Kona name their bikes after farts

So I guess it’s only appropriate that I cracked one.

While dismantling the back end to renew the swingarm bearings (which turned out to be completely shot)

Busted Kona after dismantling

Oh noes, what’s this funny little lump in the paint? I ground the paint off to reveal…

Cracked swingarm overview

A nasty little crack 🙁 Oh well, this explains the creaking noises that were coming from the back end last season.

cracked swingarm closeup

I have no idea how this happened. Stinkies are supposed to be tough, and the previous owner didn’t seem like the kind of guy who would huck off his garage roof all day. And I didn’t ride off anything that big, either! This part of the frame seems to be exposed to a lot of bending forces from chain tension, so maybe it just came to the end of its fatigue life.

Or maybe I’m just rad to the edge of sickness.

Error codes of history

-100,000: Come down from the trees? [Yes|No]

-99,999: Are you sure? This operation cannot be undone.

…….

1066: Invalid media in I: (Fatal)

1492: Unexpected “Indians” in atlantic.c

1690: Oppress any Catholic to continue

1861-1865: Slave not responding

1920:  Distiller performed an illegal operation and will be closed.

1939-1945: You must be an administrator to install the Third Reich.

……

2000 and above: Volume “La-Z-Boy” is full. Please delete some of your beer gut and try again.

When a man is tired of tires…

Yes, another gripping blog post about bicycle tires!

First of all, big up the Bontrager Hard Case, a “puncture-proof” tyre for road bikes. I put them on my commuter bike and have had 0 punctures so far, down from an average of 2 per week with the stock tyres.

Second, fat rims need fat tyres! I run Sun Mammoth rims on my Stinky, and Alastair at Wheelcraft persuaded me that it’s OK to run regular sized MTB tyres on them. His “loaf of bread theory” is that the tyre works better sat inside a wide rim like a loaf of bread in a baking tin, than bulging out of a narrow rim like a Starbucks muffin. Well, he’s wrong. I put a 2.5″ Big Earl on the front, in place of the old 2.25″ tyre, and the bike corners so much better it’s unreal. I think the narrower tyre ends up with a flattened tread profile that stops the contact patch from assuming the right shape when you lean into a corner. Like putting a car tyre on your motorbike. It kind of works on the back, but you wouldn’t want it on the front.

Finally, an apology to the Conti Gravity tyre that I bitched about a few posts ago. I got hate mail from someone who lives next door to the Conti factory 😉 I put it on the front of my Inbred and it works great. It’s just a bit wussy to be a back tyre on a freeride bike.

The Stinkpad Saga Part 2.

I did some more research into the “meh” quality of the Stinkpad onboard audio, and it turned out that the sound chip resamples everything internally to 48kHz. The resampling doesn’t seem to cause any bad artifacts, just a slight loss of treble through the anti-alias filter, but that very lack of high end is probably what makes it meh.

So I decided to have one last attempt at getting an audiophile-grade output from old Stinkpad, and if it failed I would throw him out of the window and make do with a single computer. I’ve long been a fan of M-Audio products: I struggled with music production on consumer soundcards for years, until the day I bought a Delta 66, and everything just worked. So I bought a Transit, which is their cheapest, lowest-channel-count USB audio doofer.

Upon installing it to the Stinkpad I got exactly the same snaps and pops as before, at the rate of about 5 per second 🙁 But this time, I noticed that they only happened when the CPU was idle, and loading it up with Winamp’s visualisation thing made them go away. There were no pops from Sound Forge, and indeed I was able to get a bit-for-bit digital copy through the Transit’s optical I/O to my MP3 player and back. (I have an IHP-120 running Rockbox that has digital I/O and can record and playback uncompressed, so I could test everything by dubbing a test file from the laptop to the IHP-120 and back, and subtracting the result from the original.)

This was a promising result that made it worth investigating more. I assumed that the problem was due to some sort of power management system that was shutting the CPU off when it was idle, and maybe taking a bit too long to power it up again, so that the USB audio stream ran dry. And now the heartwarming bit, the Thinkpad 600X might be 10 years old, but IBM/Lenovo still support it! I was able to download a power management driver compatible with XP from their site. This added a tab to XP’s Power Properties dialog, with options to disable CPU and PCI bus power management. I disabled the CPU power management, and the audio troubles were utterly gone, with the machine running considerably faster as a bonus.

Of course, in computing you never fix one problem without introducing three new ones. The CPU fan now runs full speed all the time, and I expect the battery will now last about 5 minutes while the laptop will get hot enough to fry eggs 🙁 There doesn’t seem to be any way of having this CPU power management “On for battery power but off for AC”, either. Maybe there was a driver to make that happen in Windows 98, but it wouldn’t work in XP.

Oh well, I guess this is what I get for bringing a vintage tractor on the information superhighway.

I smell stinkpad…

I’m currently trying to kick my computer collecting habit, as there’s only room for so many of the things in my flat. My plan is to get down to two machines: one small, low-powered one that can be left on all the time, for things like playing MP3s and internet radio, and running BitTorrent, and a big fast machine crammed with noisy fans to use for my digital audio experiments. The role of the low-powered machine used to be filled by Linosaur, my Linux server, but it’s currently down after a failed attempt to fit it into a smaller case. (That’s “down” as in dismantled in a cardboard box in my mum and dad’s garage. No, it doesn’t respond to pings.)

Hence, I decided that the Stinkpad should take its place. This is an old IBM Thinkpad 600E that refuses to die. It was made at IBM’s plant in Greenock, so it has some typically Scottish quirks such as headbutting you on errors instead of beeping. I upgraded the memory and hard drive, but I can’t do anything about the slow-ass 500MHz CPU. However in this application, the slowness isn’t a problem, as long as it can run uTorrent and Winamp.

The problem I had was that it wouldn’t even do that, since I upgraded it to XP. The onboard audio tended to stutter whenever the machine was loaded, and any external soundcards I tried just popped and stuttered even worse. I tried all sorts of things, messing with settings, disabling all the XP eye candy, but it made no difference.

That is, until I went into the Device Manager and noticed that my hard drive was running in PIO mode! Like it was 1987 again! 🙂 (For non-tech readers, PIO is an old, obsolete way of communicating between hard drive and computer, which is very slow and wastes CPU power. Any half-decent machine can use “DMA” mode which shifts the data faster, and lets the CPU get on with something else in the meantime.)

All attempts to make it go into DMA mode failed, until I found this helpful script. After the mandatory reboot, the stuttering was gone, and as a bonus, the Stinkpad felt about 10 times faster. It must have been stuck in PIO mode for ages, maybe even since the day I installed XP. Who knows why it happened, I’ll just hope it doesn’t do it again.

It now performs its role better than Linosaur did. Since it’s Windows, I can listen to the BBC IPlayer (powered by Windows Media, which makes it pretty off-limits for Linux.) I get really good sound quality using a Roland UA-1EX USB sound dongle, with Otachan’s ASIO plugin for Winamp to bypass all the kernel mixer and resampling gubbins built into Windows. (for media played through Winamp at least…) No I don’t! it worked once and then started snapping and popping 🙁

Neatest of all, using TCPMP it gives decent full-screen playback of MP4 movies, something Linosaur always struggled to do since it had no screen at all 🙂 I first tried TCPMP as a player for my palmtop, and it worked so well on that, I thought I’d try the desktop version too.

All in all, I think this is pretty good meh for a 10 year old laptop running XP.

I <3 Soma FM

Lately I’ve been listening to Soma FM a lot. I especially like their Groove Salad channel. They play Boards of Canada all the time, but that’s not necessarily a bad thing.

Anyway, their 128k MP3 stream has pretty decent quality – I guess it’s technically the same as a DAB radio station – and it plays on just about anything. Winamp on my PC, with its Delta 1010 hooked up to the stereo, no problem. Linosaur, my Linux server, was a little trickier, but once I figured out the stream URL, I pasted it into phpMP and saved it as a playlist, and off it went. I have a LCD and keypad hooked up to linosaur using LCDproc and a modified version of lcd-stuff, and I can play stuff from that.

Perhaps the coolest thing is that it plays on my Pocket PC (an old Ipaq hx4700) using GSPlayer. When you visit Soma FM’s page, it downloads a Winamp playlist onto your machine to start playback. That contains several streams, I guess as backup if some of them are down. I just got this groovesalad.pls file and copied it onto my PDA’s memory card. (I prefer to keep stuff on a card, since my hx4700 crashes and wipes its RAM with monotonous regularity.) When I run GSPlayer (which I also keep on the card to save reinstalling every 2 weeks) the playlist can be opened and the fat beats begin.

So, if I do this, and dangle my DSL modem/router out of the window, I can listen in the back yard while washing my bike. I’m off to do that now 🙂

Have your pi, and eat it too

I don’t remember when it was that I first heard of pi. I was home schooled, but my mum and dad said that all attempts to get me interested in maths failed, and this was one reason why they finally sent me to school aged nine. So maybe my dad explained the concept of pi while we were plodding through the Leadhills looking for dippers to ring. Or maybe it was one of a succession of long-suffering teachers and lecturers. Whoever it was, I’m grateful, because pi is a lovely number.

Now, anyone who knows anything about maths knows that pi is the circumference of a circle divided by its diameter, and that it has a value of 3.1415927 or thereabouts. If you know nothing about maths, just imagine a circular lake with a bridge right over the middle. It’ll be 3.14… times further to walk all the way round the lake than to walk over the bridge.

If you’re a real math geek, you’ll also know that pi is an irrational number, which means that it has more digits after the decimal point than anyone can ever imagine or calculate, and hence it can never be written exactly. If you’re a really serious math geek, you may even know a piem or two. And if you’re totally hardcore, you’ll object that pi could have any value you like in a non-Euclidean geometry. But I’ve never met any math geek hardcore enough that they could tell me what the meaning of pi is. Why should an everyday thing like a circle manifest itself in mathematics as a number so big and exotic that nobody can ever know it exactly?

Maybe a discussion of where circles come from would help. The circle, and its 3-D cousin the sphere, appear in nature because they are the most effective way of enclosing space. If you have to make a bag to keep stuff in, as Nature did when evolving eggs and tomatoes, then a spherical shape bags you the most “stuff” for a given amount of eggshell or tomato skin. And, since Nature abhors waste, these objects turn out spherical. Well, eggs aren’t quite spherical, but luckily for chickens, they’re not quite tetrahedrons either. So maybe pi is just a mathematical way of saying that Nature doesn’t do corners. And if it’s irrational because it’s natural, then the endless series of decimals is no more worrying than bugs in your organic lettuce.

Then again, the state of Arkansas recently redefined it to 3.0 exactly. If they’d chosen 4, maybe eggs would have turned cubical overnight and chickens would have really had something to squawk about.

Or then again, maybe pi doesn’t have any meaning whatever. I struggled with math at university because I insisted on believing that it had some kind of correspondence with reality, and looking for physical metaphors to understand it intuitively. The laws of physics can be described as mathematical equations, and the behaviour of some physical systems can be predicted by mathematics, so it’s easy to believe that the universe is somehow made out of mathematics, and learning it will unlock all the mysteries of the universe. But in the end, the universe is made out of universe, and maths is just a game that mathematicians play.

Níl i mata, a shaoi, eolaíocht nó feidhm. (“Wise one, mathematics has neither science nor use.”) – an Irish piem giving pi to 7 decimal places