Jump to content

All Activity

This stream auto-updates     

  1. Past hour
  2. I understood the concept as pushing up to help lock the knee up and against the tank. Weighing the outside seems more of a controlled and directed action, whereas weighing the inside basically catches our body from falling so to speak. I know this as I've done both, and I can also add that weighing the inside has worn me out to the point of getting serious calf-muscle cramps toward mid-afternoon, while weighing the outside did not present such a challenge. While the question is does it matter which one is weighted, I would say no from the way the question was phrased, with the assumption that we are talking about how the bike would react. Another downside with weighing the inside peg I recall was the impedance of free leg/foot movement for proper posture and clearance.
  3. Yesterday
  4. Who all is going and where are you staying? I know I'm heading there, Red_Baron is going to be there, as well as El Colibri. Let us know!
  5. Looks like we're all going to be at Barber! I tried signing up for the 2 Day, but someone took the last slot....lol. So I am doing a Single and then the Half Camp, trying to get at least Level 1 & 2 completed. Really looking forward to this!!!
  6. Last week
  7. Good day all. Steve Kelly here. 57 years young, looking forward to another 20+ years on two wheels. Been an MSF Rider Coach for over 10 years coaching the BRC, BRC2, & ARC. Retired USMC Helicopter pilot and sound engineer for local & regional bands. Been riding cruisers ('73 Ironhead Sporty, '95 FLSTN, '98 Valk) and baggers ('81 GL1100 Standard, 2014 GL1800BD - F6B) for 20+ years, got 126,000 miles on my 2014 F6B. I have lots of fun the Georgia/Tennessee/North Carolina back roads! Being retired doesn't suck.... Never owned a sportbike, but I always wanted to learn. Coaching the Advanced Rider Course on the F6B was leading to too many footpeg replacements - wrong tool for the job - and the '95 Harley was no better. As luck would have it, a 2008 BMW K1200S came my way on 30 Dec and after 2 months and 2500 miles on her, I decided that I needed to do more than just read TOTW2 and watch the video. So...I just signed up for the Barbers School in May - really looking forward to being on the other side of the coaching for a change. Looking forward to learning new stuff on these "go-faster" bikes. Something for cornering that is just a bit more than "Slow, Look, Press, Role".... Attached is a pic of "Lena" & I in Camden, Alabama Cheers, Steve
  8. Greetings!!!! I attended several years ago in Vegas and was blown away in how much my riding improved. I’ll be returning next month to the Streets of Willow Springs and am hopeful for similar results. I’ve spent some time on the track (track days and racing) but am looking to get more serious in my ability to ride more efficiently and learn how to better communicate with the bike. In reading and re-reading TOTW II and “Soft Science”, I now better understand where I can improve my speed and confidence. An area where I’m looking to improve upon is Charging and being able to get on the throttle before the apex, or preferably sooner. When I think back to my riding, I’m getting on the gas at the Apex (or, perhaps being honest with myself, after the apex) and this is where I’m losing a bike length or two (or three or four) to my competition. I’ve become obsessed with the attached pic from TOTW II, page 29. This is exactly what I’m doing wrong and the book lays exactly what I need to do. This will also allow me to explore my limits of traction. If I can better understand this in my riding, I will fly home a happy man. See you at the track!!! Foxxy
  9. Comotocon, the company many of us haven’t heard of is growing. Comotocon Holdings, which already owns Revzilla and Cycle Gear, has acquired J&P Cycles in order to increase its presence in the American V-twin market. Article here: https://www.asphaltandrubber.com/news/comoto-revzilla-j-and-p-cycles-acquisition/
  10. I know nothing about this topic, basically. However, when I attended a gravel rally, I was told to keep weight on the outside peg and push firmly against the fuel tank with my outside knee while turning standing up. For me, that helped massively. Suddenly, it was easy to steer with the rear using the throttle, and slides could be controlled. I immediately felt safe. Whether this mean anything for road racing I cannot say. I have also read many times over the years that top rank riders can shift their weight between the inner and outer peg up to 20 times in a single corner. Apparently, they do this to control drift and grip. Way beyond my scope to try - I'd likely crash right away because my limited mental capacity would be spend on dancing on the pegs rather than controlling the bike and reading the road. Finally, riders like Tony Elias and other shorties commonly let their outside foot dangle above the peg while cornering, a result of hanging way off and having short legs, I presume. They still win races. So perhaps this is just another tool available to be used by the rider, but not mandatory for success?
  11. Yes, I’ve looked into cutting the cord and streaming options. It does appear getting BeIN through Sling is the most economical option ($60+/yr), if the goal is solely being able to watch MotoGP. Unfortunately, for our house, cutting the cord isn’t an option (many out of market programs only available through our current provider). Also, there’s a big difference between race coverage on BeIN and MotoGP/Videopass, which offers access to free practice, press conferences, races going back to 1992, etc. I was simply wanting to inform the people on the forum that there’s a discount for Videopass currently available.
  12. Earlier
  13. Have you looked into/considered TV streaming options? I know via my Fire TV I get enough that I don't miss cable tv.
  14. Wanted to share: @motogp on Twitter is offering 10% off for this season’s subscription - via the link found there. That plus the current $:€ exchange rate makes this season $136.27 vs the standard price of $159.99 (when you see it offered in $’s).
  15. I have been told that weighting, or rather pressing down on the outside peg allows you to corner faster and safer, as it encourages you to put your head and shoulder weight, and not your butt, inside the turn (aka: kissing the mirrors), which requires less lean angle in a given turn/curve. (Your upper body weight leaning into the turn replaces some of the bikes weight it would use in the lean, requiring less lean angle on the bike) Ive taken turns where it seems the bike stays almost upright, and I'm able to hug the inside line nicely in the apex of long curves. It helps as well as it puts an outside downward force to the rear tire for stability/traction. I havent been riding a long time, but I have been testing taking turns in this fashion, and it definitely seems to help me.
  16. Sorry that's sort of what I meant -- if I'm on the 'edge of a penny' for contact patch then to lose traction I only need that edge of a penny to hit something without friction (and the keying/adhesion etc); with a larger contact patch then you have more of an area which would need to be disrupted in order for the maximum grip to be reduced.
  17. One thing I’ve read about is that DOT certification is a manufacturer assertion.
  18. yakaru, I'm not sure it is as much a question of friction being applied in more places (unless more 'keying' is happening) as it is the extent to which the contact patch 'coefficient of friction', at that particular moment in time (so factoring in the portion of the contact patch that has been disrupted) has not reached the point of 'slip'. In some of the articles I've read the point of slip is expressed algebraically and can be calculated (theoretically) if all the other variables in the equation are known. Dave
  19. Thanks, Dylan. I've read about these dynamics in various articles but have never seen them summarized in such a succinct manner. Very helpful indeed. I would add I think 'keying' may also be a dynamic property (in addition to static) given the extent to which keying is constantly changing as tire energy dissipation, surface and interior heat, abrasion / shearing stress, and load change. For those who may be interested in the engineering details, one of the websites I found helpful is multiscaleconsulting.com. In their publications section are various papers on rubber friction and contact mechanics. A warning - their papers are filled with lengthy algebraic formulas supporting their analysis. I try to just focus on their key points and not get lost in all the math. I think the next evolution of this for me will be to learn how to read a tire so I understand what is happening to it and my traction/friction equation. Dave
  20. If this has already been stated I apologize -- but I want to go back to the 'tug of war' example. Let's make it a bit more of a "water ski" example where you're being drug along on a rope and resisting by putting your heels into the ground. In isolation it shouldn't matter if one or two heels are dug in, however, if something in the scenario happens where the grip of one heel is jostled loose then you immediately face plant. With both feet any scenario on one can have the 'load' taken up by the other during recovery. In a similar way, a larger contact patch allows the friction to be applied in more places should there be any disruption in another?
  21. Your collection of data and research shows you are barking up the right trees. Here's some more data regarding tires: Per the Dunlop engineers tires grip in 4 ways: 1) Adhesion--the temporary chemical bond between the tire and surface. 2) Keying--the tire deforming and filling in all the nooks and crannies of the asphalt or squishing into the depressions. 3) Abrasion--the tire tearing from itself or wearing away. 4) Hysteresis--the energy storage and return by the rubber and partial conversion to heat. The first two can be looked at as static properties and the last two dynamic properties in my opinion. I'm still learning on all this stuff and when talking to the tire engineers, they don't have all the answers either. Heck, aviation engineers still can't all agree on exactly how a plane flies through the air!
  22. I've been trying to develop a better understanding of traction over the last couple of months as well. As such I've read a number of articles and technical papers about friction, and specifically, friction as it applies to the interaction between rubber and hard/asphalt surfaces. As I understand it, there are four types of friction: static, sliding, rolling and liquid. I may be wrong but I think the Amontons-Coulombs three laws of friction do apply to tires/rubber as it relates to "static" friction - tires may not be rigid but they are solids. However as soon as you move to sliding and rolling friction (which are the only applications we really care about) the three laws need to be modified for rubber specific properties and what happens between rubber tires and asphalt friction as heat and tire deformation change. Attached below are a couple of articles that help explain rubber-hard surface dynamics that cause rubber related friction to act differently. After reading these articles (and several others) I am now thinking about the "coefficient of friction" between tire rubber and asphalt, at any given moment in time, as being determined by the following ... For road surface … its material, texture, condition (including extent of surface oils/moisture present), temperature, gradient/camber. For tires … their material, construction, condition (also including extent of oils present), energy dissipation and resulting temperature (a hugely significant factor), stiffness, extent of flex/deformation and how well the rubber fills asphalt surface gaps and creates microasperity contact points (so yes, contact patch size matters), and finally tire pressure (which has direct impact on extent and rate of tire temperature changes and flex/deformation). Pressure or load between the tires and road surface … from both vehicle weight and riding forces (ergo cornering forces) The list may be missing a few things, but I think it hits the major elements. And since cornering force has such high impact, I think about the extent of "cornering force" being driven by a number of factors as well, including ... Weight Vehicle balance (shifting of weight, pitch and angle) Kinetic energy (speed) Corner radius and extent / rate of radius change (e.g. closing versus opening radius corner) Centrifugal force (directional inertia) Centripetal force (force acting on a moving body at an angle to the direction of motion, tending to make the body follow a curved path) Rolling resistance (from braking and accelerating forces) I'm still learning on all this (traction / friction) so feel free to correct me where I am off base. Dave Guidance-Rubber-Friction.pdf Rubber_Friction_and_Tire_Dynamics_A_Comparison_of_Theory_with_Experimental_Data.pdf
  23. Thanks very much. We have more on the way!
  24. faffi

    Then vs now

    Rutter is a multiple winner of IoM, so should be comparable. Sure, it was not set on the same day by the same rider, and as such not a perfect comparison, but it should give a fairly realistic picture.
  25. WHR

    Then vs now

    I think I need to donate my 1997 VFR750F to the school only on condition that it be built as a "demo" bike for students to marvel at it's awesomeness! :-) Seriously, I believe this is a bit like comparing apples to oranges, not to mention all the other factors involved. A better comparison would be the same rider (Rutter for example), riding both bikes on the same day.
  26. I can't answer your question, but I can tell you one thing. Snell approval is overrated. AFAIK, all it does is add $$$ to the cost of a helmet. "They wouldn't be DOT approved in the Asian market." They were probably not Snell approved either. That would account for the cost savings. I wish we could tag someone in a post. I'd like to know the school's stance on this as well. I don't want to assume they would, even if an ECE approval is above the DOT standard.
  27. Hey Dylan, I am sure you get this a lot, but..... Reading the information you put on the board feels like finding clues in mystery novel. Like a real-life Divinci Code deal, only for motorcycle addicts. I am still buzzing with the classroom time on physics, biology, mathematics, psychology, and the riddle of why motorcycles turn. I really appreciate your contributions here.
  28. faffi

    Then vs now

    For comparison, the premier class has seen less performance gains than the fastest class at Isle of Man (current lap record is set with an average speed of more than 135 mph) - in 1990, Gardner lapped Phillip Island at 1:34.560 during the race. Current race lap record is 1:28.108, set by Marc Marquez in 2013. If I take that equation, starting with 115 mph as an arbitrary average speed of Garner, I end up with 120.8 mph for Marquez. Interestingly, the best race lap in 2019 by Vinales took 1:29.322, or 119.7 mph using the same math. This is a rather flowing track where handling is more important than power, though, whereas IoM benefit quite a lot from more power. Report to moderator 188.126.196.22
  29. faffi

    Then vs now

    In 2018, Micheal Rutter punted a stock Panigale 1100 V4 Speciale the around IoM TT course in about 18:40 for an average speed about 121 mph. I say roughly because it is impossible to time the lap correctly since it is not a typical get-away, nor lap completion. But it is close enough. It's on YouTube in two parts, part 1 being here: https://www.youtube.com/watch?v=OYaSG_IoAXk For a stock bike, that seems pretty impressive. However, Steve Hislop set a 18:39.4 lap on an RC30, or the Honda VFR750R as it was also known, back in 1989. So what do you think? Is it impressive that 30 years later, an 1100cc stock machine on road tyres can match a 750cc modified street bike on slicks from the 80s, or would you have expected more from the development? As a comparison, the New Era 750 record around Phillip Island was set by Scott Campbell on a Honda RC30 in 2016 with a time of 1:40.719. The production Superbike lap record was set by Wayne Maxwell in 2018 in a Yamaha R1 with a time of 1:32.224.
  1. Load more activity
×
×
  • Create New...