While organizing my workbench, this made it into my hands. It’s a Jim Blackburn SB 1 Stop Block. Does the image or name help you determine it’s intended use? (I won’t run a contest as my name the BMW 850 owner contest was a resounding failure with a perfect response rate of zero–was the contest too hard or doesn’t anyone want to read Marjorie Morningstar?).
Anyway, when I bought the SB-1 from a box of bicycle bits years ago its use was immediately apparent to me. Still, I can imagine a few heads being scratched. Two are for sale on eBay just now, and the pictures of the packaging from that listing clears things up. The SB-1 was produced to help you keep the bicycle upright when parked. Jim Blackburn was making accessories at a time bicycle touring was a big(ger) deal. Every bicycle would appreciate being parked with an SB-1, so why do I mention touring? Unloaded bicycles are easy enough to reliably park by leaning them against things. Heavily loaded touring bicycles are much harder to keep upright (the extra weight gives gravity a trump card).
What about a kickstand? While great for city bikes, they are not optimal for touring. Kickstands weigh a bit and aren’t so good at keeping heavily loaded bicycles upright. One leggers would be next to worthless, allowing your bike to come down more often than not. Two leggers weigh even more and require a fair amount of care to use reliably (a light touch or even a gust of wind could nudge a bicycle to the ground).
A Rhode Gear Flickstand was one nice solution (a solution I used on a few bikes in the 80s and 90s). A couple of those are for sale at Bicycle Classics (an interesting eBay store that is also selling the SB-1). The Flickstand shares with the SB-1 the benefit of stopping the front wheel, but the Flickstand also holds the front wheel straight. Very effective and light, but kind of ugly. Serious tourists probably get over ugly pretty quickly, but looking at the band of plastic always bugged me. I should be clear–while my heart yearns to tour, and I have bicycles and accessories sufficient to outfit a small touring group, I have only done one overnighter and that was as a teen. Big sigh, but that’s me–all gear, no go.
How about a toe clip strap or some other adjustable strap wrapped around the downtube and through the front rim. A bit of a pain, but effective and free. Do people do this?
Unlike the Flickstand, the SB-1 didn’t need to be installed. Just put in place when needed. If you didn’t want to lose it when it was not in use, you could loop it around the brake cable and even clip the back of the block onto your cable. Ingenious and elegant. If I ever tour, I mean when I someday tour, I will certainly have my SB-1 along. I can’t wait! Today’s mileage will be more in the order of three or so miles and the bicycle I will take out will have a kickstand. The SB-1 will go back in the drawer for now.
Enjoy your day.