noamkrief Posted December 30, 2012 Report Posted December 30, 2012 Hey everyone. 20 hours ago I had an idea. To create a tool that will allow you to input your favorite road on google maps and it will tell you how fast you can go around each bend for a given lean angle. www.howfastcanigo.com Hope you guys enjoys it!!! I made it for everyone I know, friends, and peers at the forums. After programming for 20 hours straight, time to sleep... Quote
faffi Posted December 30, 2012 Report Posted December 30, 2012 When I were young, I used think I was sooo great. Heck, didn't I drag the alternator cover regularly on my GS550 while cornering? How could anybody possibly go faster? I would scoff at riders with chicken strips on their tyres. I dreamed of taking Isle of Man by storm. Then, as the years passed and I amassed more knowledge, I understood that there are so much more to going fast than being able to drag an engine cover at 40 degrees of lean. That being in the top 10 or even top 5 % of the fastest street riders simply doesn't mean anything when it comes to matchin the skills of the top 1 %, not to mentioned the top 0.1%. More importantly, being a fast street rider basically means being willing to take more risks, as even the craziest street riding is still way off track pace. That took me a long time to understand and accept, but the shells finally fell from me eyes. Why am I going on about this nonesense? Because A) riders may attempt to blast through corners at the calculated speed only to find they are in way above their heads and run off the road and because race pace doesn't belong on public roads where you risk putting innocent road users at risk and C) because having eventually matured I've understood that high speed/high risk riding doesn't belong on the street and hence should not be encouraged. Sincerely, Older and grumpier Quote
Lnewqban Posted December 30, 2012 Report Posted December 30, 2012 Very interesting and intense work, Noamkrief ! Checking my daily commute for the "turtle speed" and lean angle of 10 degree, I would be way over the legal speed limit for each of the sections of my trip. It would be interesting to apply it to tracks. Quote
ktk_ace Posted December 31, 2012 Report Posted December 31, 2012 Im sure different wheelbase will result in different speeds ; i might be wrong thou Quote
noamkrief Posted December 31, 2012 Author Report Posted December 31, 2012 Im sure different wheelbase will result in different speeds ; i might be wrong thou Yeah - sorry. you are wrong. Lets take an example: for a 200 foot radius turn leaning at 27 degrees a 2 wheeled vehicle will be doing exactly 39mph It doesn't matter if you are on a Harley, or a Honda CBR 600RR It doesn't matter if the motorcycle weighs 600lbs or 400lbs. It doesn't matter if you have racing slicks, or normal street tires. For a given lean angle, at a specific speed, all 2 wheeled vehicles would generate the EXACT same radius turn. I know it sounds strange, but it's 100% accurate. Check with your local physics professor. Same goes with airplanes if it helps you envision it better. A Cessna 172 at 140mph banking at 45 degrees would provide the exact same radius turn arc as a 747 banking at 45 degrees at 140mph Quote
ktk_ace Posted December 31, 2012 Report Posted December 31, 2012 Im sure different wheelbase will result in different speeds ; i might be wrong thou Yeah - sorry. you are wrong. Lets take an example: for a 200 foot radius turn leaning at 27 degrees a 2 wheeled vehicle will be doing exactly 39mph It doesn't matter if you are on a Harley, or a Honda CBR 600RR It doesn't matter if the motorcycle weighs 600lbs or 400lbs. It doesn't matter if you have racing slicks, or normal street tires. For a given lean angle, at a specific speed, all 2 wheeled vehicles would generate the EXACT same radius turn. I know it sounds strange, but it's 100% accurate. Check with your local physics professor. Same goes with airplanes if it helps you envision it better. A Cessna 172 at 140mph banking at 45 degrees would provide the exact same radius turn arc as a 747 banking at 45 degrees at 140mph Thanks, I'll check it up over coffee with my physics majoring buddy Quote
faffi Posted December 31, 2012 Report Posted December 31, 2012 That is unfortunately not correct, noamkief, since tyres have width. If they had no width, wheelbase, weight, CoG would all be irrelevant. But since they have width, usually substantially these days, a longer bike must lean more than a shorter, a lower bike must lean more than a taller, and a wider tyres means more lean than narrower ones for any given corner speed. Also, since we do not ride around in endless circles, things like time/distance spent on turning in matter greatly in how quick you can go through a corner. Quote
Hotfoot Posted December 31, 2012 Report Posted December 31, 2012 As is often the case, the simple physics formula makes some assumptions, and this is something we must all be aware of - many educational texts talk theory but ignore the effects of rider position, tire width, condition factors like wind, coefficients of friction that varies with surface and temperature, etc., etc. Here is a pretty good article that describes the effect of tire width and wheelbase - plus some good info about gyroscopic effect. http://en.m.wikipedia.org/wiki/Bicycle_and_motorcycle_dynamics Quote
noamkrief Posted December 31, 2012 Author Report Posted December 31, 2012 That is unfortunately not correct, noamkief, since tyres have width. If they had no width, wheelbase, weight, CoG would all be irrelevant. But since they have width, usually substantially these days, a longer bike must lean more than a shorter, a lower bike must lean more than a taller, and a wider tyres means more lean than narrower ones for any given corner speed. Also, since we do not ride around in endless circles, things like time/distance spent on turning in matter greatly in how quick you can go through a corner. You are 100% correct!!!! And I didn't want to get into that because most people wouldn't understand this concept. So let me make a clarification. When my program calculates lean - it calculates total SYSTEM LEAN. So for example: if your actual bike lean angle measured 45 degrees but with 190's on the rear, your SYSTEM LEAN is probably about 40 degrees. Then the rider is hanging off with amazing body position bringing the SYSTEM LEAN down to 49 degrees. the 49 degrees is the lean angle that I calculate. The SYSTEM LEAN basically the angle between the contact patch of your tire, and your CG. So to clarify - my app doesn't know and doesn't care how you achieve the preselected 50 degree lean. You can lean the bike 45 degrees, and hang off to achieve a total system lean of 50 degrees. I added a page to the website that explain motorcycle dynamics. http://www.howfastcanigo.com/howitworks.html Quote
richard_m_h Posted January 3, 2013 Report Posted January 3, 2013 Any chance of kilometres per hour for those of us that aren't in the USA? At first sight the speeds look mildly suicidal on some of my favourite roads but I'll have to check my speed next time I'm out. on second thoughts, it looks good apart from the off camber corners. Quote
csmith12 Posted January 3, 2013 Report Posted January 3, 2013 The speeds look mostly pretty good from the routes I have plugged in. Although camber may play a large role for me. Some of the really sharp corners that have good camber are listed a bit slow. Quote
noamkrief Posted January 4, 2013 Author Report Posted January 4, 2013 Affirmative!! Google maps does not provide road camber!!! Sorry The program is still accurate even though it doesn't factor road camber... Here is why: When you select your desired lean angle you are selecting a line between the contact patch of your tire and the Center of Gravity of the entire system - bike + rider. That line has an angle relative to - THE HORIZON, not the road. That's how the mathematical formulas for lean angles are composed - with Horizon being measured against, being the horizon is always 90 degrees perpendicular to the force of gravity. So if you selected a lean angle of 45 degrees and you are on a road with a positive camber of 10 degrees. The lean angle calculated is 35 degrees relative to the ground. So yes - on that corner my software would read "slow" but it's still correct because that's the speed for 45 degrees lean relative to the horizon. Again - sorry I couldn't do camber calculations which would be super easy if only google maps provided this data - data they don't have i'm almost 100% sure. This app was mostly developed to find cool fun roads. If you are like me, I like using google maps to find nice fun twisties. But looking at the map, it's very difficult to judge how wide or tight a turn is. So you might find a nice road 100 miles away that looked on google maps like it had tons of fun turns, but when you get there, the turns are super wide and to get any sort of fun lean angle (35 degrees or more in my opinion) you'd have to be doing 100mph. Quote
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