Mid-April. Gears, front freewheeling, funny bikes, geometry, patch kit

Mid-April. Gears, front freewheeling, funny bikes, geometry, patch kit

 My dog Billie up there on the highest hilltop near Rivendell.

 

It is helpful to know how to enlarge stuff on your screen. On my MacBook Air, it's COM+. Hold down he command key and keep tapping the + key until it's big enough. Sorry is this is insulting to you. 

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This is an interesting article by Margaret Atwood in The Atlantic.

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Mountain bike frame design/geometry, etc.

Skip this if you don't care, and I'd say you have no need to care; but I have a need to share what's going on in my head on the topic.

The earliest modern mountain bikes copied the geometries of the 1939-1941 one-speed paperboy bikes. Schwinns, Columbias, whatever. 

The seat tube angle (relative to the ground) was 68-degrees, and the head tube angle (relative to the ground) was also 68-degrees. It was "68 parallel."

Terminology: A 67-degree head tube is SLACKER" than a 68 and STEEPER than a 66. SLACKER is less vertical, STEEPER is more.  Ordinarily, when a frame's seat and head tube angles are referenced only by their numbers, the seat tube angle comes first. So, 68x67 means the seat tube angle is ____ and the head tube angle is _____.  This isn't a law, it's just the way I've heard it, and is how I'll do it here, if I get into the double-numbers way.

I have two 68x68 bikes: A 1985 Bstone MB-2, and a 1978 frame built by Tom Ritchey, but never painted or labeled "Ritchey." Both ride great, which is the same as "fine." Normal. I (and you) can tell the difference between a 68 head tube and a 72'er (like later Bstones), but there were other differences in those bikes, anyway. Our current Hillibikes have 69.5-deg head tube angles, which, along with the other changes, seem perfect to me and I think everybody who tries them. Getting off track here.

By the mid-late '80s most mainstream mountain bikes were like 71/70 or 72/71, something like that.

CURRENT modern mountain bikes, with front and rear suspension and all, are like 75-76 seat tube angle x 65-66 head tube angles. Here's proof. The fine-print paragraphs are from the online page, it's not me:

 

 

 

The comments about a steeper seat tube angle (or the more forward position it encourages) being more efficient...is fishy. I am guessing that if it were that, then seat tube angles would have been that steep all along, for about 130+ years; but they haven't. 

I also think that if 65-66 degree head tube angles had been so great-feeling, that THAT might have evolved before the late 20-teens, but it didn't.

Look at this bike again:

 

Now, let me say right off the bat if it's not too late for that: I am not as smart as people who don't work or live with me, but only know me by reputation THINK I am. That's a fact, it's not false humility, and I'm OK with it, I make it all work. But even I can tell by looking at the above bike that when you smack a bump or land hard from a jump, the angles will change. They will "normalize" to the 68-degree + range. 

So the question is, would this bike work if it didn't compress? The answer has to be Yes, but how WELL? Most riders on slacker, 71.5-74 degree seat tube angles still shove the saddle all the way back, because it feels good and it offers a few (ugh alert) ergonomic advantages. When you're "sitting slacker," as the pedal is coming over the top of the stroke, you can apply power sooner. When you push down on the pedal, a more rearward position is easier to maintain--compared to a steeper position, which pushes you forward more.  Maybe it's hair-splitting.

What's not hair-splitting is the steepening of the head tube angle when your fork goes bonk!  If your head tube is 69 or steeper, it'll be may compress to 75 or 76 degrees, and that may pitch you over the front wheel. Imagine going off a jump and landing slightly front-wheel first, then having the front end of the bike dive on you. I'd say quit riding stupidly, but the fat is, modern mountain bikes are designed for that, and the suspension accounts for it. 

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A guy in Indonesia came up with this Platypus/Gus combo bike, and must have liked the graphics on the Platypus. Mixed feelings, but no anger. It's a nice-looking bike. I'd ditch the discs, but whatevs, as they say. 

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We're inching forward on the Hobson-Zingo patch kit. Here's the tin in its current state. The contents are all settled. The marginal word on the lid was the second choice, seemed a little "softer" than the original. But for the record, your purchase doesn't support any pro-profanity organizations (ppo). It's just that all the bad stuff going on has raised my personal offensive bar. For the record, I said my first "sh*t!" when I was 20 and missed a strike on a trout I'd been working on for 20 minutes.

There may be a second, even softer version for kids later on. The red copy is my commentary, not gonna be on the tin.

 

Is that too heavy-handed? Probably. The thing is, I find it so satisfying to patch a tube.  It's an act of rebellion, and it prevents waste.

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Friend ride bicycle collector and restorer Ted Trambly brang this bad boy by yesterday. It's a 1980 Schwinn Varsity with an early indexed derailer, a whole block of fixed (no freewheeling) rear cogs, and the freewheeling in the crank. Bridgestone had its own version of that rear derailer. They called it the Klimatic or Klimactic or something, and you can see is on Disraeli Gears, a super groovy site.

OK, it's here.

Onward with Ted's Varsity: 

 

Here it is in action, kind of.

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 April 7 evening ride, this is Dan-on-Gus not making it up a hill that is a lot harder, in this dusty, rutted condition, than this 20-second video makes it look.

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Here's more on that bikelike device from the last BLAHG.

https://mashable.com/video/infinity-bike-stephen-henrich

Now that I've seen and heard the guy talk, I like it more. I have no need for it, but it's still a clever thing, and the truth (of the matter) is that I have less fear of it replacing regular bikes than I do of modern mountain bikes taking over and replacing them, not because they're more of a long-shot, but because they're just so otherwise different.

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Double or Single or Triple crank?

Here is a guide that isn't horrible. It is worth a look, especially if you're not sure. If you are sure and disagree, cool--but you are riding on a different planet than I am, or maybe just a way different way.

The spreadsheet shouldn't fool you. The numbers are relative. Below the spreadsheet there's an explanation of what the numbers mean, but even that's not important. Higher is harder, lower is easier.

 

 It's on our site, too.

Don't write and tell me about the European "development" method, or even the late & great Sheldon Brown's "gain ratio." This British "gear inches" above is good enough for practical riders, not good enough for physicists or armchairists. But everybody else.

Intermediate gears (btw your hardest and easiest) don't matter, as long as there are several of them.

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We're getting MUSA pants and shorts in soon; and more knickers in a few months. Vince worked really hard with the pattern maker, we've all tried them, and the fit is just how we want them. The knickers, no change from last time. It's been a while since we've had pants and shorts. These will be easy to live, relatively easy to love, and, I think and most importantly, really hard to complain about. Please try them when they come out.

Eventually, and by that I mean later this year and probably within 5 months, we'll have a variety in black, dark tan, medium gray, and a green. They're all military fabrics, made in the USA, and the official military fabric-color names, if you speak that language, are: black, wolf gray, coyote, and ranger green.

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