Against the flow

[faffi]

Having just re-read the "Lowering the body" topicI am going to present a few statements that will go against popular belief. Fortunately, I have not much scientific knowledge or evidence to support my statements, so there will be plenty of chances to debate against me. Still, I think I am right  

Let me start with a few examples:

Mike Hailwood never did hang off in any way, but had superior cornering speed.

Mick Doohan leaned out with his torso and hung his butt off to the inside, fully crossed up - the bike was leaning, his body hardly at all. He won tons of races and championships.

Back in the 1960s, riders lapped IoM at over 100 mph on barely modified street bikes with little horsepower, little cornering clearance, poor brakes and even worse tyres. And to top it off the roads were in much worse condition than now. Only a few per cent of all riders in the world could go that fast on a BMW S1000RR today.

In the late 1980s, a Performance Bikes test rider decked out the FZR750RR enough to lift the tyres and crash. He was hanging off. Another test rider previously went around the same corner at a higher speed, barely hanging off, nothing scraping.

 

So, to my claims:

1. Hanging off makes only a small difference in how far the bike must lean for any given cornering speed (this has been proved by MOTORRAD and others)
2. Hanging off has no impact on safety
3. Leaning out has no impact on safety
4. Proper steering techniques is the primary tool need to go fast and is little impacted by rider positioning
5. Only when you are looking for the last percentile does hanging off bring much of value

 

Why do I believe this? Simply by observation and personal experience. How can a Superbike rider on slick tyres in pouring rain, bike almost upright through the corners, short-shifting to avoid spinning up, still circulate faster around a track than most street riders doing a track day in the dry, despite the latter dragging knees, braking hard and using a lot of revs and throttle? It can only come from the way the pros change direction and the lines they take. Same with the riders of the 50s and 60s - take a look at old movies, and they barely lean off vertical, never hanging off. But they sure lapped rapidly! In 1999, with both legs shot, having to be lifted onto the bike and get help pulling the clutch due to a damaged hand, riding for the first time in months after his career-ending crash, on a bike set-up for Criville and with the engine tune changed since Doohan last rode, not knowing the tyres, not being able to do much with his body from injuries - and on the second lap Mick was only 4 seconds off pole, just cruising around. Finally, look at a motoGP rider playing around, wheelying, barely hanging off, just having fun - and still riding within 10 seconds of the lap record. 

Clearly, there are things far more important than body position going on. Instead, I believe that using "proper" body positioning can help many riders into steering correctly. So it's not the body position that allow the bike to corner a lot faster, and they are not magically gaining acres of cornering clearance due to hanging off, but the rider may now being able to do the right things. Sit still on the bike and do the very same steering, and corner speed will be similar. Chicken strip widths as well, as hanging off alone only gain you 2-3 degrees.

Finally, my own experiences. I tend to use relatively much lean, but it depend on the bike I'm riding. I recently rode a KTM 950 Super Enduro, and barely had to lean in order to keep a decent cornering speed. Same, strangely, with an old Z1 I recently rode - the chicken strips on the narrow tyres are immense, but cornering speed is pretty respectable. With my current FZ-07, I have no chicken strips on the rear tyre and just a hint on the front, but I do no go much faster. I cannot tell why. I sit upright most of the time. If I can see far ahead, I may lean my torso a little inwards. If visibility is poor, I hang out - or sit crossed up, as you say - in order to see further around the corner. Never have any of this caused me any grip issues. Perhaps I'm lacking experience - I've only been riding since 1980. Maybe the bike will bite me one day for my stupidity.

So why do people lose the rear or the front and crash when they sit "wrong"? Either because they give the bike the wrong steering inputs or use either throttle or brakes wrong. Or all of them. The bike does not care how the weight is placed, just what that weight is doing, ie what moments/forces it sends through the bike.

 

So there you have it, long rant over  I honestly believe, had he lived and been in his prime today, Hailwood would have wiped the floor with all of you if you were all riding let's say BMW S1000RR with all gadgets turned off, you hanging off trying to play Marques, Mike sitting classically upright. Hotfoot being the possible exception. Could he have gone slightly faster if he learned to hang off properly? Sure. But his way of controlling the bike would be more important than what you gain by hanging off.

 

 

[Hotfoot]

I agree that (a) choice of lines and good control of the bike are more important than body position and (b) riders can crash due to poor body position because of improper/uncontrolled bike inputs, like unwanted bar pressure.

But here is a question for you - if you are going as fast as you can go, and trying to catch a faster rider, and you run out of ground clearance (dragging a peg, or your exhaust, for example) what you would change to try to go faster to catch that other rider?

[playersnoopy]

1 hour ago, faffi said:

So, to my claims:

1. Hanging off makes only a small difference in how far the bike must lean for any given cornering speed (this has been proved by MOTORRAD and others)
2. Hanging off has no impact on safety
3. Leaning out has no impact on safety
4. Proper steering techniques is the primary tool need to go fast and is little impacted by rider positioning
5. Only when you are looking for the last percentile does hanging off bring much of value

 

 

1.  Need to understand how bikes turn to know that you're right hanging off doesn't make a difference; the steering and lean affects how a bike turns.  But there seems to be a misconception on why we "need" to hang off the bike and some assume it's to cause "less" lean angle rather than to offset the balance to "keep" the bike in its turn.  I'll cover the science of it later as it is a lot of info -.-  But in short more lean angle the less steering angle for the same radius of turn needed; this is the most important factor to understand.  Which is why you can always turn a bike by counterweighting; but this is a little harder for sportbikes than say dirt bikes or flat track riders who in fact counterweight to lean the bike.  When hanging off in a turn you can let off the handlebars (a little and safely) and see the bike maintain its lean throughout the turn.  Take a rider off the bike for analysis (watch youtube videos of idiots falling off their bikes doing wheelies and the bike remains upright but coutersteers by itself back and forth; due to Newtonian laws) and we see that the bike would countersteer back to the opposite if we don't apply additional forces to prevent it.

2.  This is subjective; but for sportbikes you can only counterweight so far before the bike will just fall to the ground unless you're going fast enough where the centripetal force keeps you up.  You can also lean into the turns upright and lean with the bike as most DMV manuals says to do when at speed.  But now the topple over effect is again raised because you essentially become a tall lever; and the greater the distance of the lever from the fulcrum the less force required to torque the lever.  So basically easier to topple over plus it's harder to balance yourself upright for continuous turns on sportbikes.  Hanging off brings your Center of Mass/Center of Gravity (CM/CG) both same in this case lower and makes the bike more balanced in the turn.

3.  Similar to 2 when talking about dirt bikes or lighter bikes counterweighting is easy; bring a 400lbs bike into play it's very hard to balance the weight when you weigh half the bike or less.

4.  Proper steering techniques steers the bike; position comes into play depending on how fast you go.  Try counterweighting at 80mph on a sports bike -.-

5.  Should be self explanatory if you accept response to 1

[Jaybird180]

@faffi I'm interested in the MOTORRAD proof you cite please.

[faffi]

12 hours ago, Hotfoot said:

 

But here is a question for you - if you are going as fast as you can go, and trying to catch a faster rider, and you run out of ground clearance (dragging a peg, or your exhaust, for example) what you would change to try to go faster to catch that other rider?

As I mentioned, hanging off is useful if you are going really fast because it will give you 2-3 degrees extra "lean" (more cornering speed), but I also believe that hanging off brings far less than being able to steer correctly. Combine the two, as you must to win races at the top level, and you will go as fast as you can

[faffi]

6 hours ago, Jaybird180 said:

@faffi I'm interested in the MOTORRAD proof you cite please.

I have posted it twice already, but here we go again  

 

[Lnewqban]

7 hours ago, faffi said:

............. but I also believe that hanging off brings far less than being able to steer correctly........

I believe that correct steering and hanging off are not related at all.  It is more possible to introduce incorrect steering and throttle inputs while hanging the body off if not properly locked to the tank, seat and pegs.

Going back to your first post: In the last century, we used to race without hanging off and that worked.  I don't know about old bikes and riders being as fast as equivalent machines and racers of nowadays; it would be an interesting thing to watch if old conditions could be reproduced.

How some things evolved: Engines went from light and explosive (2-stroke) to heavy and docile (4-stroke).  Tires went from rigid/marginal grip (bias-ply) to pliable/super-grip (radial).  Those two factors widen the profile of the tires, resulting in increased lean angles of the chassis for similar speeds and curves.

At the same time, better surface of tracks and softer rubber compounds increased possible maximum grip, traction or coefficient of friction. Those two factors permitted harder cornering (more speed and tighter radius of turn), which resulted in extreme lean angles of the chassis of the bike (around 60 degrees).

Bottom line: racing bikes can now lean beyond the dimensional limits of dragging parts.  Hence, there is some room to increase speed around a turn if the chassis could be pushed away from the racer and a few degrees upright.

Why to hang off for less dramatic and extreme corners if chassis parts are not dragging yet?  Better suspension, which translates into more consistent traction, is the answer.  The imperfections of the track induce vertical movements of the bike, but the strokes of the suspension are diagonal while the chassis is leaned (there is a useful stroke and a wasted one) and the combined forces of gravity and circular trajectory (some call it centrifugal, some centripetal, some g-forces) increase the load on the springs (as much as double the normal weight of bike and rider at 45-degree lean).

Regarding the historical styles of hanging off:

http://forums.superbikeschool.com/index.php?/topic/1362-knuckle-to-knee—dragging/

 

[faffi]

I am not actually dissing hanging off - it will make it possible to corner a bit faster. It will not gain you many seconds per lap, but it will gain maybe 2-3 on average for a top rank rider (me speculating here). Of course, even if it's just a tenth it's worth while.

However, I think there are far more important aspects for riders to learn than hanging off. If someone goes faster than before with considerable less lean when the rider start hanging off, it does not (me making a statement) have nearly as much to do with the riding position as with the rider having improved other things (see MOTORRAD figures for what hanging off brings).

Also, for street riding, hanging off has disadvantages that, for me at least, outweigh any benefit of leaning a bit less; it is tiring, it usually means you cannot see as far around a corner, and it can make it harder to change direction for something unexpected. But I'm sure there are those finding it worth while.

Anyway, it all boil down to this; I believe hanging off is credited for more than it can actually deliver. It is no doubt an important tool for the expert rider, but again I think there are a lot of things that can help much more when it comes to riding safe and fast.

Here's a video of Mike Hailwood racing a Ducati. It's fun to watch him going quicker through the esses, despite having a chopperesque amount of wheelbase, rake and trail. The Ducati also made substantially less power than the Kawasaki and Honda that came 2nd and 3rd. It would be very interesting to hear what the coaches think is the main reason why Mike goes that quick compared to the competition, as I do not have a clue.

 

 

[Lnewqban]

I fully agree with you, faffi.

Reason may be that it is easier to mimic performance riders "looks" than mastering other things that are less evident.  Knee down seems to be the highest goal for many riders.  Whoever feels the need to hang-off while street riding is speeding big time.

What a pass at 11:15 of that vid! 

On his own words (copied from http://www.mikethebike.com/quotes.htm):

The former editor of a magazine asked him: "What do you do to the others in order to beat them apart from outride them?"
His response was: "Look at all of them on the front grid before the start. You can see it in their eyes. If they think they can beat you, smile, give a nod and a wink. It works every time. Then you go out and show them what you meant."

Sadly, he died 35 years ago.

 

 

[Jaybird180]

On 7/22/2017 at 6:02 AM, faffi said:

I have posted it twice already, but here we go again  

 

I saw the summary you posted; I need more to make heads / tails of it. I have been on my phone trying to translate it - seems I need a desktop, otherwise I'll need to download an extension.

[Jaybird180]

Mike Hailwood died in a traffic accident. Recently, Nicky Hayden was also lost in a traffic accident.

We've all heard the saying, "live by the sword, die by the sword." In Western culture it's considered a warning, whereas in Martial culture it's considered an honor.

Regardless to which assignment one gives to the loss of Mike and Nicky, both are tragedies.

[Jaybird180]

I don't know how much hanging off helps, my quick estimation from my Physics training says it does; I'm inclined to go with @faffi in that there's a bit of placebo effect happening. I wished that I could read the MOTORRAD in full.

The rider is the most important element of the whole thing and his psychological and mental state is affected by many things. My experience is that it helps me with vision skills. I am not sure why, I have just observed that it does. That alone (IMO) is a major building block and obstacle to quick, safe riding.

In the KC article linked above, he polled riders with 2 questions: what result do you want and what do you want to feel; questions that very well could yield different answers- genius.

I don't know if we could empirically answer the question as to how much of an effect hanging off has- someone would have to write simulation software to run comparative analysis, a monumental feat considering that all the mathematics on single track vehicles has yet to have been worked out.

I think however it could be very worthwhile to propose a robotics experiment to a university;  there's an annual competition, the name of which escapes me at the moment. Honda also does motorcycle-robotics experimentation; I know we can resolve a lot of things with either approach because the man-in-the-middle will taint the search for understanding the pure science of it.

[Jaybird180]

I have the people and resources at my access- there's nothing preventing me from seeing if I can get some interest from the scientific community at my access. I will pitch it tomorrow.

[faffi]

I have translated it - let me know if it is OK to read, or I can share a link to my document for those interested.

 

Who leans that far? Where are the limits? And what are the differences between street bikes? We compare bikes around a skid pad: Supermoto, Naked Bike, Cruiser und Superbike. We have also discused with experts and tried qualifying tyres from WSBK to see how they differ from street legal sport tyres.

Why do we lean?

Without lean to counter the centrifugal forces, the bikes would simply fall over. Leaning against the forces the correct amount keeps the machine and rider in balance. For a given radius, the faster one rides, the more one must lean. Or for a given speed, the smaller the radius, the more one must lean.

How far can we lean?

Sport bikes are generally limited by grip, or friction. With good tyres on a good road we typically have a friction quotient of one µ.

This means we can theoretically lean 45 degrees. If you lean further, or you try to slow down or accelerate, you will slide. However, we know it is possible to achieve greater angles of lean. How? Because very grippy tyres and a grainy road surface can interact like gears. That’s why in MotoP and WSBK we can now see bike lean angles as high as 62 degrees. With the rider hanging off we can even see combined lean angles beyond that. What is that- different lean values?

Corner master Jorge Lorenzo show us the difference between bike lean and the third lean.

Lean angle isn’t always lean angle

Basically, we talk about three lean angles. The first one is the effective lean angle. This is a theoretical value and is calculated from the speed and the radius of the corner. This counts for every bike and every rider. But this theoretical value for effective lean angle is based upon infinitely narrow tyres. Now to reality. Imagine watching a vertical bike from behind. Pull a vertical line through the bike’s centre line, the tyre and to the ground. This is where the contact point is as well as the CoG. Now place the bike on its kickstand. Now we see that the contact point between tyre and road has moved to the side somewhat because the tyres are not infinitely narrow. The more we lean the bike, the further away we move the contact point away from the bike’s centre line. If we draw a line through the CoG and both the centre line as well as down to the contact patch, we create a triangle. The angle between them is the second lean. This is the added lean required to corner at the same speed as you would have been with infinitely narrow tyres. This also show that wider tyres require more lean narrower tyres.

Lorenzo shows us the difference between the bike’s lean and the third lean. With his extreme hanging off the rider is leaned over far more than the bike. The combination of the two - bike and rider - gives the third angle of lean, the combined lean. Bei 62 degree bike lean we can get to an extreme combined value of 66 degrees.

What can production bikes muster?

We take 4 different bikes and try them on the skid pad sitting in line with the bike, pushing the bike down and hanging off. We then measure bike lean, calculate combined lean and measure cornering speed. What gives the greatest speed?

Lean angle with the Husqvarna 701

The skid pad has a diameter of 55 metres. Upright lean is 47 degrees, speed 57 kph. In typical sumo-style, pushing the bike down while leaning out, we managed 57 degrees bike lean and a speed of 62 kph. The combined lean is 51 degrees. This is the biggest difference in the test (6 degrees), a result of a light bike, high CoG, high and wide bars, narrow seat, low set pegs.

Final attempt is hanging off, and we get the exact same values of 62 kph and 51 degrees combined lean. The bike is only leaning 46 degrees. So the speed is the same, but pushing the bike down sumo-style bring some advantages; more bike control and easier to catch slides being the predominant.

Ducati Diavel, Cruiser & Co.

Unlike for sport bikes, cruisers are limited by dragging parts when it comes to possible lean angles. With 41 degrees, the pegs are in contact with the asphalt. This will be the same regardless of what style is used. This gives us a fantastic opportunity to compare cornering speeds between the various riding styles. Sitting up gives 50 kph, pushing down 47 kph and hanging off 53 kph.

MotoGP bikes can actually accelerate harder when leaned over than in a straight line. While maximum acceleration on level ground is limited to about 1g, a MotoGP bike can accelerate at 1.2g when leaned over 45 degrees! For street bikes on public roads, 45 degrees means zeron grip left for acceleration. A modern street legal sport bike outfitted with racing tyre and circulating on a grippy race track can give up to 1g of acceleration when leaned over at 40 degrees.

Cornering with the Honda Fireblade

First we ride on the stock Bridgestone S20 “G” tyres. Hanging off gives 61 kph and 48 degrees of lean for the bike, combined 51 degrees.

What difference does qualifying tyres make?

WSBK Q-tyre, straight from the heaters, has tremendous grip and feedback. We do not give up until the Fireblade gets “floaty”, a sign we are nearing the limit. With the bike leaned over 53 degrees we reached 65 kph. Combined lean is 55 degrees with the rider hanging off. Why not faster? The asphalt was cold (less than 10C / 50F) and the asphalt not overly grippy. Add a slight negative camber and the limits were like that. But this was the same for all tyres. The problem for the Q-rubber was that they lost their heat rapidly, losing grip in the process.

A Pirelli-technician explained that the racers don’t lean further on Qs, but they have more grip available for braking and acceleration. Enough to give about a second lower lap times. Two laps, though, and they are mostly gone.

Cornering with the BMW S 1000 R

Standard Pirelli Diablo Rosso Corsa allowed 59 km/h when hanging off, with 47 degree bike lean and 50 Grad combined lean was good, but better results were limited by grinding foot peg feelers and gear shift lever.

Foto: www.factstudio.de

Husqvarna Supermoto 701

Sitting straight made the rider feel uneasy, which limited lean and cornering speed.

Foto: www.factstudio.de

The Sumo-Stil made the rider feel at most comfortable. Sliding tyres and grinding parts set the limit.

Foto: www.factstudio.de

If the rider had been able to hang as well off as he was at pushing the bike down, he could have cornered faster.

Foto: Archiv

Tyre width and CoG

Wider tyres demand more lean for any given corner speed. The same goes for lower CoG. The difference between the tall Husky 701 with relatively narrow tyres and the low Diavel with its ultra-wide tyres was 3 degrees when doing 50 kph around the skid pad; 38 for the 701 and 41 for the Diavel.

Foto: 2snap

 

Lateral acceleration and lean

While 45 degrees of lean gives 1g, 60 degrees give 1.7g, which isn’t the same as going 1.7 times faster by any means.

Foto: www.factstudio.de

Ducati Diavel

A good way to see what the different riding styles can bring.

Foto: www.factstudio.de

Looks weird, feels weird.

Foto: www.factstudio.de

Feels much better than pushing the bike down!Foto: Archiv

Der Kammsche Kreis

This shows how much grip is left to brake or accelerate or steer at various lean angles. If you are leaned over to use half the lateral acceleration, you have 85% grip left to other forces (green arrow).

The red arrow indicate that you have only 10% grip left to do anything else than circulate.

Grip through the gear effect.

Mikrorauigkeit (red) [micro coarseness], with spikes between 0,001 and 0,1 Millimeter is especially useful in the wet, while Makrorauigkeit (green) [macro coarseness] between 0,1 und 10 Millimeter make the difference on dry roads.

Foto: Archiv

Contact patch with a 180/55 sport tyre with a racing profile at 48 degrees of lean. 38 square centimetres contact area. Typical contact patch is that of a credit card.

Public roads are more slippery than tracks, particularly in the wet because the surface lack Microraugkeit.

Cold rubber, especially with sport tyres, can cause the tyre to slide on top of the asphalt instead of forming around it. Hence sport rubber is worse than touring rubber below a certain tyre temperature.

Karussell around Nürburgring is bumpy and can be taken with 58 degrees of lean. However, thanks to the sloping surface, the angle between the road and machine is just 33 degrees.

Lean and speed

The Fireblade on WSBK Q-tyres managed 55 degrees of lean and 65 kph. If we theoretically put Marquez on the same skidpad with a combined lean of 66 degrees, he would have circulated at 78 kph.

 

[jcw]

Like stated above, if you run out of lean angle and drag hard parts, hanging off obviously helps.

Short of that, hanging off might give you a small margin or error to add lean/countersteer if you can't make the corner.

Way short of that, you probably should just be in a position as comfortable as possible to make your throttle and steering inputs. For me thats the traditional inside of midline with your outside leg locked on tank.

[Jaybird180]

I made an attempt to get through the newly translated article, thanks @faffi.

I think their premise of a 3rd or combined lean is flawed. But even if one were to accept it as correct, they didn't follow their math when discussing the Husky as their combined lean was less than their bike lean. I surrendered afterwards.

[Jaybird180]

When you hang off and push the bike up at corner exit getting hard on the gas...some people actually believe they can push the bike up! Maybe you can if you were in your knee the whole time as you'd have something to push against. 

[faffi]

1 hour ago, Jaybird180 said:

I made an attempt to get through the newly translated article, thanks @faffi.

I think their premise of a 3rd or combined lean is flawed. But even if one were to accept it as correct, they didn't follow their math when discussing the Husky as their combined lean was less than their bike lean. I surrendered afterwards.

If that's the case, it's an error of mine. Tried to find it, but couldn't. Rider in line with bike, bike and rider leaned 47 degrees. Bike leaned more than rider, bike 57 degrees, combined 51. Bike leaned less than rider, bike leaned 46 degrees, combined 51.

Since it was late and the story very long, I simplified as much as I could to save myself time. No need for extra prose  But I could no doubt have spent more time perfecting the English if I had been arsed  

[faffi]

1 hour ago, Jaybird180 said:

When you hang off and push the bike up at corner exit getting hard on the gas...some people actually believe they can push the bike up! Maybe you can if you were in your knee the whole time as you'd have something to push against. 

Again, it could be due to poor wording on my part if you took this from the translation. But you can shove the bike more upright if you toss yourself into the corner - the force required to move your body will have a counter-force, and this can only go into to bike. So the bike goes one way and the body the other.

[jcw]

1 hour ago, Jaybird180 said:

When you hang off and push the bike up at corner exit getting hard on the gas...some people actually believe they can push the bike up! Maybe you can if you were in your knee the whole time as you'd have something to push against. 

 

I get the sensation of "pushing" the bike up as a countersteering input coming out of the corner. If you remain in your "hang off" position or even exaggerate it on corner exit with your upper body, you really have no recourse but to countersteer the bike back upright out of the lean. For me that movement of putting bar pressure on the outside hand ( and pulling with the inside hand) could be interpreted as "pushing" a bike up. It's not a subtle sensation. Sometimes you'll have to really "push/pull" to straighten the bike up to get ready for the next corner.

Maybe you are essentially saying this...

[Jaybird180]

8 hours ago, faffi said:

.... it's an error of mine...if I had been arsed 

Are you trying to make fodder for poking fun in English??? LoL

[Jaybird180]

8 hours ago, jcw said:

 

I get the sensation of "pushing" the bike up as a countersteering input coming out of the corner. If you remain in your "hang off" position or even exaggerate it on corner exit with your upper body, you really have no recourse but to countersteer the bike back upright out of the lean. For me that movement of putting bar pressure on the outside hand ( and pulling with the inside hand) could be interpreted as "pushing" a bike up. It's not a subtle sensation. Sometimes you'll have to really "push/pull" to straighten the bike up to get ready for the next corner.

Maybe you are essentially saying this...

I think CSS has a drill on that at the end of L2, something like pull up drill, or pickup...I forget (wink, wink).

[Releeuw46]

Nice discussion about the need to hang off or not. If you can achieve equal laptimes with both techniques, what does it matter which one you use. It will become your personal choice of what you like or not, not a SUM of calculations on angles and forces that should lead to the optimum style for the fastest lap time.

For me I really like to wrestle my GSXR1000 around with some decent physical input from my 6f4 body. Why, because it is fun. The same why my track mate on his Ducati 1098 is acting like a Hailwood replica, and having the same amount of fun. Unless you're doing competition, laptimes become more of a priority. For trackdays riders like me fun comes first, and with it a riding style you feel happy with. 

[Johnno down under]

It's clear to me that a big piece of the puzzle is the bike set up. Some street bikes need almost effort to steer other require a firm hand, and others yet need assertive gymnastics to make them go where you want.

After a decade of pushing a small 400cc fourstroke, Suzuki Impulse around corners at stupid speeds, back in them1990s I had a chance to consider more pricey alternatives. So out for a test ride. Fist a BMW boxer 800cc. Well that was interesting, It really didn't like corners at all. Sure it could change direction, but once turned in it was stuck on line unless brutally steered. Then a Suzuki RF900F. This bike didn't so much love going around corners as ignore the fact that corners might be challenging.  

Having eliminated the boxer, the two very different Suzukis are worthy of discussion. The Impulse turned as smoothly as the rider permits. Full extreme hang off, body vértices bike turning with the front wheel towing the bike into corners after initial countersteer, or suberbike style half cheek locked in sharp countersteer. Or even wild, suspension hammering turf the bike into the corner and hang on style the Impulse with its marginal 1980s cheap street bike suspension would take it all in stride. And cornered fast just like a lightweight ought to.

but then by comparison the RF900f a prices, younger well developed sports tourer made the impulse look like a wanton child. Cornering was smooth, effortless, and stupidly fast. Counter steering -why bother. Hang off - if you really really want to. Lean the bike - nah it's doing that all by itself. How the hell is thing turning - well the obvious answer is it's going where you are turning your head towards. That's it just turning ones head. The once 80kph corner requiring a bit of rider concentration and effort, was just glided through at 80mph with little more than a glance in the right direction. The seated balance was perfect - zero bar weight required loose hands was well effortless. The suspension was unnoticeable. Stitching sweepers, chicanes and multiapex corners simply required the infinitesimal weight transfer that occured when turning the head. Seating remained inline with the bike. And ok, habit had me point a knee out but experimentation showed me that that was more for comfort than necessity.

But why the 80kph, and the 80mph comparison. I knew the gorge road very well, a cornering speed 80 kph was what I thought I read on the speedo out of the corner of my eye, and was only a little faster than my norm on the impulse. I was being cautious as the bike was on loan from the store! On the flat and straight I'd time to take a closer look, and spdiscovered the imported bike speedo was miles per hour. So in fact I'd just been smoothly trundling along at 1.5 times the speed I'd thought I was doing on one of the most challenging roads in the city.

Technology is a wonderful thing and perhaps explains much of that, but an improvement in corner speed of 35% with zero effort, or practice simply by changing bikes is I think extraordinary. More extraordinary is the minor detail that it's clear that it's not how the rider rides, but how s/he rides a particular bike.  Perhaps the impulse could have been riden that extra 35% faster, but I can say for certain not by me! I say that with confidence as I've clocked up about half a million miles on impulses, and riden them to the limit, even occasionally well beyond into stupidly terrifying, brake, suspension and tyre failure territory, for much of that. The RF900F was just a better balanced, way more refined package that enabled the rider.

The rf900 was effortless compared to the beasts of the early 1980s like the gsx750, more refined and sharp than the BMW k750, and preposterously more nimble than the Kawasaki gt750. The impulse at very low speeds ran circles around the RF900F for nimbleness but the smooth sharp turns at open road speeds made the fr900 very attractive.

What were the true limits of the RF900F I do not know, wisdom got the better of me. I was riding for the street, and I could quite easily imagine being caught out on a day with the flu coming on and loosing my licence because I cruised past a cop at 210 on my way to work. Or potentially crashing at stupid speeds because I was exploring the 900's limits. It also cost twice my annual income at that time.

As I've gotten older and heavier, I find myself riding ( the Impulse - still) more upright, with less hang, but slightly more drama ( dancing front end) at times. And slower… . We are now both classics. In the rain less hang, more upright, bike leaned more than rider,  means better visibility, and more time to react to road surface issues. It's not pretty and can feel wrong, but it's saved my bacon. But when the air is clear, and the surface is wet, hanging off the inside bike more upright gives one just a tiny edge if traction goes bye bye due to slick surface conditions.

Old bold riders have learnt to ride through the problems ahead, by adjusting their style to the bike, the road, and the weather, in addition to their rapidly degrading mental and physical agility.

[Jaybird180]

I just finished watching the Docu-Movie, ROAD. It's the story about the 4 VERY successful Road Racers, the Dunlops- Joey, his younger brother Robert and Robert's 2 sons William and Michael. I don't wish to give it away but it's an interesting film and there's some relevant footage pertinent to this discussion. See if anyone can spot the many references.

ROAD is available on Netflix.