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Discussion Starter #21
There is no downforce on a motorcycle. It would be impossible to sustain it when the bike's angle to the roadway changes when cornering. The fastest 1 liter sport bikes have a top speed of around 180 mph. Moto-GP bikes are over 200, but not by much. Even since they cut maximum displacement from 1000cc to 800cc, I am not sure how much top speed was cut (if any).

Bike aerodynamics ARE terrible. If anything as good as a car, the top speed would be really high given the frontal area. Ride a bike at 70 mph and close in tight behind a big rig and if not careful, you will briskly accelerate right into the rear of it. Ask me how I nearly found this out the hardway.

Phil
 

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Discussion Starter #22
However, these are the things that I think are the biggest shortcomings for the bike:

1. Center of gravity is too high to utilize 100% of available traction.
2. Transitioning into/out of a turn takes more time due to #1.
3. Suspension geometry reduces reliable traction in a turn.

Keep in mind that if you the contact patch flat on the ground, the available acceleration in a turn is almost completely determined by the tire compound (not by the tire size, not by the weight on the tire). Motorcycles keep the contact patch large by using round cross sections for their tires so that the patch doesn't change when the bike leans. However, as I said before, the suspension can't handle bumps as well, and so rough curves suck far more on bikes than they do in cars.
#1 is true, but is made worse by increasingly short wheelbases and reduced weight, along with higher power.

#2 is also true, but it should be noted that a bike can not turn without lean angle, and that takes time to achieve. The bike does tend to rotate about the center of gravity with contact patches moving one way and the top of the bike the other. Honda once mounted the fuel tank on the underside of a GP bike to lower the center of gravity. This harmed handling as the load of fuel was now further from the center of gravity. They quit that idea. Normal center of gravity with rider is about where the rider's groin is. Pretty high for something with about a 55" wheelbase.

I do not agree it is suspension geometry that reduces traction in a turn, unless this means that bumps still travel upwards and the movement of the suspension is at the same angle as the bike is leaned over. Honda experimented with designed in frame flex to allow bumps to deflect the chassis slightly under hard cornering. On today's sport road bikes, with sticky tires, and over 45 degree lean angles (1G), bikes still generally run out of ground clearance (more than 45 degree lean) before grip. Getting to this state requires a very good rider.

My experience with cars on my sport motorcycles has shown me it is difficult to keep up on slower, quick transition turns with few straights. Wide open corners and straights make it much easier. As a result, something like a tiny Miata can be more difficult than a Corvette, all else being equal.

Phil
 

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I do not agree it is suspension geometry that reduces traction in a turn, unless this means that bumps still travel upwards and the movement of the suspension is at the same angle as the bike is leaned over.
So you don't agree except that you do agree? You just re-stated what I said, that the suspension geometry is at the wrong angle in a lean. What don't you agree with?
 

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Discussion Starter #24
So you don't agree except that you do agree? You just re-stated what I said, that the suspension geometry is at the wrong angle in a lean. What don't you agree with?
You missed the word "unless". I disagreed UNLESS you meant what I described following the word "unless". Turns out you did mean what I thought when you said "suspension geometry" and we do agree.
 

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I rode a Buell XB90 CityX for a few years before selling it for personal reasons. I enjoyed many spirited rides through the Sam Houston State Forrest on Sunday mornings.

I thought I was pretty fast, straight-aways at 100 mph and corners rated at 35 mph where attacked at 50+ mph.

After I got my Cayman S, I went down the same road and was pleasantly surprised that I was able to take it at the same speeds if not faster.
 

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I used to race on a prep honda rvf, and a Yamaha R6. Had the chance of race internationally and become a pro (but at that time I didn't had the financial support of anybody, and I was 18-21 of age)

Compared with previous gen cars, It was so different (faster) that it was not even funny

Now with all the stability management, dynamic load balancing, brake distribution, active suspensions and traction controls in cars, the playfield is more even, I never thought that a car would give similar sensations as a sports bike, but a Cayman comes close

As somebody did find out above, the real difference is down force, get the downforce out of a F1 car and a GP bike will do 2 laps per each of the F1

Nice thread, good memories

Note: SportBikes now are incorporating traction control and lean sensors, front and rear wheel lift control and abs (you can even do a full acceleration while your knee is touching the asphalt and the bike electronics take charge)
 

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I do not condone street racing, but wanted to ask if anyone has ever come across a motorcycle ridden well enough to stick with you during spirited Cayman driving?

While it was in 1998 BMW M3 sedan, I did have this happen to me once. Three sport bikes came up behind me, right when I got to a favorite section of a road I frequent. I waved them past, but they did not want to pass. I hit the gas, as usual for this section of road, and two dropped back immediately (Honda and Ducati), but the third guy was no joke. Glancing in my rear view mirror, his Yamaha R1 was over hard on its side, the guys knees on the ground. Even under hard braking, he was still there. He could have killed me on acceleration, but elected to stay behind.

Got to the end of the road, and he slowly passed me, and gave me a big thumbs up. Was fun, and nice to see the bike ridden that well. I am not sure he (or anything) could stick with a well driven Cayman.

Phil
Phil:

This is a subject I have a lot of experience with!!!

I do a lot of sport touring on motorcycles. When we get to the "good roads", which is what I call twisty, abandoned rural roads of a type it sounds like you are familiar with, we tend to let the stops out a bit. I have a lot of miles on such roads and my riding pals do too.

On a good sport-touring bike, ridden well, a good, sporting pace is about 6 tenths of what the bike is actually capable of on a track in controlled, repeatable conditions. The problem is, you often don't know the road very well, the surface of any public road is a constantly changing thing, there are driveways and trucks on the back side of turns that want more than their half of the road, tar snakes, gravel being thrown up from the shoulders on turns etc etc... So you have to leave quite a bit in reserve if you want to live to see another great riding day.

I have done a few motorcycle track days, but I'm by no means an expert track rider. I cannot get all the available cornering out of either of either of my two bikes...Doesn't mean I can't really enjoy them, though.

One weekend, a friend had an electrical problem with his VFR mid-trip. We figured the bike was out for the count. I volunteered to ride 150 miles home and get the Cayman to give him a contingency in case he couldn't get his bike running again. He and I could enjoy the rest of the weekend driving instead of him just bagging it.

While I was gone, he found a dealer nearby willing to diagnose and fix his bike within 2 hours...a minor miracle on a Memorial Day weekend. When I returned with the car, another rider in our group, asked if he could park his Gold Wing and ride with me the next day.

We had a ball. I was surprised to find that none of the other riders could keep up with us on these back roads. I've since had a few other experiences where I'm driving with a group of bike friends. I'm always leading the pack and waiting for the others to catch up at the turns.

A few weeks ago, I had a trip planned to NC-Deal's Gap area. I had planned to take my BMW 1200RT, which is a terrific Sport Touring machine. The drive is about 700 miles each way from my house. I'd injured my right hand tripping over one of our cats in the living room (not kidding...The cat's fine, BTW) I didn't want to risk re-injuring the hand or having an off because I couldn't get my hand to work when I needed it to, so I decided at the last minute, to take the Cayman.

The car was superb this time...I'd added coil-overs, new seats and 0.5 degrees of negative camber since the last time. I usually avoid running Deal's Gap on weekends because it's loaded with punters and you rarely get to go fast at all. There are a lot of better roads in this area that are not so crowded. The guys wanted to hang at the Deal's Gap Motorcycle Resort for a while. We were sitting around doing almost nothing and I announced that I thought I'd take a quick drive up and down the Gap for a lark. One of the guys volunteered to ride shotgun and off we went while the others perused the parking lot and the "Tree of Shame".

On the return trip, someone on a red Yamaha R6 or R1, in full gear, was in front of me and just dusted me completely. He was leaning knee-down-hard in every turn and obviously knew the turf. It was one of the best demonstrations of how to really ride a sport bike hard on a two-lane I've ever seen. Not many can or are willing to do this on public roads and this road isn't very wide. Nor is it blessed with the sort of constant radius turns and perfect pavement that gives sport bikes confidence. Nevertheless, he was perfectly poised on his bike and never put a foot wrong. He would match my corner speed, then out-accelerate me on the short straight sections. When he got nearly out of sight, he'd pull over and start it all again...Really and awesome display of riding.

That was the only time a bike has ever outmatched this Cayman on the street. I don't race...ever, but it's often quite obvious who's got the advantage when you go for it on a track weekend or one of these back-road excursions. I was outclassed and I doubt even a turbo would have saved me.

For me, the risk/reward of doing/learning this sort of riding is just not worth it. Leaving the road in a solid German car with air bags and crush zones is expensive, but you will likely live through it. Doing the same on the sport bike is not so certain, even with full gear, especially if you are over 30 years old. The other thing about bikes is that things like pebbles or a little gravel on the pavement will really upset things when you're leaned over on a bike. The same in a car might cause the wheels to slide a few inches. That's easily correctable in a car like the Cayman.

I still love riding, but I'm not so interested in pushing the envelope that hard with a bike. One can find passing opportunities on a bike much easier than in a car. This is due to the power-to-weight of a decent bike being much better than 99/100ths of cars on the road and...bikes are narrower. This allows them to get out in the passing lane sooner and get back in sooner. The passing advantage of bikes on 2 lane roads really makes a bike more fun. The other advantage to narrow bikes is that you can apex he upcoming turn after a pass and you don't have to slow down so much.

There is a feeling of being "out there" on a bike instead of inside a passenger cell while traveling that is also very nice. You see things you just would never see in a car. It's a great and different perspective.

When I'm back-roading it with bikes, I'm running with both windows down, A/C off and tach in the top half of the revs, just like at the track. The feeling is similar to running hard on a bike, but with only about half of the concern about the road surface to think about...and I have the security of the passenger cell if things go wrong. Of course I'm going to be able to hit those turns harder than the bikers can...unless the biker is that guy on the red R6!

:cheers:
 

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Nice write up Sixisenuff!. I miss my Honda VFR, best bike I ever owned. For me, the Boxster was the best compromise and to top it off, my wife picked it out for selling the bike!
 

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Nice write up Sixisenuff!. I miss my Honda VFR, best bike I ever owned. For me, the Boxster was the best compromise and to top it off, my wife picked it out for selling the bike!
J:

Sadly, it was a VFR that wouldn't start on Saturday morning. That's why I went back home on my BMW R1200RT and got the CS to provide an extra seat. Apparently, they had a common problem with the starter circuit. Can't remember now what the exact problem was but we could not fix it ourselves. We tried.

They are great bikes otherwise. His is a pre-V-Tech bike and it's in beautiful shape. He now also has a screaming yellow Gold Wing that he likes to call "The School Bus".
 

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I was thinking about this thread while driving today. I put myself in the same category as six, a few track days, ridding spirited when on a good ride with good riders, knowing that "fast" on the street is nothing compared to "fast" on the track. The same goes for cars too. I now know that I will NEVER push my car on the street like I will at auto-x. But, given the right opportunity I think my limits on the street are closer to closed course speeds in the car than on the bike and that is why I think the average Joe rider will find the Cayman pulling away in the twisties. The average Joe is also pretty slow.....

Funny coincidence, my current 2 wheel ride is also a BMW, like Six, but mine is a K1200.

Another funny coincidence! I recently picked up a project bike, a 64 Honda CB77 305 Superhawk. On the honda 305 forum I found a thread on someone else's project that is very similar to the route I want to go, larger carbs, same big-bore kit.... That guy recently picked up a Cayman.
 

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Discussion Starter #33
Fun writeup sixisenuff! At the age of 57 (2 years ago), and after 30 years of riding, I decided it was time to call it quits and let my motorsports enthusiasm be enjoyed with four wheels vs two. I found I always wanted to ride fast, and as you know, mistakes on motorcycles are often unforgiving to the human body, and the chances of those mistakes go up fast with increased speed. Too many unpredictable dangers as you said. I often rode down the road once to make sure it was clean, safe, etc., and then repeatedly made fast passes up and down that section of pavement just for fun. I became pretty quick doing that. But, on the unfamiliar road, the motorcycle pilot can not enjoy the benefits of being saved by electronic controls if he makes a mistake, such as not recognizing a decreasing radius turn.

A well ridden sport bike (rare) will be very difficult for the Cayman to catch in the corners. I think it can match the bike, but would never be able to pass. Just too close. The Cayman can brake harder, but will be completely humiliated when the power comes back on. Riding the sport bike SKILLFULLY, when all the planets aligned and everything worked that day for me, is incredibly rewarding. More so than the car. But at the same time, if it was a bad day, I felt like I was lucky to be able to zip up my riding boots and leathers all by myself. Not good riding times ON THOSE DAYS.

The last bike I had was an Aprilia Tuono, an Italian bike that was such an animal, the thing almost dared me to tame it. Wheelie prone to a fault, with a one liter Rotax V-twin making 133+ hp, the engine dominated its character, something it had in spades. Fired up in the morning, it idled with a fast impatience that hinted at its need to go fast, perhaps not unlike a high strung race horse at the starting gates. Once aboard, it was impossible not to notice the unfiltered visceral feel. My brain felt hardwired right to the combustion chamber, with a clearly felt hard and brutal punch on every firing in its big 4” cylinders, beginning at 4000 revs, coming on the cam around 6500 and pulling very hard to its 10,500 rpm rev limit. It didn’t like running below 3500 revs, snorting and hesitating, clearly telling me, “let’s get to work” and the heck with all this sub 50 mph 1st and 2nd gear nonsense. It was certainly not over refined to the point of having a flat personality! The Tuono felt like a willing partner, always wanting to play hard like a puppy or kitten. But in this case, an undisciplined adolescent Tyrannosaurus Rex, always reminding me, “we can have fun, but I can squash you like a bug”. Fortunately, it never did, and I really enjoyed the Tuono.

Overall, I will say that I thought my motorsports itch could be equally satisfied by a sport bike or something like the Cayman. The itches are different, and both need different types of scratches. But for now, I am OK with the Cayman. It brings calmness, refinement, and a micrometer like precision to the driving experience. It does not encourage me to be a rowdy nut like the Tuono did, and nowadays, at my age, that is not a bad thing. The Cayman has nowhere near the visceral connected feel the bike has, but the Cayman has a multitude of other pluses that are increasingly appealing to me. All that said, I still have very fond two wheel memories of some knee dragging in corners, rear wheel lifting braking, and retina detaching acceleration and the wild Tuono.

Phil
 

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Agree 100% with Six. In general the difference between high performance bikes and cars on the street is less about the machine's limits and more about the driver's willingness to approach those limits. The higher end of the performance envelope (say, eight tenths or more) is just more accessible and less risky in a car. If both are piloted at the limit, a $13,000 sport bike will indeed be a match for pretty much any sports car on all except very bumpy or very twisty sections.

I've been riding for 25 years, lots of sport touring and plenty of very spirited backroad blasts. [Six - You brought back fond memories of the roads around Deals Gap from a prior life living in the southeast. Cherohala anyone?] Since I started tracking the Cayman, it has become very clear to me: I prefer bikes on the road and cars on the track.

  • A great road: Give me a bike at 7 or 8 tenths, or even 5 tenths if I'm just enjoying a beautiful ride. I almost always ride at a "spirited" pace, but almost never an aggressive pace. Of course "spirited" is a relative concept...:D At the same pace a car does not give me the same enjoyment.
  • Track: Give me a car at 9.5 tenths or more. I'm willing to push a car on track and explore the limits in a way I would not be comfortable doing with a bike, and would not attempt on a public road with anything.
How great to have access to both.....

:cheers:
 

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Fun writeup sixisenuff! At the age of 57 (2 years ago), and after 30 years of riding, I decided it was time to call it quits and let my motorsports enthusiasm be enjoyed with four wheels vs two. I found I always wanted to ride fast, and as you know, mistakes on motorcycles are often unforgiving to the human body, and the chances of those mistakes go up fast with increased speed. Too many unpredictable dangers as you said. I often rode down the road once to make sure it was clean, safe, etc., and then repeatedly made fast passes up and down that section of pavement just for fun. I became pretty quick doing that. But, on the unfamiliar road, the motorcycle pilot can not enjoy the benefits of being saved by electronic controls if he makes a mistake, such as not recognizing a decreasing radius turn.

A well ridden sport bike (rare) will be very difficult for the Cayman to catch in the corners. I think it can match the bike, but would never be able to pass. Just too close. The Cayman can brake harder, but will be completely humiliated when the power comes back on. Riding the sport bike SKILLFULLY, when all the planets aligned and everything worked that day for me, is incredibly rewarding. More so than the car. But at the same time, if it was a bad day, I felt like I was lucky to be able to zip up my riding boots and leathers all by myself. Not good riding times ON THOSE DAYS.

The last bike I had was an Aprilia Tuono, an Italian bike that was such an animal, the thing almost dared me to tame it. Wheelie prone to a fault, with a one liter Rotax V-twin making 133+ hp, the engine dominated its character, something it had in spades. Fired up in the morning, it idled with a fast impatience that hinted at its need to go fast, perhaps not unlike a high strung race horse at the starting gates. Once aboard, it was impossible not to notice the unfiltered visceral feel. My brain felt hardwired right to the combustion chamber, with a clearly felt hard and brutal punch on every firing in its big 4” cylinders, beginning at 4000 revs, coming on the cam around 6500 and pulling very hard to its 10,500 rpm rev limit. It didn’t like running below 3500 revs, snorting and hesitating, clearly telling me, “let’s get to work” and the heck with all this sub 50 mph 1st and 2nd gear nonsense. It was certainly not over refined to the point of having a flat personality! The Tuono felt like a willing partner, always wanting to play hard like a puppy or kitten. But in this case, an undisciplined adolescent Tyrannosaurus Rex, always reminding me, “we can have fun, but I can squash you like a bug”. Fortunately, it never did, and I really enjoyed the Tuono.

Overall, I will say that I thought my motorsports itch could be equally satisfied by a sport bike or something like the Cayman. The itches are different, and both need different types of scratches. But for now, I am OK with the Cayman. It brings calmness, refinement, and a micrometer like precision to the driving experience. It does not encourage me to be a rowdy nut like the Tuono did, and nowadays, at my age, that is not a bad thing. The Cayman has nowhere near the visceral connected feel the bike has, but the Cayman has a multitude of other pluses that are increasingly appealing to me. All that said, I still have very fond two wheel memories of some knee dragging in corners, rear wheel lifting braking, and retina detaching acceleration and the wild Tuono.

Phil
Phil,

I have a Cayman and a 2008 Aprilia Tuono Factory RR. You nailed the description of the Tuono on the head. Such a great description that now i need to go jump on her again.

Sent from my GT-P7510 using Tapatalk 2
 

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Sadly I'll have to agree too many motorcycles aren't ridden well and the results can get ugly. I bought my Cayman S partially to replace my urge to ride and race motorcycles. I raced (amateur) and did track days for 7 years until I broke my back during practice for my final race. I blame it my Aprilia RSV1000R Factory wanting to go a different direction and high siding me. :eek:

I still ride motorcycles, more upright Ducati and MV Agusta (I'm over Aprilia) and my track days are behind me...expect for in April I got to take out on the New Orlean's track an 1199S Panigale. WOW, the new electronics' package makes it easily for guy that hasn't been on the track in over 6 years to have a blast. When I take out my Desmosedici RR it's intimidating how fast and raw it is.

I had the Cayman out on the track. It's just not the same visceral sensation as a motorcycle but my wife doesn't want to kill for doing it, well that is until she see the bills. I've realized I don't know how to drive it fast and smooth in that environment, so I'll probably be taking some driving schools.

Back in the days I lived outside of Atlanta I rode sportbikes all over TN, NC, GA and Deals Gap area and car drivers nearly always frustrated me with there slow pace relative to what I wanted to go. So I took it to the track (and riding schools), smartest thing a motorcyclist can to do improve there skills and hopefully make them a better, calmer rider on the street.
 

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Amatuer raced motorcycles as well, really enjoyed it! Even drag raced for a bit with a turbo charged Hayabusa that doubled as my daily driver. After several track crashes and one on the street, I really cut back on the riding (actually selling my last bike right now).

To replace it, and I honestly find it much more enjoyable, I picked up a shifter kart and never looked back. All the fun, way more corner speed, way less cost, and much MUCH safer :) Give that a try if you haven't, they are incredibly fun to drive.

Karts replaced my motorcycles at the track, and the Cayman replaced them on the street. Very happy, and so is the wife ;)
 
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