How about the wider tire needing more lean angle? Would you say that's not something you really noticed or felt? I've had 200's on my gen 1, but what I'm remembering may have been backwards. In my mind I had more grip, so I could lean farther and I felt faster. But maybe I needed to lean more for just the same apex speeds.
We're really talking about a taller tire. A tire put on a rim that is slightly narrower than the tire was intended for is definitely going to compress that tire at the beads just a bit. What is compressed in width has to go somewhere and that would be outward. The diameter of the tire increases a little. The tire becomes taller. That is what was suggested to me. I really don't know if it's true or to what degree it's true but I definitely see an elliptical profile to these slightly wider tires as opposed to a circular profile with stock sized tires. It could be the wider tires are actually designed to have that shape. I'm pretty sure liter bike wheels generally call for these aspect ratios and liter bikes are much more designed for cornering than our big ol busas. Whatever the case may be, these tires are TALLER than the stock tire when installed to the stock rim. I definitely feel the extra height in the saddle. It doesn't take much extra height in the rear to increase a bikes response to turn in. An extra quarter inch will be noticeable. I'm sure road racers shim their shock a quarter inch or even less to achieve this effect. The rear is lifted, the forks are more straight up and down, rake is steepened, the bike turns quicker.
I don't believe the tire height or profile has an impact on the lean angles required. Lean angle requirements are all due to speed and the size of the turn radius. I don't even think the weight of the bike has anything to do with lean angle. Seems to me if you ride your bicycle at 30 mph and make a turn with a 20 foot radius, you lean the bicycle as much as you would lean your busa while doing the same speed in the same corner. Leaning a two wheel vehicle is all about transferring the centrifugal force caused by cornering. A bike is stable while straight up and down and headed in a forward direction. All the weight of the bike is centerd and focussed straight down through the bike and exerted on the lowest point of the bike (the tire contact patch) by gravity. Turn the bike and now you have centrifugal force competing with gravity. The centrifugal force has the same effect on the bike's stability that gravity does. You maintain stability of the bike in a corner by making the centrifugal force do the same thing as gravity does while the bike is standing straight up. While leaning in a corner, the centrifugal force is transferred and centered over the lowest point on the bike to keep it stable just like the force of gravity is centered over the lowest point on the bike when it is straight up and down. We lean to counteract centrifugal force because centrifugal force becomes as strong or stronger than gravity in a turn depending on how fast we are going and how sharp we are turning. If you didn't lean, the bike would high side due to centrifugal force exceeding the force of gravity. LOL That actually sounds pretty damn good for a guy with Fine Arts degree! If anyone with the background can help out on that, please have at 'er! These thoughts are mostly based on my intuition.
So dcn, I don't think the wider tire which probably is becoming a little taller tire than it was meant to be on the proper rim has any impact on your lean angle. IF you are going faster, that DOES require more of a lean than if you're going slower. Maybe that's why you felt you had tp lean the bike harder with a taller tire, you were going faster. Most definitely, a taller tire lifts the tail which steepens rake a few degrees. That, you will feel in the increased twitch in the steering. It really doesn't take much to create a noticeable effect. As for wider contact patch equalling better grip, I think
@jellyrug nailed it. It sounds like he knows the theory and has practical experience.
This contact area not being part of the coefficient of friction is really slapping my brain around. They sure like fat contact patches at the drag strip though...
Yeah they sure do! Look at the huge tires! An extreme example is the top fuel dragster. What I have been told is that the bigger and wider the tire is, the more matter there is to absorb tire heat. These tires don't have better traction because they have larger contact patches, they have better traction because they resist melting under 11,000 hp! Now look at the front tires of the dragster. They're like a bicycle tire but they have plenty of grip as long as they're touching the ground. Drivers have to keep that dragster straight and they need adequate grip in the front tires. They trust in a tire skinnier than a 600 cc sport bike tire to steer that dragster at 300 mph. Interesting to ponder all of this but I'm with you, I just trust a larger contact patch when I'm turning hard. LOL I'm not thinking about why I trust it when I'm riding the bike, I just trust it.
It's been so long since I used a stock sized tire on either of my bikes that I really can't compare how fast I corner with one or the other. To be perfectly honest, I think my skill has the most impact on how fast I corner. I probably would corner as fast on a stock sized tire. I've gone with lighter rims, aftermarket suspension and race tires. I'm not so sure any of those add up to higher speed in corners for me. It's a big bike, it corners well but it's still a handful no matter what you do. I can feel the improvements in equipment, I'm not so sure I'm good enough to really put them to their best advantage. It is really cool to feel it though.
