All: Am enjoying the good input on BB drop vs. BB height. Here's a few track frameset numbers I have for comparison. Please compare and then we'll discuss. Got these at the shop today. All frame sizes center to top. Measure drop by running a line between front and rear axle centers and measure up vertically from BB spindle to axle line. '55 (my) Rickert Motorpace bike, 1-3/8" drop, 165 cranks, 56cm '04 Fuji, 2" drop , 170 cranks, 58cm '03 Waterford, 2-1/4" drop, 165 cranks, 54cm '05 Orbea, 2-5/16" drop, 165 cranks, 56cm '63 (my) Rickert, 2-5/16" drop, 165 cranks, 54cm '58 Paramount, 2-3/8" drop, 165 cranks, 58cm '05 Orbea, 2-3/8" drop, 167.5 cranks, 56cm '37 (dad's)Durkopp, 2-3/8" drop, 165 cranks, 50cm '20's BSA lug, ? builder, 2-5/8" drop, 165 cranks, 53cm '62 Rickert, 2-3/4 " drop,165 cranks, 59cm There seems to be a trend here in both old and new. I think the reason the riders today think of BB height is that it's easier as a concept. All the frame builders I ever knew always built and measured drop. Dale and the others that refer to drop have it technically more correct in my book, as it gives the more accurate and constant dimension. All of you have it right when you compare track angle and size plus equipment by comparing bikes and how to get around the track at what speed today vs. yesterday. What you didn't hit upon which is the whole key to the essence here is the rider's ability, tire traction, and track surface, plus the rider's bike and equipment dimensions. That's what determines how you're to stay up there and at what speed. One will be able to do 12mph, another 15, and others 18 or whatever before sliding down with identical equipment on the same track A good rider should be able to "feel" how close his pedal is to the track and how fast or slow to go before slipping. I suspect many of today's riders want shallower drops so they can ride longer cranks. I think today's riders in general don't have quite the pedal motion, can push bigger gears with the newer lighter equipment and don't have quite the bike handling adeptness common years ago, and like stated the shallower drop bikes are not quite as stable. You'd be surprised at how quick and adroit one can handle a bike with 2-3/8 drop + or - on a 55 degree track. Europeans have have larger indoor tracks in general, 200 to 250 meters, with some small halls having shorter tracks.The American tracks were built in smaller halls years ago and were mostly about 10 laps or about 150 meters with 50/55 degree banking. The European tracks are 45 degree on average and rated for 50mph. This is what the UCI wants as the world standard. Smaller tracks must be built steeper to keep the riders from going over the top at speed. I could keep writing but it would become book size too soon. Ted Ernst Palos Verdes Estates, CA
> What is the normal BB height clearance on a track bike, so it could be
> ridden on the steepest velodrome? Where is it measured from?
>
> Phil Scott