‘Cats Claw’ Theory – Motorcycle tyre grip

We’ve been working on this for a while at The School, trying to show riders the amount of grip available when cornering, in a simplified straightforward way. Many thanks to Martin Knox for the concept.

It must be stressed that this is the theoretical maximum amount of grip available when cornering, dependent on lean angle, on a flat consistent surface, for an expert rider.grip-final-plus-logo

This illustration combines the radial (centrifugal) forces from John Bradleys work, with Mohr’s Circle for the relationship between radial and tangential forces.

The dark green area shows the further you lean, the less cornering grip is left.

The light green areas shows the available tangential grip at angles of lean which is used in braking, accelerating or steering.

Both start to drop off rapidly after 45 degrees of lean.

So at 45 degrees of lean you have in theory 45% of your maximum radial grip left for cornering, (which seems reasonable), and 80% tangential grip for braking and steering (which doesn’t). In practise there is significantly less tangential grip apparently available, particularly when braking, although we know there is enough grip to wheelie a bike out of a corner at 45 degrees of lean.

We got a literal ‘thumbs up’ from Vittorre Cossalter (Motorcycle Dynamics)

We’ve worked backwards, assuming the maximum lean angle is 60 degrees (zero grip), which is only available on a dry race track with soft race rubber.

To stress again this is theoretical, assumes ‘steady state’ on a race track with slicks, ignores the effects of bumps and dips, variations in road surface etc. or extra loads due to sudden steering, braking or accelerating which all need to be smoother the nearer you get to the limit to avoid going over the edge.

You need also to consider weight transfer and tyre slip – which we will discuss later.


Covid-19 Update

In light of recent developments in the COVID-19 crisis, and following the address to the nation by the Prime Minister on the evening of 23rd March, the Auto-Cycle Union has today extended its suspension of all organising permits for motorcycle events until at least 31st May but will be constantly reviewed.
This move provides clear guidance to event organisers, clubs, venues, competitors, officials of the role that the Auto-Cycle Union must play in supporting the broader UK public health agenda.
Auto-Cycle Union Chairman, Roy Humphrey explained, “The government have required that we effectively lock-down for a period of three weeks, however given that the most vulnerable in our society are required to isolate for three months, we feel it only sensible to propose a longer suspension for all motorcycle sport. This is a time of national unity and we need to come together with the broader public community to do all we can to support this battle and ultimately save lives.
This evening, Health Secretary, Matt Hancock said the Government is launching a new scheme to recruit 250,000 volunteers to support the NHS through the coronavirus pandemic. A quarter of a million volunteers, people in good health to help the NHS, for shopping, for the delivery of medicines and to support those who are shielding to protect their own health. We may not be involved in any sporting activities, but, we could help support the NHS through this pandemic!” More information can be found here – https://www.goodsamapp.org/NHS
Auto-Cycle Union will continue to monitor the prevailing advice from the UK Government in respect of the COVID-19 international pandemic and will update the motorcycle community accordingly.
MSVR and MCRCB Updates – http://www.britishsuperbike.com/news/statement-from-msvr-regarding-covid-19-and-the-2020-bennetts-british-superbike-championship-march-24-update/

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We are cancelling the 30th April, 28th May and 25th June dates at the request of the Auto Cycle Union who are our governing body.

All road racing is currently cancelled, including the TT in early June.

We are required to have two ambulances with paramedics in attendance on every date, although in 8 years they have never been used.

We had worked out how to deliver the training at the required ‘social distance’, by using the large covered building on site that used to be a grain store, but clearly the NHS will, if the predictions are correct, need every single trained worker and more.

We are currently still planning to run on 25th June, as there is also the scenario that containment fails and the peak is past, but will be reviewing the situation regularly.

We intend to cancel any event a minimum of a month in advance to avoid messing riders about, and will move existing bookings where we cannot run that date.




A free training day for a young rider on 25th July 2019

We are offering a free training day for a young rider aged 15-17 on 25th July 2019, which includes use of a new Yamaha R3, helmet, leathers, gloves and boots courtesy of Yamaha’s Partner Track Bike Hire UK.

2017_YZF-R3_DPBMC_AU_ACT_004_1280x960 (1)

Entrants are simply asked to send in an email to mike@britishsuperbikeschool.co.uk with their name, age and contact details, answering  this question ‘What is the official prime cause of motorcycle road accidents‘? Personal information will not be used for marketing purposes.

Permission is required from parent or guardian who must attend all day – 8 am to 5.00 pm.

The young rider will attend our usual rider’s course with the older riders, but will be assigned a personal track coach who will be with the rider on track to try and make the day as safe as we can.

The track we use is Blyton Park owned by Ginetta, which was purpose built in 2010 and is safer than most of the old tracks having little Armco, no gravel traps and tarmac run offs almost everywhere.

The track is marshalled by Blyton and our own coaches, with two teams of paramedics and a fire truck in attendance, to try and make the days as safe as we reasonably can, but like every other high speed motorsport there are obvious physical risks.

Get you knee down in safety, in private.

I was mucking about in the garage last year working on the feasibility of setting up a rig to help riders with their positioning on the bike. Many want to get their knee down and are leaning far enough to do it, but don’t seem to be able to get into the right position when they are on track, even after we go through it with them in the paddock.

I’ve just found the photo of a lash up I put together in the garage at home, which anybody could do. Please read carefully below before you try and do the same.:-

Leaning rig

The idea was to bring the track up to the rider on both sides, so they could play around with their position on the bike, and practise moving from side to side getting used to where they should be. It is quite painful when you start as you’ll likely use muscles you haven’t used before.

The first problem is to secure the bike properly – which a normal rear paddock stand will not do – you’ll drop it in the garage which can be embarassing and painful. I used a stand with a rod though the rear axle, and then tie wrapped an aluminium tube across the back and wedged it. You might get away with tie wrapping normal padddock stand arms to your swing arm spools, but make sure it is stable before you do anything else and the stand is braced from left to right.

I used a sheet of 8′ x 4′ polystyrene I had lying around, cut in half to represent the track, but anything around 4 foot square and flat would do – chipboard etc.

I then wedged the sheets with a couple more paddock stands at 45 degrees to the bike, lining them up with the tyres at the bottom.

If you then sit on the bike (making sure its stable and won’t fall over when you hang off) you can fairly quickly work out where your body needs to be to get your knee down – and it’s far better than looking down when you are riding trying to see how far you are away – as some riders seem to try.

You will find you need to move your upper body across as well as your backside, and keep your pelvis at right angles to the bike, and put the ball of your inside foot on the peg.

You will hopefully find a position that feels comfortable and safe with you firmly wedged in place – usually with your outside arm against the petrol tank. You can then practise moving to and fro from your normal riding position and to the other side. If you practise this it should become second nature and will help you get those new muscles working. Next time on the track it should feel natural and comfortable.

I doubt whether this is a unique riding aid – just that they are usually hidden behind locked garage doors.

Hope this helps. Take care.

Feedback appreciated.


Mike Abbott ACU Coach #61220

British Superbike School.





How to avoid a Fatal Road Accident – drive into the vehicle in front!

Firstly most accidents (now called collisions or RTC’s) are mainly caused by road users not paying attention, with the exception of motorcycles >500cc where ‘loss of control’  is the main cause.

Many collisions are beyond an individual road user’s control, but there are actions we can take – if we are prepared – that maximise our chances of survival or minimise the risk of life changing injuries.

On (or rather off) a motorcycle it is ‘how you fall’ and crucially ‘what you hit‘ which determines the outcome – (see the late Dr John Hind’s last video). However ‘What you hit’ is an issue for all road users.

For anybody on two wheels, road furniture represents a very real unique danger, increasing your chances of dying by no less than 17 times, according to the World Health organisation. So you need at all times not only to be aware of other vehicles and the danger in particular of trucks, but also anything by the side of the road, including trees which are also potentially fatal to any road user.

Target fixation leads you to ride or drive into what you are seeking to avoid, so you need to look where you want to go, not where you don’t. Getting into routinely scanning and looking ahead helps you both plan your ride, and identify potential escape routes.

This full list of factors is called ‘Haddon’s Matrix’, but here we are just considering ‘The Event’, and its related ‘Agent‘ and ‘Environment‘, as we can’t change anything else when a collision is immediately likely, and environmental factors are what we are seeking to address.

Haddon's Matrix

We have to avoid rapid de-acceleration as up to 56 g’s is all that is surviveable, and we are surprisingly fragile. Although, according to the TRL, in a car we usually survive front and rear impacts from 30 mph, (but not from 40 mph), a side on impact can kill at < 20mph due to a lack of crumple zones. Clearly the situation is even worst when you come off a motorcycle or cycle where even 15 mph can be fatal if you hit something solid.

Also the nature of impacts are not usually always obvious. The impact and rate of de-acceleration is the delta (difference) between pre and post collision speed. If you run into another parked car of similar weight in your car, the impact is circa half the speed as the stationary vehicle will move, reducing a 60 mph impact into approximately 30 mph delta. One car at 60 mph = two cars at 30 mph (approx – as kinetic energy is 1.5 x mass x speed squared). This, although it seems a considerable impact, is probably survivable particularly due to front and rear crumple zones.

Riders and bikes are two separate masses – riders have only flesh and blood crumple zones – so none of the above really applies. Your personal weight will have minimal effect, so this is not an excuse to eat more pies. But in a prospective shunt from behind, on your bike you can maximise your chances by being either positioned to the right or left hand side of your lane and the vehicle in front, so the vehicle coming up behind could miss you, and you could also potentially move past the vehicle in front, and out of the way. Get in the habit when you stop at the back of a queue, to watch behind until the vehicle pulls up and acts as a shield.

Riding (or even driving) into the back of a 40 tonne truck at 40 mph would be close to a 40 mph delta and not likely survivable – so even for cars it is can be ‘what you hit’. Modern 4×4’s are safer due primarily to their weight – run into one of those at 2 tonne in your small car at 60 mph and your impact is nearer 40 mph – probably not survivable – their’s would be 20 mph and not significantly life threatening.

So if you are in your car at the tail end of a jam and you see a car behind that is not going to stop in time, you need to consider standing on the brakes or better still bizarrely drive into the car in front then brake! You have just doubled your mass and potentially in theory halved the impact – although you potentially put the occupants in the car behind in significantly greater danger. You still could also be crushed if your car’s shell deforms too much.

Would you have the presence of mind and time to spot potential collisions ahead of time and act appropriately – or are you just going to find you’ve suddenly sprouted wings? Or alternatively become a Buddhist and wait for another chance?



Review of 2016 Motorcycle Road Accidents – ‘Speed Awareness’ not working

‘Speed Kills’ – A Big Fib

The 2015 National Statistics on road collisions were published recently. Interesting reading.

Speed does not kill. It is only a ‘contributory factor’ in 16% of fatal accidents.

Regarding just fatalities, these are the top causes as reported by the police:-

Loss of Control                                                   32%

Failed to look properly                                   27%

Careless reckless or in a hurry                     20%

Exceeding the speed limit                            16%

Failed to judge others path or speed         14%

Poor turn or manoeuvre                                 14%

Driving too fast (but within limits)             12%


(DoT – RAS50007 2015)

These don’t add up to 100% as there can be more than 1 contributory factor, but clearly in 84% of fatal accidents, speeding was not a factor.

Regarding published trends for all collisions over the past 5 years, ‘loss of control’ has improved slightly probably due to vehicle developments, but ‘failing to look properly’, being ‘careless reckless or in a hurry’, or ‘making a poor turn or manoeuvre’ have all steadily increased. ‘Driving too fast for the conditions’ is stable at 7%, so no change there, and speeding’ for all collisions isn’t even in the top 10. (Table RAS50002).

We are simply not tackling the primary root causes of fatalities.

In response to an inappropriate focus on ‘speed’, many speed limits have been reduced, speed cameras installed costing £ millions all over the country, ‘safety camera’ partnerships abound.

‘Speed Awareness Courses’ arrived.

I was told at the recent Road Safety (AIRSO) Conference that more than half the drivers in the country have now done a Speed Awareness course for minor speed infractions. That’s circa 23 million courses at £90 a go, plus no doubt a healthy profit for the AA who deliver them. Drivers and riders have lost time off work and been fleeced collectively for an estimated £2 billion.

The focus has succeeded in reducing speed I think (as has it appears high fuel prices). Vehicles are noticeably driven in general more slowly than they were, but this seems to had had little to no effect, as it was never the main problem.

Strangely, those who are convicted of driving or riding significantly over the speed limit don’t have the option of a speed awareness course – which is just plain ‘nuts’, as these people clearly are likely to be the major continuing risk. Maybe this is the problem? My course was dominated by confused pensioners (my peer group) many of whom misunderstood how fast they could legally go, so they’ll probably go faster as a result. And we all no doubt spent the next few months looking for speed signs and cameras, as opposed to where we were going.

This is the 5 year rolling average change of KSI (fatalities and serious injuries) to smooth out peaks and troughs from the latest DoT report:-


Serious casualties have been decreasing significantly during the last 35  years, but are now static (marginal %age improvement), with improvement tailing off over the last 5 years. Look at just the fatalities (excluding serious life changing injuries):-


So in the last 5 years fatalities are about the same – very little improvement. The main explanation for any improvement is probably that cars are getting safer with airbags and ever stiffer crash test requirements. This seems to be confirmed as motorcycle fatalities are actually up 8% in 2015. Mile for mile you are now 57 times more likely to be killed on a motorcycle than in a car.

It could be argued that reduction in speeds has also improved the outcomes, and no doubt that is what the ‘speed lobby’ will claim, but there is no evidence that I have seen to support this. And it’s I believe likely to be far more effective tackling the primary causes of fatal collisions, rather than accepting the worsening situation and trying to minimise the impact (no pun intended).

You can’t argue that speed awareness is reducing the impact speed and severity of collisions, as the number of SKI’s is now static.

The blind focus on speeding to tackle fatalities has failed. Speeding related fatalities hit a low of 194 and 12% in 2012, but show an increasing trend, up to 244 and 16% in 2015. The situation is now significantly worse.

We are all very lucky to have world class emergency services who seem to have been steadily improving survival rates, which again may be a significant factor in reducing deaths.

There are also separate figures included this year from the NHS (not the police) and they show deaths and serious injury admissions from road collisions (MAIS3+) have remained largely unchanged for many years.

As the ‘Speed Awareness’ program has clearly failed, there is talk now of ‘zero tolerance’ for speeders, which is very unlikely to help either. The huge damage already done to the relationship with the police will suffer further. Before speed cameras the police applied common sense to speeders, usually only prosecuting when the speeding was dangerous, and lecturing drivers instead. I believe it worked.

12% of fatalities were actually caused by vehicles within the speed limit but still travelling too fast for the conditions.  And this is even after the reduction in speed limits on very many ‘high casualty’ routes, which I suspect has caught many if not most of the speed awareness attendees. There is no consistency in the application of speed limits which look almost random at times. We have some 30 mph dual carriageways and a 60 mph limit on most single track roads. Ridiculous.

22 million drivers and riders have been lectured on the evils of speeding, misled into believing that keeping within the speed limit is the single most important thing to do, and will help to keep them and others safe. What a misleading wasted opportunity of biblical proportions.

40% of fatalities – two and a half times more than the 16% who were speeding – were caused by a failure to look properly or the miss-judgement of another’s path or speed. Twice as many fatalities as speeding (32%) were caused by the driver/rider losing control. 20% were careless, reckless or in a hurry, 14% were making a poor manoeuver, and 13% were either drunk or drugged (Table RAS50007).

(NB The combination of both speed and losing control contribute to less than 1% of collisions).

The opportunity is there on ‘Speed Awareness Courses’ to present a truthful picture of what actually causes collisions and how to avoid them. Primarily we all need to take more care and pay far more attention, avoid distractions, concentrate.  The fact that you end up on a speed awareness course is because you weren’t paying proper attention!

The key factor of ‘reaction times’ is not stressed. TRL research shows reaction times at least double if you’re not paying attention, increasing stopping distances by 30 foot at 30mph, 60 feet at 60mph, and worse case can be 6 times longer if you can’t recognise a hazard for what it is. Drivers and riders also need to be taught properly how to control their vehicles as ‘loss of control’ is the primary cause of twice as many collisions as speeding, despite all the features on modern vehicles.

Standards of driving are noticeably poor. 55% of drivers fail their tests which is appalling (30% of motorcyclists fail) – so many poor drivers inevitably get through by chance eventually, which may also be a major factor. Training in general needs totally revamping to make it more effective. Vehicle control needs to be taught properly as does such skills as overtaking and driving on a motorway which amazingly are not covered.

There are doubtless often early warnings via minor collisions by which the insurance industry could identify those who need further training, before probably an inevitable ‘big one’.

We need to abandon the very misleading ‘Speed Kills’ strap line, focus on the need to pay attention, train road users properly and significantly increase the levels of traffic policing as RoSPA have recently proposed. Back to ‘Think’?

A new course is needed on ‘Collision Avoidance’ based on data and solid theory, not hysteria, on the cause of collisions, the dangers of losing control and how that can be avoided, and the importance of always paying attention stressed. This could be applied primarily to drivers and riders who have collisions and serious offenders, not marginal speeders who present at best a very low risk.

We have collectively allowed ourselves to be hijacked by the anti-speed lobby and misleading populist newspaper stories, and the Government taking an ineffective soft self-funded option rather than dealing properly with the root causes of road fatalities.

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