Hi Emanuel, The Imperial oval 29mm x 16mm that Reynolds and Altier de la Rive( Vitus) made had thicker walls at the drop out ends around 2.5 mm, although their tapered on OD was smaller, about 11mm as apposed to the Conti oval 27.5mm x 20mm the walls are fairly consistent about 1.2mm + or- .02mm through out and the drop out ends OD 12 to 14mm. Another reason is Reynolds would sell their blades pre raked for various type of rides(up to the builder to chose). Now this is a generalization, the lower or less graceful rake is more bouyant(springy) and makes for a more shock absorbing ride.You are correct, the Imperial oval are harder to rake higher up because of the profile. The Conti oval, with a more graceful rake, looks more flowing and are easier to rake higher. They also distribute more of the stress up the blades to the crown and are great for more agressive rides, plus the old Imperials are hard to come by.
Anthony
Mezzatesta Custom Cycles
Cranberry Twp. PA. 16066
http://www.mezzatestacustomcycles.com
> Question mostly for frame builders or owners of old British frames.
>
> In looking at 531 frames with "old" Continental Oval fork
> blades (i.e. before Reynolds offered blades profiled more like Columbis
> blades), I note that the rake bend is mostly low on the blade, with much
> of the upper blade straight.
>
> With the later New Continental profile (like Columbus), rake bends may
> start much higher, even more than halfway up. Best proponent of this
> gentle gradual bend is Ron Cooper, IMHO.
>
> Is this change in style a simple function of taste, or was the old oval
> blade profile hard to bend higher up vs. the more slender Columbus-type
> oval profile?
>
> Some numbers:
>
> "old" Continental blades = 28.5 x 16.5 or 29 x 16 oval
> New Continental blades = 27.5 x 20 oval
>
> Why care? Because both fork blade profiles are still offered by Reynolds,
> so KOF details...
>
> Emanuel Lowi (who thinks fork blade raking is way kewl)
> Montreal, Quebec
>
>
> __________________________________________________________________
> Looking for the perfect gift? Give the gift of Flickr!
>
> http://www.flickr.com/