Old vs New Geometry

A chap came in for a fitting last week with a lovely 1990′s steel framed ‘ten speed racer’. It was spotless and had obviously been very well looked after. The non indexed 5 speed shifters were on the downtube and it had a quill stem. I had been thinking about how bike design had changed over recent years and to see this bike ‘close up’ confirmed the conclusions I had come to.

You may think that the single biggest influence affecting bike geometry was the increased use of carbon fibre, but in my opinion, road bike design in the last 20 years has been changed the most by the movement of the shifters from downtube to hoods, coupled with the increasing number of gears.

When the shifters were on the downtubes, we had our hands on the bars tops and drops, moving to the ‘hooks’ when braking or climbing. With the shifters in the hoods, and more frequent gears changes, we prefer our hands to be on the hoods for a much larger proportion of the time.

When riding on the ‘hooks’ this customer’s hands were very uncomfortable, not surprising really given the wrist posture and white knuckles

 

The trouble with just putting the shifters into the hoods was that for a lot of people they were too far away, especially as the ‘reach’ of the bars was typically at least 100mm if not more. This is why we have seen the increased use of ‘compact’ bars with both shorter reach and drop as well as better designed shifters that attempt to spread loads over the whole palms. The position of the shifter has also altered, when they first came out, they tended to reflect the old ‘hooks’ position with sharp angles between bar top and hood skirt. Unfortunately, some people still set them up this way and their hands hurt. Fortunately, most manufacturers now ensure a smooth transition from bar to hood, optimising hand comfort. We have also seen an increase in ‘Sportive’ geometry with shorter top tubes and longer head tubes, but again this is just allowing us to ride on the hoods whereas we used to be on the bar tops.

Mike

BikeDynamics.co.uk

 

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