Tuesday, February 07, 2006

Gearbox continued

Following my post on G-boxx, I saw a gearbox prototype from Hayes showed in Interbike. It is made from a road bike cassette and a very simple derailler that push a pulley across the cassette. The design is good because it is simple stupid, much more simpler than a Rohloff hub. The good part is than standard parts are used here, simplifing replacement, which is a good departure form the geared hub gearboxes. However, this design puts a lot of load on the small chain, leading perhaps to breakage and wear. An overdesigned chain would be welcome here. The compangy said it is open for builders wanting to add the gearbox to their bikes. It is not probable than this design would be light enought for XC bikes, but it might be good for DH ones. The benefits are that


The G-boxx project (http://www.g-boxx.org/) is to create a open-source platform for derailleur-less bicycle. The main objective is to get rid of the breakage prone parts like derailleurs and dished-wheels. A G-boxx bike will typically have a gear box system consiting of either a chain based or a geared hub based system. The result unable a full suspension bike to have a single pivot located in the best spot while still having the main gear situated a the center of the main pivot. It also give the bike a stunning look! The one picutured above is a Nicolai, a mechanical marvel costing about 4000$ frame only. More about Nicolai later. Pictures: www.nicolai.net/

AWD bicycle part 2

Another AWD bicycle design that comes from my home province of Quebec. It's chain driven and it's weight about 45 pounds. The manufacturer said that it is used somewere by soldiers in the desert. The design is not as clean as the one that have been previously discussed. I don't know if this design could handle a full-suspension setup. The point is still if a driving front wheel is needed. Cycling puts so much weight on the rear wheel that gives it a lot of traction. A little bit like front and rear braking, the former being way much more efficient. Picture: manufacturer website: www.chartran.com