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  1. J

    Bicycle Tire Watt Requirements

    Yeah, you've summed it up well. I would say that there is no doubt that there are plenty of examples of newer systems coming out that were either terminally flawed from day 1 or were an ok idea but had a number of false starts in implementation. This was also true throughout the "old days" as...
  2. J

    Bicycle Tire Watt Requirements

    Sorry-- premature post in that last message! Beautiful bikes, and it's seriously cool to have a mix of old and new like that. Don't see the moustache bar and bar ends all that often these days-- I have that set up on a 1989 BS RB-1. What chainrings are you running? They look close in size...
  3. J

    Bicycle Tire Watt Requirements

    Delete
  4. J

    Bicycle Tire Watt Requirements

    Really nice! From 1994-2010, building up 1970's UJB frames (of any name-- Nishiki, Centurion, etc., etc.) was a huge hobby for me, and my whole basement looked like the repair area of a bike shop. Really fun, but I had a major advancement at work and I also moved, so everything bike related...
  5. J

    Bicycle Tire Watt Requirements

    Agree with all that! Agree with this as well but note that I personally do not consider "point belaboring" to be a bad thing. I believe that complex, contentious issues can only be fruitfully addressed through long, deep debate over a long period of time. Some people enjoy the participation...
  6. J

    Bicycle Tire Watt Requirements

    Nearly 50 years for me and definitely agree with all this-- and it's not just tires. I'm mostly a retro-bike kind of guy, but I don't contend that's necessarily better. Pretty much every component on modern bikes in improved over the old stuff, I just happen to like the charm and memories of...
  7. J

    Bicycle Tire Watt Requirements

    Actually, that restatement is clearer, so I do think I understand it better. And that understanding gave me some pause because I had to think about it a bit as it put a different light on my original point. If I could re-summarize and add your point in post #6 that people are (presumably...
  8. J

    Bicycle Tire Watt Requirements

    Yes, it was a question. Because the rest of your post clearly implies that, so I was asking for clarification. I understand, but I'm saying unless you get super-extreme (glass-smooth velodrome or cooled magma flows), that's actually not correct and I provided a link with evidence of that. Do...
  9. J

    Bicycle Tire Watt Requirements

    Ok, yes, in the velodrome where the surface is glass-smooth, the cRR becomes the major contributing factor to tire drag. But are you then going to say that because of that very narrow surface-case, that virtually no one rides on, that all the data are wrong that show wider tires (of equal...
  10. J

    Bicycle Tire Watt Requirements

    That was always the conventional wisdom, but it turned out to not be true. Rolling resistance (as indicated by the dimensionless cRR) turns out to play a very minor role in tire drag and, surprisingly, there turns out to be no tradeoff to using wider tires when desiring higher speeds. Turns...
  11. J

    Bicycle Tire Watt Requirements

    Yes-- true! That's why my numbers don't add up to 100%. Drivetrain + Misc is probably in the 3-5% range. I'm a classic '70s Suntour Super-6 freewheel guy, where I get 6 gears in the same space as the standard 5-gear freewheel and the resulting 120mm dropout spacing. With modern offset spoke...
  12. J

    Bicycle Tire Watt Requirements

    Yes, the extra gravitational force on the heavy guy will tend to allow him to overcome air drag in the way a baseball compares to a whiffle ball. But just to be clear (in case you were making this point), that extra weight is mostly due to the rider-- differences in bicycle weights don't make a...
  13. J

    Bicycle Tire Watt Requirements

    Yes, wind resistance is huge as it goes up by the cube of the speed. So, I should have been more precise with my language, so let me re-frame: "If rolling‑resistance power goes up by 50%, the rider does need to supply 50% more power for that component."
  14. J

    Bicycle Tire Watt Requirements

    @Nessism1 Here are some data to back up my statement that, depending on the tires compared, the difference in absolute watts needed could be up to 50%. They are from Jan Heine's nicely-generated, well-controlled, long-term, highly respected data as published in Bicycle Quarterly over two...
  15. J

    which of these conventional motorcycle oils is best?

    No, it's 50% of absolute watts! As in, a skinny, stiff, high-pressure tire can require 50% more wattage output for the same speed compared to the watts needed for a supple, well-designed casing at that speed. It's a crazy-big difference, yet "skinny tires are faster" was canon for decades...
  16. J

    which of these conventional motorcycle oils is best?

    Hey! I've been patiently waiting for you to engage the examples I've brought up here of bicycle tires and WD-40's efficacy on bicycle/MC chains, both topics you've posted on recently. Figured you'd add some confirmation on those, but here you just left me hanging! (j/k, and FYI, I'm a big...
  17. J

    which of these conventional motorcycle oils is best?

    Ha! Thanks for the injection of a bit of levity. A good reminder that it's probably not the best idea to get too caught up in arguments that don't have much significance-- something I'm often guilty of doing (as you can see!). Good take-- thanks!
  18. J

    which of these conventional motorcycle oils is best?

    I really think this thread needs to end, but if coming to a natural stopping point depends on you getting the point, I think it will go on forever. --I didn't say I had data or theory; I requested data or theory as I've never seen any to support notchy shifting. --I didn't say I picked the...
  19. J

    which of these conventional motorcycle oils is best?

    Thanks, and don't forget that large majorities often start as very small minorities! In this thread I've given two examples (racing bike tire width and relationship between octane rating and fuel efficiency), but there are many, many examples of that. Here's one that everyone can relate to...
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