I have got a report that these two types of rear deraileurs have the same mechanical advantage:
- Shimano Dyna-Sys (which are marketed only as “10-speed”)
- SRAM E.S.P (which are marketed only as “9-speed”

Both take 35mm of cable to go over the whole cassette. Picture shows SRAM X.9 and Shimano XT, but any other derailleurs of the mentioned types would be interchangeable.
This means that either one can be replaced with another (provided that it can handle your biggest cog). I have not verified this myself. Remember that “SRAM 10-speed” deraileurs have different mechanical advantage, as do “Shimano 9-speed” ones, and there are no other pairs which are not designed for each other but work.
Maybe not a really useful finding in practice, but certainly an interesting one.
In August 2010, I made a fast 4-day cycling and bike-carrying trip over northeast Norway. Varanger peninsula, one of real “ends of the world”, is almost encircled by roads, the gap is “just” some 20 km. Here is the map, with the blue track following the roads where I was riding on my bike, and the red track showing the part where the bike was riding on me:

Report with photos here. I’m wondering how is it possible that I’ve been to that region already three times and I’m ready to select it for my vacation trip once again.

In Finland, most trains allow transportation of bicycles, but the fastest “Pendolino” trains do not.
Recently I traveled with my MTB, and Pendolino was the only feasible option (it was the first morning train, the next one arrived already too late). The only way was to partially disassemble and pack the bike so that it becomes normal luggage.

Packed bike in the room
§ Read the rest of this entry…
Spring is coming to our corner. I skied on the Finnish Gulf today, and it might feel like it was last time this year. Steady +5 daily without negatives nightly deteriorates the sea ice.
The picture shows some of my recorded rides. I did not record the shorter ones. Even if the ice skiing season is over (which is a pity), it was a perfect one!

Sure, sometimes a picture can be worth a thousand words. Sure, not always (try for example to express this phrase with a picture). I enjoy nice visualizations… but this time I could not resist to laugh at a failed attempt to draw a picture which would be worth several words, or even just one word
Right, how would you picture “carbohydrate”?
The scan of a chocolate bar wrap shows its nutritional information. OK, I can guess that picture “kcal” in a circle stays for calories. Now, make your wild guesses, what’s the meaning of other circles. Practice your imagination and figure out what the designer tried to depict with so visual guides like
. “Right answers” below the cut.
§ Read the rest of this entry…
§ February 15th, 2010 § Filed under IT § 4 Comments
In many cases, it’s easy to track your browsing – thanks to JavaScript which is by default executed in most browsers. For example, any site can figure out did you visit a particular another site or not. Like, find out which social networks you hang in. So far, it was mostly about showing more targeted advertisements.
Nothing bad has happened to me because of this, and one may argue that targeted ads are better than non-targeted. But I do not like the idea of being tracked – and I shut off all web ads anyway with AdBlock. Additionally, I have NoScript always on (and allow sites selectively each time when “some site does not work”).
Today I have been told that there is a way to track me even without JavaScript and tracking images from spyhouse sites. It is demonstrated here:
https://panopticlick.eff.org/
I have quite long “accept-language” header set in my browsers, as I can read web pages in several languages. panopticlick shows that I’m one such user out of about half million (it might be that I’m just the only one with this value of accept-language, who made a check there).
I’m not feeling paranoid because of this. But I’ll be happy to know, is there a way to pass my (complicated
) language preferences without allowing for easy fingerprinting.
We have a beautiful, real winter here in Finland. The weather I just desire: stable negative temperature never creeping to zero, enough snow for any winter fun – about which I may blog more some time later. One of the cool things to do this time of the year is to ski, skate, walk or cycle over the frozen water. For example, last cold (or, better say, just normal) winter of year 2003 we cycled from the Åland archipelago to the continental Finland. When not going this far, I regularly ski around the Suvisaaristo islands next to which I live (recorded route here). Moving over ice is great!
But what if the ice breaks and you fall in the zero degrees cold water?
There is a simple answer: try this before it hits. Your chances to get out alive become higher. Read on for the boring theory and a short report of how I did this recently in a mild -17°C afterwork evening. § Read the rest of this entry…
Vendors of internal gear bicycle hubs naturally give the transmission ratios of own products. But I was always curious how exactly these ratios are obtained, i.e. which planet gears are engaged in which combination and how many teeth each gear has. This information was surprisingly hard to find – in fact, the only vendor who discloses this is Rohloff! It is certainly possible to just disassemble the hub, but, you know, sitting half-day at the computer screen is more attractive nowadays
I have Nexus-7 hub on one of my bikes, and I have “reverse engineered” the exact tooth counts. § Read the rest of this entry…
Many math problems are fascinating. Often they are also difficult, so that only those who have high enough education can understand their beauty. But sometimes a really simple problem – such that anyone with just the elementary school knowledge can solve it – can be quite cute as well. Most elementary school math questions are truly boring, but it’s possible to add some spice to this mass.
1 (I knew this earlier) “Dried cucumbers”:
Cucumber contains 99% of water. A box of cucumbers weighs 100kg. During winter storage, cucumbers dried out so that they now contain only 98% of water. How much does the box weigh now?
2 (I got this today, which inspired me for this post) “Probability for doctors”:
Assume a test for a rare disease (which affects 1 person in a million) is 99.99% accurate. A patient tests positive. What are the probabilities he actually has the disease?
Bicycle mudguards are frequently made shorter than they should have been. I was not able to find a front mudguard which would protect front chainrings from water jets pouring from the front wheel.
So I made my own from a 2mm thick rubber sheet. It is heavy and non-aerodynamic. It is heavy-duty! It makes difference when riding in the rain. It is tested. Highly recommended for bike commuters.
§ July 12th, 2009 § Filed under IT § No Comments
Nokia has released own online maps, “maps.ovi.com”. I have tried this, and found them to be so much inferior to the competitors that I even feel ashamed for its home country (which is now my home country as well). I think in this area Google Maps set the reference, so I’ve done a small comparison of the two. § Read the rest of this entry…
Living in Helsinki region, looking for a company for evening sporty road rides? Come to Vantaankoski (the home mark on the map below) on Tuesdays and Thursdays by 18:00.
What to expect there? § Read the rest of this entry…
§ June 16th, 2009 § Filed under IT § 9 Comments
Has your web site ever been “infected”?
This happened to me today, first time in my life. Hello from go00ogle.net. Below are technical details on what exactly happened, why I did not suffer any damage, and what I recommend to do in order to reduce your own susceptibility. The article is written for a non-technical reader.
§ Read the rest of this entry…
Article at Groklaw.
My random pick:
“If Europe leads the way in this [allowing algorithms to be patented], I expect many Americans would want to emigrate so that they could continue to innovate in peace.”
I want to buy a silent Linux desktop computer. No need to be any “high-end” otherwise.
This turned out to be a nontrivial task. After hours of browsing and listening to advices (thanks to my friends who already gave some!), I see the following options:
§ Read the rest of this entry…
§ May 19th, 2009 § Filed under IT § 2 Comments
Wolfram Research, probably most known for their Mathematica calculation product, has launched an online service which makes various calculations and visualizations for free, and with just a web browser:
http://wolframalpha.com
This project makes me really respect Wolfram. I spent quite some time browsing the examples, almost exclusively from the “mathematics” part, picking like a shy visitor at other areas. Some of my online friends write that “knowledge becomes less of a fashion in our times”. I do not agree a bit. Just look at this product.
§ May 11th, 2009 § Filed under IT § 1 Comment
10 and more years back, when I studied mathematics, I was an active user and promoter of the (La)TeX typesetting system. Since then, I almost did not use it, but kept the warmest memories of this creation “by mathematicians, for mathematicians”. Yesterday… I can’t say I changed my mind, but I’m not so sure any more about my attitude.
I had to remake a one-page document, for which I already had an old LaTeX template source. Edit the source, “make”, and a nice PDF is ready. Well, now the text which I inserted contained the @ sign. And of course (pdf)LaTeX did not compile.
I did not remember what should one do to typeset ‘@’ literally. I certainly remembered it 10 years back, but that’s not the kind of knowledge which stays alive when not used. It took me about 15 minutes to find the answer.
And now I’m not sure whether I shall promote TeX at all. From my viewpoint, this 15 minutes is unacceptably too much for such “problem” (actually, the very fact that this made a problem, is unacceptable in my current view). I expected the first link in Google search to give the solution, but the reality was very far from that. And – unfortunately for the others – I consider myself as a quite experienced (La)TeX user: I followed news:comp.text.tex, created own document classes, which were also used by other people, and so on. I knew well how it works. I knew where to look for documentation, and what kind of documentation I need. And still this thing, which should never be a stumble at all, took me 15 minutes. I can easily imagine that it takes full day from a person new to the TeX world.
Conclusion: sorry, none at the moment…