Change bicycle crank

Last winter during the two month long ice age I fell of the bike. I got stuck with the front wheel on a hiden tram track (under the snow I missed it). The fall was quite hard and one of the pedal crank arms on the Kronan got bent.
Since during the summer I've been taking Luísa on the Batavus and the Kronan was "ridable" I let it linger for a long time... and after much procastination and "planning" I decided to order online and replace the cranks myself.

There are several tutorials on the net (one here), and what is definetely needed in a crank removal tool and special recessed nut wrench, all the other tools are common workshop tools.
First remove the plastic cap hidding the bolt, then use the special recessed bolt wrench and remove this bolt.


The insert the crank removal tool in the crank nut and turn the extractor bolt, this will slowly move the crank arm out of the axel.


Then just remove the crank arm and remove the pedal (just the crank arm was bent, the pedal was unharmed).


Remove the pedal with a wrench.


Put in the new crank arm, screw in the fixing bolt and the old pedal, repeat for the other side and voila!

And now I'm ready for the harsh weather with the Kronan again...

Luísa is two!

Luísa is two today...


We picked her up early from the daycare... she was not "thrilled" when we woke her up in the middle of her afternoon nap...
Well, we managed her to wave (reluctantly) after a few seconds... (Only after she insisted on getting on the bike :-)

New Year's resolutions...

This year is coming to an end and this will be my last post (this year). I didn't post as many times as I wanted (I planned once a week, I'm close to once every two weeks), but that's the way life goes.
Most projects are "work in progress", so these are in plan for next year:

1. in the mini68k I wanted to finish a working gdb-stub before advancing to the CP/M-68K code. I finally managed to make it work, but there were some bumps in the way. The way ahead is not without it's perils, to use gdb and CP/M at the same time I might need an extra serial port for which I have no breadboard space. I'll need to draw the schematics, possibly make a PCB, make the SDCard interface work and then port CP/M to it;
2. in the mini85 I wandered off in some hardware questions (casing, with a floppy or without, processor speed, with DMA, cheap DMA, video, expansion, connectors, front panel, size of RAM, SD Card, SD Card removable, Flash or Eprom, serial ports, parallel port...). I'll need to settle down on the hardware, draw schematics, make PCB, fit in a case and close it;
3. in the Solarlight project I still want to fit it neatly on top of my Pepper pot and to tune some more code, also add a larger heatsink for the LED. I also plan to do a new SMD PCB and bake the components in a SMD oven. Further, I'd like to build a bike light with the same circuit but no solar charger. I'll need to get the final schematic, draw the SMD PCB for solarlight and bikelight and make the code linux-buildable and downloadable;
4. in the SBC6120 project I'll need to decide on how to fit everything inside the box and fix the harddisk to the PCB, also design the front panel, back panel and connectors.
5. in the home monitoring project I'll need to rewrite the code for the new light sensor and adjust the pachube data to it.

I don't think I'll run out of electronics projects for next year, but if just in case I do, I have to change a pedal crank on my Kronan (got bent on a recent fall on the snow) and I'm waiting for some studded tires :-) , read some more books and try to reduce a bit the coffee intake...

Mending Jeans

I bike to work regularly, even during winter. As a result my jeans wear off often, every time in the same place, let's call it "the saddle area". I used to take the jeans back home and ask mum to do it. She would just go to her "work room" power up her good old sewing machine and get it done in no time.


Since we decided last year to buy a sewing machine, I thought I could try and do it myself. It is very easy and hardly noticeable once the patch is made.
You will need a pair of jeans to fix, a jeans patch a bit bigger than the hole (+2cm, 1 inch) and thread.


There's a trick about the thread (thanks mum), use grey or light grey thread. Using blue thread, even if it's the same colour as the jeans will produce a noticeable patch.


Place the patch on the inside of the jeans and secure it with pins, take care to stretch both the jeans and the patch.


Load the top thread with the grey coloured thread (the under carrier is not so important), select a wide zig-zag stitch (5mm width) and reduce the length (advance) to 1 to 2mm (a bit like the bottom right stitch of figure 2 here).
Lock both fabrics under the zig-zag presser foot starting from 2cm/1 inch outside the hole to cover, sew until 2cm/1 inch the hole end. Repeat in reverse.


When you reach the place where you started, move the needle to the top most position, release the feet, move the fabrics 5mm (about the width of the stitch) to the side, press the feet and repeat until the hole is covered.


Here is the patch finished. The good news are it is hardly noticeable, the bad news are, that usually if you do this in one leg, chances are the other leg's fabric will also fail in a few weeks.

Accidents happen... hoppefully only in 2009

I apparently only write about my bike(s) when something bad happens, well today I was ran over by a car...
I was comming from Pavillonengracht through the Stille Veerkade, night had just fallen, I was returning home after a small "shop tour" looking for agendas for 2010, a small computer mouse and a couple of pen refills.

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I had my lights on, as I remember turning them on when leaving the last shop. I had the priority and I saw the car waiting, I thought he saw me... Unfortunately he did not! The car hit me on the pedals, lost my balance and fell to the floor on my side and hit the head. I was amazed on how fast the general public reacted, immediately someone came to me, told me not to move and called emergency service. They started talking to me too fast for me to understand, I asked if they could speak in English and they all changed to English. They asked the usual questions, "if I had lost conscience?, pain in the neck?, if I thought I had anything broken?", "No,No,No" I said... the police arrived checked how I was, followed in a few minutes by the ambulance. By then I was pretty sure that I had nothing very serious, but I could have a broken rib.
In the ambulance a quick check was made, nothing broken just some bruises... Blood pressure and pulse a bit high (I think I was in shock), but nothing serious apparently.
Coming out of the ambulance, the police was waiting for ID check and note taking of the accident.
The man that hit me was also a bit nervous, I greeted him told him that I was OK, we exchanged addresses and contacts for the insurance and parted ways. I'll have the bike at the repair shop next week.
My sincere thanks to everyone that helped me, the casual people that called the police and came to help me, the Haaglanden politie and the Emergency Service in the ambulance.
The Kronan was not left in a good shape, she had taken most of the hit... we'll see how she'll recover from this one...



.... Update, after taking the bike to the incompetent bike shop under Den Haag Centraal Station, on the first ride I noticed the frame was bent... really bad... I'm not very hopeful that the bike can be repaired :-( ...

Kronan lighting

My Kronan is a simple bike with simple "extras", the headlamp is a filament bulb powered a dynamo, a simple LED tail light and a Kronan bycicle bell.

Since I installed the front cargo fork I had to reroute the power from the dynamo to the alternative location of the headlamp (on the other fork arm).


I noticed that there is a light sensor and when I leave the bike in a shed or I stop the tail light turns off after some time. But my current problem is that sometimes during a long route the light turns permanently off. I had to open the box and see!!

Apparently there's a transistor, a light sensor (top, back of the PCB), a red LED (transparent), a capacitor (bottom, back of the PCB) and an embedded IC. The IC has a blob of plastic (next to the capacitor) over it so no chance of knowing what it is. My current possible culprits are:
the battery connection that has oxidized or the light sensor is not correctly placed and the sensor is influenced by the LED.
Currently I just opened the box, cleaned the contacts and straightened the sensor but I doubt that was the last time I had this problem.

I also had some time so I decided to check if I had any noticeable chain stretch, I folded a new one over the current one while breaking and checked for any big difference after 10 links... so far, everything looks similar (i.e. no noticeable stretch).
I found more sites (here, here, and even in Wikipedia) giving instructions on how to check for chain stretch.

Adjusting the Rear Axel

From the title of the blog, I bet you would expect more bike postings... Here is the second one...
Two weeks ago, when starting the rear Axel moved. If the Axel is not securely fastened when you're really pushing the pedal, the Axel can shift forward (on the crank and chain side) and the wheel becomes bocked by the frame, like in the picture below.

Fixing it is quite straight forward, unscrew the axel, hold the wheel in the center while stretching the chain, and progressively securely fasten the Axel. A good guide on Bikes can be found here, although the author of said site prefers direct drive, my Kronan is a "Single speed" with a "Coaster Break".

My new bike wheels

A couple of months ago we had an accident with the bike. Ana was siting on the back, I was driving through Bezuidenhoutsweg when a (stupid) Girl hit us coming from the side. None of us was really hurt, but the front wheel of my kronan was slightly bent. I ordered a new set of front and back wheels, inner tube, and tires and last Saturday I prepared and fitted them. My bike is black and from the picture you might notice that the rims are painted in blue.... Yes, they were cheaper in blue, now my bike looks like it came out of a Bauhaus design shed. Since my last set of tires I started using "Slime TM" to prevent fixing the inner tube every time I have a puncture (quite common). It's really great, once you have a small puncture, just fill the tire back again until the leak stops, and you're up and running. I also changed the chain (good policy once you change the rear hub).