On Tue, 1 Dec 2009 20:12:03 +0000
Neil Foddering Wrote:
"I suspect that the holes under the bottom bracket on Brit bikes might be drain holes, and that someone has drilled and tapped them for Tecalemit nipples."
Bob Hanson & I had this same discussion some time back regarding both our PX10's. Most of the late 60's early 70's BB at the underside next to the serial# have a hole. Mine happened to have a bolt in it w/ a washer. Bob figured someone had threaded it & put a bolt in it later. I took out the bolt and cleaned it & the washer. This is what I sent to Bob,
'Now, I was ready to yield on the "odd bolt" and assume that it was added later. Measuring the bolt it has about a 5/16" head and was about .188 dia. With 32 threads which would make it a 10-32 bolt. But 5/16 is just under 8 mm and an 8 fits. The threads are not perfect so measurements are iffy. A 5X0.8 is slightly larger than a #10 and the 0.8 pitch works out to 31.7 threads per inch. The clincher is that the hex bolt head has a 6, 8, V & E in a square pattern. This is metric marking. The 6 & 8 are 6.8 which is the class of the bolt & the V E is the maker. Under the bolt is a round (manufactured) washer about 1/8" thick made out of leather so it acts as a sealing gasket. Reaching inside the BB & turning the crank, there is no Crud cage so I would presume someone at the factory thought it needed a drain hole but also a fastener to close it. Seeing another PX-10 on the opposite coast from mine w/ that same bolt suggests that it was a factory item. I would suggest that starting when (?) up until at least 67, the bolt was threaded in the BB.'
Apparently this hole & bolt was used by other manufacturers besides Peugeot. Of course yours would be some English thread unless they were Nervex Pro lugs. Maybe this helps or maybe it muddles it up more.