Gear ratios for Torpedo 2-speed hubs

Figuring your gears is a little tricky with a two-speed hub that shifts by itself. The low gear is 1:1, the high gear is 1:1.36.

The low gear is direct-drive. There’s no fussing; the gear you calculate on Sheldon’s gear calculator is the actual low gear. It is the 1:1 gear.

The high gear is 36% larger. I plugged in larger cog sizes until I got ones about exactly 36% larger. I just noticed that Sheldon’s calculator will let you add fractional cogs!

I’m a double idiot – I just noticed that Sheldon’s gear calculator lets you choose a “Sachs Duomatic / Automatic” hub in the Internal Gears dropdown. This way is a little easier to read, though.

I have a 19t sprocket, and a 22t sprocket. I also have 39, 40 and 42 tooth chainrings I think might work for this project.

The “high gear equivalent” for the 19t is 13.97 (let’s call it a 14). The “high gear equivalent” for the 22t sprocket is 16.18. Again, 16 is plenty close.

With a 19t cog and a 39t chainring, I get a low gear of 56″ and a high of 76″

39
40
42
19t low
56.1 57.5 60.4
36.0 %
high 76.3 78.2 82.1

With a 22t cog and a 42t ring, I get my ideal setup: ¬†52″ low and 71″ high gear.

39 2.6 % 40 5.0 % 42
22t low 48.4 49.7 52.2
36.0 %
high 65.9 67.5 70.9

The Sachs Torpedo 2-speed gives a slightly wider ratio than my double fixed setups that use a 17/21 Surly dingle cog and a four-tooth chainring difference.

New F&S Driving Ring!

A new driving ring for my Sachs Automatic hub!

Last year I tried to get one of these to replace the one I broke. I contacted Jens Hansen at Scheunenfun.de, and got another ring, but it had 10-knobs, instead of 9. That was the first either of us knew that there were two styles.

So… last week I emailed him again, to see if he’d encountered any 9-knob rings, and he had one. He was also willing to take Paypal, which is 10x cheaper than Moneygrams.

Today the part arrived! I was so excited I went ahead and took the hub internals apart and replaced the broken piece. I’ll put up a post about the process in the next couple of days.

So far it looks good – I’m just checking gear inches.

Magical Wheelism’s fantastic machines

ferdinand (li’l red), originally uploaded by magical wheelism – corey todnem.

Magical Wheelism, a Flickr contact of mine, draws the most beautiful bicycle machines. I love the way the drawings look, and I love the ideas behind the concepts (so to speak).

Treadle-powered bikes, bike where you lie prone, bikes with baroque curlicues. Amazing and inspiring. The bikes speak for themselves.

He says he’ll soon have a prototype built. He’s doing the mitering, brazing and painting himself. I think that’s really cool. Fabricating is when tinkering goes pro.

Skate Deck pedals

You can make platform pedals out of recycled skate decks with a saw, a drill and a wood rasp. The platforms clip into clipless pedals, so you can ride your race bike in sneakers.

skate pedals

I’ve been riding these for about 5 years, almost exclusively. They’re the most comfortable pedals I’ve ever ridden, by a wide margin, and very grippy in all conditions except slick mud. Plus, they let you switch your pedals from clip-in to free-pedaling in about four seconds.

Continue reading Skate Deck pedals

Copper wire handlebar twine


Grant Petersen of Rivendell Bicycle Works has popularized “twining and shellacking” bicycle handlebars to finish off the bar tape.

I agree with Grant Petersen most of the time; I’ve gone back to cloth tape, tried a Brooks saddle, and I haven’t ridden clipped-in in two years, even on technical-ish singletrack. I don’t know where my cycling gloves are.

While my bars are an inch above the saddle (but not with a Nitto stem), and I only use electrical tape on black cork bar tape, I don’t like the idea of melted bug parts coating my handlebars, and I think hemp twine looks pretty darn rustic. I’ll stick a feather on my bike any day, but I’m not into the twine look.

I wanted something that made a fancy transition, without going all nature-boy, and I have a spool of copper wire left over from an art project. We put on a kids’ collage festival with decent materials, not egg cartons and toilet paper rolls*.

So… copper wire bar twine.


Make a little loop-y, and place it across the area you’ll wrap. Here I’m covering a half-assed wrap that has lasted for more than a year, but I want a more substantial and clean ending for my bar tape.
You begin wrapping from the open end of the loop, up to, but not over, the closed part.

Wrap, wrap, wrap. The new wire kind of slides in between the old wire windings, and fills them in.
When you get to the end, you poke the free end through, in order to pull the free ends back under the wire.

Pulling the beginning strand pulls the loop and free end back underneath the wire wrap.


I hope you like the look, and consider wrapping your bars with any twiny, wiry material you may find. Brightly insulated phone wire might look cool…

*It’s a crime to give students crappy art materials, even if they’re making trash art.

recycled bar tape


recycled bar tape, originally uploaded by Philip Williamson.

The best part is that the roll on the left, which is from an under-layer across the tops of the bars, is composed of about nine separate short ends of black, yellow and green tape. All the black tape is just short pieces pressed together end-to-end.
It looks like someone working in a bike shop kept the trimmings from several bikes and reused them as padding. I may take them to the Cozine Community Cycle, where they can be used the same way, 15 years later!

Busted pedal


Angelina broke one of her pedals completely off on the way to Winco for groceries. Dang.

She had to push the bike to the store, and then push it home, loaded with groceries. She detoured to stop at Joanne’s to buy supplies for her “Stitch and Boots” Etsy shop – she’s making shoulder/shopping bags that exactly fit in the smaller Wald bike shopping basket.

Her saga reminded me of a story my Anthropology teacher told of an Inuit fishing trip. An ethnologist (a sociologist for non-European non-upper non-middleclass people) set out on a fishing trip with some Eskimos. About a day out, the outboard motor broke, and they paddled over to an ice floe and set up camp. One of the Eskimos found a piece of broken metal, and the leader guy started shaping it to replace the broken gear. After two days, it was ready. They fit the part in, and tried the engine. Failed. The ethnologist is getting really antsy now – they’re running out of food, three days into their three-day fishing trip, and he’s been on a 1/2 acre ice floe for two days watching a guy file metal.
They spent another day on the ice, filing that gear into the right shape. Finally, after a full day of file-file, fit the part, fail to start the engine, they ate the last of their food, filed a little bit more, put the new gear into the engine, and… fired it up! Thank God!
“Finally! We can go home!”

The Inuit looked at him. “Fuck that. We came to fish.”

Moonlight Ride


“Cycling, like sex, is often a solo affair.”

-Pablo Naruda

There’s nothing I love so much as riding alone under a full moon. Tonight I rode the Ross fixed gear out Baker Creek, listening to the babbling of the creek and the rattling of my battery light.
The light didn’t do much illuminating. The moon was much brighter.

When I got fairly far out there, I was surprised that I could spin the rear tire, seated, on a flat road. The road was sparkly with tiny ice crystals, and a little farther up everything was frosty, like it had snowed. When I turned around, I got a little creeped out by the idea of a mountain lion drawing a bead on me. Big stinky prey.
I was pretty careful coming back down the hill, and through the frostiest low section next to the creek. The careful pace became a habit, until I realized I was never going to make it home at that speed, and my thumbs were starting to smart from the cold again. I stopped and listened to an owl hooting for love, then hauled ass home.
Coming by Grenfell Park, I noticed a funny crackly feeling in my beard, and put my hand up to my face. Ice! Ice in my beard! Crazy.

I saw three cars the whole time, and two of them when I was almost back to ‘civilization,’ so they almost didn’t count. In the last mile home I felt a couple of raindrops and hurried on even faster, still being careful to take the corners kind of wide and upright. Apparently I’m still afraid of these 25mm tires!

Custom high-rise stems

My riding yesterday up in the woods showed me just how poor my fitness and bike handling skills have become. Rather than inspire me to ride more, it made me want a custom stem to put the midge drop bars a little higher and closer! Specifically, a 52 x 180 stem like the one illustrated below.

BikeCAD drawing courtesy M. Whitmore

Anyway, instead of riding this morning, I researched custom stems.
Vanilla, Sycip, et al. seem to only make stems for their custom frame orders. MAP cycles (one of my favorite Portland builders) will do a custom $325 stem. Ahearne will do a fillet brazed stem starting at $275.

It looks like the bargainz are the $135 stem ($165 with removable face plate) from Rex Cycles, a possible $175 Rock Lobster (a good match for a Bontrager, I think), and Willits’, $150 Scorcher stem. Wes Williams has made hundreds of super-high-rise stems for exactly this purpose.

New three-speed fixed gear hub

First – I hope people realize that this blog is mostly to write down my ideas so I don’t have to think them up again later, right?
Secondly, it might be useful to someone else who’s thinking along the same lines. Those people are pretty few, but you know who you are.

In that vein, here are my thoughts on the new Sturmey-Archer S3X, an internally-geared three-speed fixed-gear hub. More info, including a schematic, and the proposed colors can be seen on the Sturmey-Archer SunRace blog.


What is it?
A hub-gear that lets you change gears without deraillers, like the old Raleigh 3-speeds. What it doesn’t do is let you coast.

Why would you want that?
Because it’s COOL. I don’t like to coast. I like fixed gear bikes. I like the feel of the drivetrain, I like the challenge of the uphills and the down. I like them.
But if the challenge is so fun, then why a multi-speed fixed gear? Because I have one now, but I have to monkey with the wheel to change gears. I like to ride my bike, and the places I’ve lived have always had hills. Sometimes mountains right in the middle of your ride, and dirt trails are harder to climb than paved roads.

What is that S3X EXACTLY?
It’s a three-speed fixed hub that has a wide gear ratio of Direct Drive (the most efficient, 1:1 gear), 2nd gear at -25% of 1st, and 3rd at -37% of first.

This gear spread is like the old Sturmey-Archer 3-speed AW hubs most people are familiar with. The gears are not like the uber-rare Sturmey-Archer ASC 3-speed fixed gear hub it most resembles otherwise. In 10 years, I’ve known maybe five people on the internet who say they’ve owned one. The AW was one of the longest-lived bike parts ever, possibly one of the longest-lived mechanical items of any kind. The ASC was kind of cultish from the start, and was made for British time trialists (race against the clock on public roads). The ASC had a narrow gear range for optimum efficiency over roads that weren’t that steep, ridden by real hard riders. The AW was made for a wider range of landscape, load and rider.

The people I’ve heard complain on the internet about the “useless” wide gear range of the AW and the new S3X have never backed up their assertions (to my knowledge) with any data about their own multi-speed fixed gear riding.

I think this hub is awesome, and I’m actually going to save up, and possibly sell something to afford one at the $140-$160 pricepoint it’s rumored to have. To see how it meets my needs, I’ll sum them up.

Here’s my multi-speed fixed-gear riding experience:
I’ve had a Rivendell Quickbeam for almost 5 years, and run 42″ to 74″ gears on it. The QB has 40t and 32t chainrings, a 15t and a 17/21 Dingle cog. I also have a Ross touring bike with 40/44 tooth rings and the same Dingle cog for a 70″ and 51″ gear combo.

I’ve pushed my 70″ gear over Sonoma Mountain, and taken it 50 miles through Occidental. I should’ve dropped down to the 32 for Sonoma Mountain, but I wanted to see if I could do it in the big gear. I’ve ridden out to Sweetwater Springs Road in the 72″ gear, dropped down to the 57.6″ gear and rode over it. Multispeed fixed gear is my favorite thing. I also like brakes.
I’ve ridden the 57″ gear up Mt. Tam’s and Mt. Diablo. 57″ is too high to climb Diablo comfortably for me. I’ve offroaded the bejeezus out of the 41″ gear (Surly Dingle cog, another awesomely great invention). Intellectually, the 41″ gear is way way too low, but in practice it’s really really good.
For general riding I like a 70″ gear, but I’ve gone as low as 64″ and as high as 74″ for periods of time.

Given that background, and this upcoming hub, I’m interested in being able to run a a 70″, 52.5″, and 44″ gear, or 84-63-53 to put the normal gear in the middle and have a bigger top end. A stronger rider or a road-only rider may prefer this to the 70″ direct drive, but I’ve been really liking that 42″ climbing gear! Someone who only rides down hills might like a 94-70-60, too. That actually looks pretty good for long flat rides, but I’ve never lived places like that.

For the riding I do, I could be happy for a long time with the 70-52.5-44, or a 72-54-45. No fussing with the wheel at the bottom of the mountain to change gears, no fussing with the fender as the wheel moves back in the dropout to tighten the chain with the smaller chainring.

It looks like the Sturmey Archer S3X will have 12 and 13 tooth cogs, which seem smaller and more wear-prone than bigger ones, but they’d save some weight and minimize the chances of people ripping up the internals with a tiny ring and a big cog.

Real gear choices from the S3X:
My favored 70″ to 72″ top gear could nicely be gotten with any 30 to 34 tooth chainring, and a 40×13 looks pretty nice at 83-63-53. It would be a different set up than I’ve got, but the larger gear would last longer. I’ve got a couple 40t rings, 63″ isn’t so bad for noodling around town, and steep descents would be a lot easier. Maybe too easy.
A 36×12 would give you 81-61-51, and a 40×12 puts out 90-68-57.
44×12
would give you 99-72-62, for all that Southwest Louisiana road riding you do.
All calculations arrived at with Sheldon’s Gear Calculator of course, and rounded for simplicity.

Fantasy gear choices using a Schlumpf:
Tom Shaddox (New Golden Age of Gear Bashing pt. 42) points out that an S3X running 36×15 with a 2009 Schlumpf Speed-drive would be a perfect set of six fixed gears: 113″, 85″, 71″, 65″, 49″ and 40″.

See your own choices:
Here’s my Google Docs spreadsheet of the S3X’s gears. The Excel formulas I used look like this:
A3: desired top gear B3: =A3-(A3*0.25) C3: =A4-(A4*0.37)

helmets and cars

Ever have someone in a car ask you, “where’s your helmet?”

I did once, and she waited until the light changed to do it, too. Which means she was stewing about it for a couple minutes before she had the opportunity to ask a rhetorical question without any repercussions (except my patented “dumbfuck deadman” look that clearly conveys to anyone around that I think you are so stupid you should be dead).

For years after that, I waited for it to happen again, so I could shout, “IN MY PANTS!”

Of course when it did happen again, about two weeks later, on a beautiful green singletrack trail, I was once again too dumbstruck to do anything but stare.

Basically, this isn’t a “newsy” blog post, I just wanted to point out that someone in a CAR, asking me where my helmet is… that’s like a retard with a gun who thinks I should wear a bulletproof vest.

“I don’t have to be careful… I’ve got a gun!

My asthma medication costs $300 a month.

Just for Advair and Singulair, not counting the emergency inhaler at $40 a pop. That made me think about all the cool things I could buy with $300 a month.

  1. Join the Phil Wood wheel-of-the-month club!
  2. Order two custom Rivendells and have the money saved by the time they’re ready.
  3. Buy a sweet LED bike light. Every month. For the rest of my life.
That would be if I had $300 a month that isn’t spent on housing, food, utilities or beer.

I never did find anything cooler than breathing, though.