> Dennis, > > I've made a break though of sorts in the multi-speed fixed gear > area with the SRAM P-5 to three speed fixed conversion. This > builds on my previous work with the T-3, and creates a hub very > similar in function to the Sturmey Archer ASC, but with wider > ratios. It offers direct (1:1) and two reductions of .78 and .63, > respectively. A new version of the fixing block locks the output > of the pinion carrier to the hubshell, and is installed in place of > the pawl carrier. This provides a drop-in conversion, and requires > no welding or grinding to either the hubshell or any internal > parts. Slack is minimal, about the same as the old ASC. > > I've geared it 52-16, which gives gears of 85, 67, and 54. Top > gear is direct, and second and low are the reductions available > from the two planetary gear sets inside the hub. The second gear, > at 67 gear inches, is a comfortable ratio for city streets or just > spinning on the flats. The 54 inch low is pretty handy for hills > and also makes skidding easy. The 85 incher is for descents, > tailwinds, or chasing down your friends on geared bikes. It could > also be geared around 48-18, to give 70, 55, and 42, for easier > climbing in areas with steeper hills. > > The stock twist grip shifter mounts to a road bar via a Hubbub > adapter. Original gear 1 is still low, positions 2 and 3 give > second, and positions 4 and 5 give direct drive (1:1). > > The rest of the bike is pretty much stock Pista. I had a local > leather place make me some leather strips for wrapping the bars > (Paraguay has LOTS of cows) to match the honey Brooks, and tied it > off with natural hemp twine. > > I'll put together a tech article soon with details of the hub gear > conversion. Inquiries and orders for the fixing block can be sent > to glw1954@yahoo.com. > > Cheers! > > Graham Webster > > >