Recent content by Jim Rogers

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...

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...

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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...

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...

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...

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...

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...

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...

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...

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...

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...

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."

@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...

:)