29 January 2009

bright biking

Most common reasons for biking without lights:
  1. Forgot to bring dismountable battery light.
  2. Dismountable battery light was stolen.
  3. Empty batteries.
  4. Light bulb died.
  5. Broken cable or other disruption of electricity from a dynamo to the lights.
Number 4 is becoming a non-issue now, since most lights are LED powered.
Number 1 to 3 can easily be avoided by having a fixed, dynamo-powered light.

Now, some inventors came up with a simple solution for number 5: integrate the dynamo and lamp. The product is called Reelight and here's a nice review of it. I personally oppose flashing lights on vehicles (except emergency ones), but Reelight has developed their product so far that the newest version can also produce a steady light. Progress here you come!

In related news, there's a fun gimmick which could make your bike ride even safer: self-illuminated pedals. Looks good, but I have no idea how much it really does for safety. I hope it doesn't have such a negative, traffic-disturbing effect as those flash-lights do.

PS: Of course, you can also solve the transmission problem by simply using robust 2$ two-core cables on your bike, instead of 0.20$ single-core plus frame built-to-break wires.

Update: Judging from other reviews the reelight doesn't seem bright enough to actually show you the way. That would mean you still need a dynamo if you safely want to avoid potholes and other crap on the street.  I decided a pair and test them myself (on a friend's bike), as soon as I am back to Canada.

26 January 2009

multiple-geared bikes: a pragmatic general comparison

The simplest and "robust like a Mercedes" gearing solution for urban poke-around is a 3-gear hub. As simple as a single-speed bike, but with much faster starts at the green light! Those hubs have a development of around 186%, which is sufficient for many purposes. (As example, I thook my 3-geared, 16 inch wheeled Brompton on a tour to the Lyons mountains.) If such a thing fits your purpose, don't read any further! Unfortunately those hubs are not very available in North America, Dahon being one of the few bike makers you use them. Check out their "Curve 3D" or the "Vitesse 3D" (the latter one, not marketed in North America, unfortunately). As for Europe, no need to mention any particular brands and models, since hub-gears are widely available (even Dahon has more models using them).

For people who are riding longer distances or hilly areas, a solution with 7 to 9 gears and a development of around 300% will be absolutely sufficient. This can be a hub (three brands offer several models) or a (rear) dérailleur transmission. In both cases you get a linear sequence of gears shifted with a single level and the fastest one is about three times faster than the slowest ones. This covers uphill as well as tailwind situations.

In my opinion, double dérailleurs (front and rear), double hubs (hub gears plus Schlumpf-drive), dual drive (a gear hub plus a cassette) and high-end hubs (Rohloff 12 speed) are a thing for cycling freaks and dorks. Especially the double dérailleur is usually underused (small gears not used by most people), because people just use their mountain bike in the city or on easy to medium trails. Also, the double dérailleur is more complex to shift, and has a lot more wear and tear.

Here's some calculations showing what you really get from a bike that claims to be "21 gears" (or more). Lets call the three chainwheels A, B, C (A being the most-teeth/fastest) and the seven sprockets 1 to 7 (1 being the least-teeth/fastest). Then, the combinations A6, A7 and C1, C2 can't be used because the chain would run diagonally and have too much slack (C1/C2) or too much tension (A6/A7). Besides that, those four transmission ratios are reduplicated by other combinations (which ones depends on the exact tooth counts) and therefore useless.
This leaves us with 17 usable gears, but in reality most people would only use 9 of them and here's why. The fastest gear is A1, from there one shifts down to A2, then A3, then B3, then B4, then B5, then C5, then C6, and finally the slowest gear C7. In short, the number of gears that most people use is only 7+3-1 instead of 7*3. (The same holds for 9+3-1=11 on nominally "27-gear" bikes.) The reason is that most people only use one lever for shifting a gear, and never two, as would be necessary to shift from A3 to B2, for example. What's more, most people wouldn't even know which of A3 or B2 is the faster gear!
The double hub and dual drive (though they have other advantages) have the same problem of messed up gear order.

My advice: even if a bike with double dérailleur looks attractive, don't buy it! A 300% transmission with either a gear-hub or single dérailleur will be the better choice. More convenient, simpler, and more durable. As a very practical extra, those solutions allow the use of a chain guard (the most sporty-looking version just on the chain wheel, as on Dahon's "Speed"). The hub gear even allows a fully covered chain which reduces your maintenance-interval from every couple weeks to every couple years. (Frankly, I wanted to clean Speedy's chain after one year, including rides to slashy snow, but their just was no dirt on the chain!) I think that Dahon's "Vitesse 7HG" (that one available in North America) will fit such a fully-covering chain-guard. It's a matter of ten minutes of mounting this chain guard to saving hours of maintenance later!

Those 7 to 9 gear hubs and derailleurs are widely available in North America (and in Europe anyway) and so I don't need to mention any particular model. As a final remark: the combination Dahon Speed (or any P-range trekking model) plus hub-gears is not available anywhere, so you'd have to build your own, if you wanted to imitate my Speedy. But anyway you'd have to do that because of Dahon's half-hearted dynamo-lights. (See upcoming post.)

24 January 2009

pirates vs. bike mechanics -- Bunny's story

First of all: my new bicycle (see recent post) finally has a name!
Now, the story of what happened in the bike shop when I went there again for fixes and fine-tuning.
To better understand what happened, please recall the scene from Pirates of the Caribbean - Dead Man's Chest where William Turner challenges Davy Jones for a dice game proposing a life of servitude as his stake and asking for "the key" as Jones'. Of course, young Bill looses, but he still achieves his purpose: Jones shows the key and now Bill know where it is stored.

Okay, here's what happened in a bike shop in Taipei, threehundred years later. I asked for a readjustment of my headset which the shop owner does with the wrong tool (my heart is bleeding!) and with unsatisfactory results. But at least I do now know how the handle post is to be dismounted! This confirms my expectation without myself having to take a risk.
But the stories goes further, because I also asked to increase the gear ratio. Shop man's first reply was of course that I should have bought a more expensive bike with more gears in the first place. I explained, that I do not want more gears, but just want higher gears. (Same story which happened with Speedy, only on a different level of quality.) Anyway we discussed a number of options and in the end he offered me a piece of hardware which had a smallest sprocket with 13 teeth instead of 14. The piece looked used and it was not Shimano. He later told me that it's from a racing bike. I suppose he meant a big racing bike, not some other folder. This clarified my other question: apparently the Dahon rear hub takes any standard free wheel with sprockets. This means that I could put one on myself. In Toronto, I would probably find such a piece at the Bike Pirates or UofT Bike Chain...
In any case, I got the information!

I am still horrified when I think how the bike shop man tried to adjust the headset without loosening the counter nut first. Maybe I misunderstood that, but it seems he just wanted to avoid taking the seatpost off first. I will investigate this further before I make any adjustments myself.

So, finally, it looks like Bunny got all her tuning for commissioning done. I am satisfied with her so far and soon we are going to go for more rides. Let's get up early tomorrow morning! And starting from tomorrow I will also look for potential buyers who appreciate her strenghts...

23 January 2009

Built to Last

When I read the publicity text on the the flyer that came with my new bike, there was one section of writing which touched me so much, that tears came into my eyes.
I had to think of my now almost eighteen year old bike which I got as an (already quite tall) child for my birthday. During the time that I rode it, I had to replace many parts due to ordinary wear and tear (tires, chain wheels and the chain) or which were obsoleted (dynamo, lights, rack). But the bike is my bike: the frame and all the bearings are unchanged. With all the updates, it rides better than a new one. This is "built to last".

Here's Dahon's text (from their web page which is slightly different than the flyer):
So many of the products that are manufactured today are disposable. We're appalled by the poor quality of so many of the products that we see. We remember when children's toys were sturdy enough to be handed down from child to child. Now, many of the toys out there are lucky to last a few months of use before falling apart. That's why our landfills are filling up so rapidly and why we are seeing so many shortages in raw materials. A lot of the bicycles built today fall into the disposable category - low quality bearings, poorly coated materials that rust quickly, and corner cutting everywhere add up to a product that won't last more than a year or two. We want our bikes to be part of the solution, not part of the problem and that's why we've made a commitment to using higher quality materials and components that last longer. Details like stainless steel spokes, sealed hubs and bearings, stainless steel frame latches, chromeplastic fenders that will never rust, and anodized finishes on aluminum components are found on every one of our bikes, even the most economic models. We get emails almost every day from customers that are still riding bikes that are 10 or 15 years old and that's the way we like it.
(Highlighting is mine.)
Unfortunately, most of the bikes sold nowadays (that is also most of the bikes _bought_ nowadays) are simply rubbish. Just look at this one.
People are staring at me when I tell them how much my bikes cost. But figure what's cheaper: a $200 bike that lasts for two seasons or a $2000 bike that lasts for a life time. (Hint: I plan to live longer than 20 years.) As for the interpretation of "life time": Dahon grants a life-long warranty on all Dahon-made frame components and here "life" means that of the bike, not yours. I suspect that in a post-nuclear, post-petrol world, people are still riding their great-grandparents Dahon bicycles. Incidentally in Taipei, besides all the shiny new bikes (and, unfortunately, cars) there is the occasional old Dahon parked somewhere, a design that looks more than 20 years old, but those bikes are still rolling along, despite being subject to Taipei's acid rain.

Here's a hint, should you ever need a cheap bike. In that case you are probably better off with a second hand one, that is still in good shape, than with a soon-to-be rubbish new one. Having survived it's first couple seasons, chances are that the veteran bike is actually of some quality and that will not only last you long, but that you can also sell it for a comparable price to what you paid in the first place. A better deal indeed!

Every cent spent on rubbish vehicles is wasted money. Every hundred bucks spent in quality are a life-time investment.

This post is dedicated to David Hon, Thomas Lösch, and Speedy, my love.

my new (temporary) bike

It hurts my heart a little bit to call this bike "temporary" since I bought it new, had it customized in the shop, already started tuning it, and still think about more tuning. I bought it with the intention to sell it before I leave Taiwan, with the time that has already past and some slack for my visit to China, that's less than three months of having this bike. But in spite of all this, I already love the bike.

As I mentioned on my Taipei blog, it's a Dahon Eco 3, the cheapest Dahon model sold in Taiwan, so cheap in fact, that they don't sell it in Western countries. Except Australia it seems, where I found this page with specs which you might want to check out. (The Taiwanese model is different from the Australian one is explained below.)

What I think of the bike:
  • it's a Dahon frame which I think is the same as the one used for more expensive Dahon bikes. The same goes for the folding mechanism. No other bike I saw here has the same easy folding levers! Also, the bike with fully extend seatpost is just high enough for my size, I can stretch my legs fully (which I can't on other bikes) and the handlebars can also be adjusted to be quite high. The general design of the frame (including wheelbase and position of the bottom bracket; i.e. the pedals) is already worth some money!
  • Despite being a great ride, it is not too heavy either (which again not every other bike can claim).
  • It has V-brakes with metal levers which really look like good quality.
  • The routing of the wires is simple, clean and looks well thought-out.
  • The gear shift is from a Shimano, but looks like the cheapest ones they make. I have to ride it more to see how good it is, but I don't expect any troubles from it.
  • The Taiwanese model did not have fenders, so I ordered extra ones and the only thing which the shop could offer me were stick-on fenders which are not just an invitation for thieves, but also a little short for my taste. I hope that I won't get dirty in the rain!
  • I also ordered an extra rack which is a little small, but looks cute and came with a rubber band to hold things and is still big enough to hold my Ortlieb bag. Which, by the way, I own and enjoy since almost ten years now! The bag only fits on one side, since it would hit the derailleur on the other. When I put the bag as far back as possible I still sometimes scratch it with the heel of my shoe, but that's not much different from Speedy and its high quality made-in-Switzerland rack.
  • Aside: The seat post seems to be the only part which is just the same as for Speedy.
  • The handlebars are a really light construction, directly welded onto the part of the handlepost which can be adjust in height, sliding inside the bottom part of the handlepost. The quick-release cleat which holds the two together gave me a bit of trouble. It has a rubber part on the inside between the two parts of the handle post. The upper part pivoted sideways on this rubber and so the handlebars had a little horizontal play. (No play in the steering though, that was ok.) So I tightened the cleat a bit. Later, while riding the upper part would slide down slowly. When I brought it up again, I tightened the cleat more. And later even more. Now, it doesn't slide down any more, but it's still pivoting a little bit.
  • The headset seems to be a little to tight. I have to investigate this. Update: I think it is too tight and should be loosened a little. The Eco seems to have this infamous scheme where the headset is held by the same bolt which also holds the handle post in place. I didn't want to play too much with this, so I will try to have it done by the shop tomorrow. (Already looking forward to explain this in Chinese. I hope the dealer will not claim that it has to be this way, because then it's really gonna be hard to explain!)
  • The lever for the handle post hinge was not properly adjusted. It was too loose and the entire handle post did pivot a little on the hinge. Also it made some small noise when riding over uneven ground. This was easy to fix, but it shouldn't be necessary in the first place. Ironically the bike has a sticker which says "Before riding, have it adjusted by a professional dealer." Now I have to learn how to express discontentment in Chinese, while still being very polite, cheerful, and optimistic.
  • I haven't actually folded the bike yet and will not do so soon, since it already got quite dirty during today's ride and I'd like to clean it a bit before folding. Update: at least I tried out both folding hinges and I also folded the pedals for parking in our stair case.
  • The spokes seem tight enough, but the wheels are uneven by a margin of one millimetre. I know that with one hour of work per wheel, I could get this straight up to less than half a millimetre (as I have on my other bikes). A better bike mechanic could do it faster, of course, but this level of quality is just not included in such a low price. Probably it's not included with any factory-made bike. I am just playing with the thought of fine-tuning those wheels. Such an intimate involvement would make it really hard to give the bike away when I am done here...
  • Update: I downloaded some manuals from Dahon's website and those manuals are also a sign of overall quality. Safety issues and basic maintenance is well explained. There is also a very detailed manual from Shimano for their derailleur and shifter. At least some technical information which I have been missing before. Dahon also has online support and forums both of which low-end brands do not have.
The bike still needs a name, it will probably be an English one, because Chinese names never seem to mean what I thought they would.

Keep you posted on further tunings and our great adventures on Formosa island!

6 January 2009

English spelling reform, part two

Just a hilarious poem to convince people that something should be done.

Update: this version of the poem published by the Spelling Society gives proper credit to the author, tells the story of the work and gives a more complete version.