. Apply your rear brake immediately. Do not snatch the front brake lever, or stamp on the rear brake. Apply the brakes steadily. Practice.

Consider riding with two fingers on the front brake lever and clutch, and just squeeze both in an emergency. This should save you >1 sec and critically should reduce your impact speed by around 15 mph or maybe avoid an impact altogether. You’ll probably survive a 30 mph crash, but not at 40 mph.

A New Approach?

I started again, this time with pre-teen riders and Bikeability, who are supported by the Dft.

We already know that there is a serious problem with PTW braking, so I asked them how they teach braking to young cyclists.

Received an immediate response. Somebody cares.

They are taught to ride covering their brakes, how to brake progressively, and particularly to avoid snatching the front brake. Perfect.

So moving to a motorcycle, the skills are immediately transferable.

The question is then why are PTW riders not taught to cover their brakes, and why is PTW braking so poor?

Bikeability cover 44% of younger riders who should be more open to accepting advice before they become teenagers. Braking skills can be embedded more easily with younger riders creating ‘muscle memory’.

There is now also a ‘halfway house’ with E-Cycles from 14 years, which they also cover, many with disc brakes and front suspension, where they can experience weight transfer and the front suspension compressing when braking.

Motorcycles and cycles could be part of the National Curriculum, within Physics, centre of mass, friction, tipping, leaning, speed, gyroscopes, kinetic energy, braking distances etc. I think it helps when you have a practical example of the theory.

Regarding the essential difference between cycles and motorbikes, it is simply speed, and mastering throttle control which is straight forward.

What is vital to grasp, and to be taught, is that momentum obeys a ‘Square Law’. So it takes 16 x further to stop from a motorbike’s 60 mph as it does from a bicycle’s 15 mph.

The major danger is young riders jumping on motorcycles of 125cc and above, which can get to 60mph or more, without any training.

Let’s all hope that the message gets across.

https://www.bikeability.org.uk/about/

(From Biral, Francesco & Lot, Roberto from 2009)

So what does it mean for riders?

The ‘Fox’s Ears’

It means that you can accelerate the hardest at 45 degrees of lean, which seems odd, but have to roll back the throttle as your lean angle decreases and the front of the machine starts to lift.

Riders need to be acutely aware of the dangers of ‘High Siding’.

The ‘Fox’s Nose’.

This also shows a rider can brake (briefly) at up to 1.5g when upright(ish). This is twice as hard as the Highway Code standard.

This is probably from top speed due to the drag on the rider and bike preventing it flipping over. 1g tips most bikes at lower speeds. You can also briefly brake harder as energy is dissipated rotating the bike during weight transfer.

The ‘Fox’s Jaw’

The ‘jaw’ show a linear relationship between lean angle and braking, up to the extremities of banking – red lines. So track riders can brake deep into corners using the front brake, gradually releasing it proportionally as the lean angle increases.

Riders need to be aware that grip levels on the road can vary considerably, and the dangers of a front wheel ‘wash out’ and ‘Low Siding’.

The DVSA advice, which should be taken, is for road riders to complete their braking before corners, and only use the rear brake in an emergency. Applying the front brake mid corner, as opposed to carrying it into the corner, flips the machine up. This will make it run wide, potentially through the scenery or into oncoming traffic.

However, with training and practice, road riders can be trained to carry the front brake into corners in an emergency, which can be a life saver. But braking into corners routinely just significantly diminishes your safety margin, and likely increases impact speeds.

It’s not sensible to ride on the road anywhere near the limits of grip. However, on a track, it’s necessary, with care, for fast lap times. You need to know where the limits are.

We tried applying the standard traction circle maths to motorcycles in 2015, looking to see what traction should be available for braking as the lean angle increased.

If you use Mohr’s Circle, you get what we called the ‘Cats Claw’ which is the shape of the calculated additional area of grip.

It didn’t look right, and showed far more grip when banked than was available in practice. The question was why?

We looked at Cossalters ‘Motorcycle Dynamics’ which shows an oval, which looked better, but not perfect. 1g on one axis for braking and accelerating, 1.6 g for the other when banked.

There was a recent post on LinkedIn from Mikko Bartolossi, a MotoGP Engineer, introducing a paper from Biral, Francesco & Lot, Roberto from 2009, showing an alternative traction circle for motorcycles.

https://www.researchgate.net/publication/267715875_An_interpretative_model_of_g-

It looks like a fox’s face!

The diagram shows the lateral and tangential g force acting on a motorcycle when cornering, and either braking or accelerating at the same time.

The left and right hand areas show the g force acting on the machine when it is banked. The braking force is shown on the lower half, and accelerating on the top half of the diagram.

The tip of the ‘fox’s nose’ shows that a rider can momentarily brake at around 1.5 g as long as the machine is nearly upright. This will be very briefly as the bike will flip forward otherwise, and is probably from top speed relying on wind drag to stop the bike from tipping fotwards. But shows how a high level of skill can reduce stopping distances. Most motorcycles will flip forward at 1g. (For E-Scooters it’s only 0.4 g). The Highway Code assumes 0.67g.

Riders need to be aware of the dangers of snatching the front brake and skidding and falling, or on machines without ABS. Also somersaulting, when can also occur with earlier ABS systems without pitch control

The red lines at the bottom show a linear relationship between lean angle and the maximum braking force that can be applied, when you’d probably expect the grip to diminish exponentially as the lean angle increases (Cat’s Claw).

This will be using mainly the front brake, as the rear brake will have little effect due to the weight transfer forwards, making a rear wheel skid very likely.

But what is even more interesting, are the ‘fox’s ears’. Accelerating on a motorcycle is limited to 0.9g not by tyre grip, but because the machine will flip over. This time backwards, not forwards as in hard braking.

It shows that motorcycles can be accelerated harder when banked, the peak shown at 45 degrees of lean. Why is this? It’s probably because the centre of mass is lower and to the inside of the corner, and the front of the machine is held down partly by the centrifugal force. The weight is transferred to the rear tyre from the front tyre at the same time, giving more grip at the rear.

This is where racers can gain an advantage, but for trackday and road riders this is where ‘Highsides’ happen. The rear tyre loses grip, slides sideways, then grips again when the rider instinctively snaps the throttle shut in response. The rider is usually thrown up into the air, often over the top of the machine.

We know traction control will not necessarily prevent this. It’s too quick and too brutal. However, modern bikes with Inertial Measurement Unit (IMU) are better and can sense tbe limit aporoaching.

Modern MotoGP and WSBK bikes have traction control, (BSB bikes don’t) so it very rarely happens now in world racing, but many older road going sports bikes also don’t.

This makes older sportsbikes quite difficult to ride safely, particularly as grip levels on the road, as opposed to a track, can vary considerably. There are also two generations of traction control for road bikes, the latest being IMU’s are ‘lean sensitive’ which makes them more effective and safer.

We know from experience at ‘The School’, that riders can still lose traction by accelerating too hard at extreme lean angles., even with traction control. However, the newer systems seems to prevent ‘high sides’ (so far), with the bike ‘low siding’ and the rider just slipping off the side of the machine.

The new Yamaha R9 and other top end bikes now have 6-axis IMUs (Inertial Management Unit) which makes them ‘lean sensitive’, so should be safer in this respect, although the Laws of Physics will eventually intervene at the extremes.

So a 10-year mystery solved, it’s not a ‘Cat’s Claw’, it’s a ‘Fox’s Face’.

Were now working with Prof Owen Williams on a 660 Aprilia fitted wirh a 9-Axis IMU. Next step?

Mike Abbott, British Superbike School

17th June 2025

Updated 16.8.25

Tag: safety