Thursday, December 01, 2011

Bicycle Geometry

They’ve stolen my very comfortable bike a few months ago. Having problems with my back (herniated discs) it was the only bike I could ride with no pain or any side affects.

So the task is t find a bike whcih would be exactly the same in geometry what my bike was. Why my stolen bike is so unique? Because it had a seat tube angle of around 71°. I have browsed through tons of web pages of bike manufacturers but in 95% the frame geometries use a standard 73°+/-0,5° seat tube angle.

I then luckily captured a TV series on the Discovery Channel, where Mark Beaumont cycled through the World and later Americas. Meanwhile I was watching the episodes I just realised that the bike he is using has a very flat seat tube angle. I made screnshots of his bike from the TV and finally found that he has a KOGA bicycle.

I then searched for the KOGA’s and found that they have exactly the same bike frame what I need. These bikes are the KOGA Randonneur and KOGA Traveller (not the World Traveller), because these have the same 71°seat tube angle.

More importantly I’ve found that KOGA is the ONLY bike manufacturer which decreases the seat tube angle when moving to larger frame sizes, other manufacturers usually leave the same seat tube angle constant regardless of the frame size.

So what’s the issue? The issue is that a KOGA bike cost a lot, they are very expensive. My bike worth of 50.000HUF or £140 or €163 ,while a KOGA costs £1.799 or €1.999. This is more then 10 times more of the value of my stolen bike!!!

I can not afford to spend such an amount of money to buy a new bike so I either give up bicycling forever or have to start spare money in the upcoming years.

However because of my back problems it was a very good tool to exercise my back muscles so it was not only about the bicycling but more about my health!!