>After reading Michael's request for recommendations for his "right >frame size," and if I'm interpreting Rivendell's sizing chart >correctly (?), will Michael's pbh clearance above the top tube on a >57cm Hilsen be about 7mm, with a 35mm Pasela? > >At what point, for road and/or country bikes, does pbh clearance >become a safety factor for the rider?
The answer is simple: Standover clearance never is a safety issue even for an only mildly experienced rider. There was a Bicycle Quarterly article on this issue a few years back. Here is a short synopsis. Background: Most of my bikes have marginal or no stand-over clearance. My 9-year-old son's bike doesn't have standover clearance either. My bikes were sized that way to get the handlebars to about 1-2" below the saddle without riser stems, sloping top tubes or huge quills showing. On my son's bike, it's simply a matter of trying to find a lightweight (<30 lb.) kid's bike with a geometry suitable to slow speeds. The bike is too big for him, but he is rectifying this by growing like a beanstalk. (We reduced the reach by replacing the drop bars with cut-down mtb bars, but we couldn't shorten the seat tube.) When you stop a bike, it is very difficult to jump off with both feet. In fact, riders new to toeclips or clipless pedals sometimes fall down because they get _zero_ feet on the ground. Once you realize that you put only one foot down when you stop, standover clearance no longer is an issue. When you put one foot down, you also have to lean the bike to prevent it from falling (the bike and your leg on the ground form a triangle), which lowers the top tube a lot. You also move your pelvis to the side, and off the "dangerous" top tube. If your top tube is _way_ too high, you will simply lean the bike a little further when you stop. My son did fall once when he first rode his new bike. However, your private parts never are in danger. After you have put one foot down, you can put a second foot down, and some riders do. If you don't have standover clearance, your foot will not reach the ground. Since you already are standing and bracing yourself and your bike with one leg, you will not fall. Off-road, the "two feet down" situation is best avoided. In Simon Burney's original edition of "Cyclocross", there is a lovely photo of a rider straddling his bike after having failed to ride up a steep hill. The caption reads something like "This rider is trapped - can't get going, can't dismount. He should have dismounted before his momentum was lost." As I said, even my son, whose saddle at first was as low as the seatpost would go, with the center section of the sloping top tube almost at saddle level, never hurt his private parts from lack of standover clearance, and he is _not_ an expert cyclist. One exception is starting on a tandem. If you like to have the stoker put both feet on the pedals, it is useful to straddle the bike. You can do this with marginal standover clearance, as you won't jump onto the tandem. From my experience, standover clearance is not a safety issue. The CPSC recommendation is one of many questionable ones. It appears that they even requested a lip on a Campagnolo front derailleur to prevent people getting hurt by the cage. Right next to the front derailleur is a chainring with super-sharp teeth, so it's hard to see how the straight front derailleur cage makes a bike more dangerous... Something that can kill you - and almost did kill a friend on one of my bikes once - is toe overlap. The CPSC is silent on that, and most experienced riders probably can deal with it in most situations. Jan Heine Editor Bicycle Quarterly 140 Lakeside Ave #C Seattle WA 98122 http://www.vintagebicyclepress.com --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "RBW Owners Bunch" group. To post to this group, send email to rbw-owners-bunch@googlegroups.com To unsubscribe from this group, send email to rbw-owners-bunch+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/rbw-owners-bunch?hl=en -~----------~----~----~----~------~----~------~--~---
