The seriel number of my "new" Stuart Turner flat twin is 8174 but the plate is missing & I have no date for it. The other one I have is just 450 units away being S/N 7724.
Nick Highfield has sought out serial numbers of extant examples and these are the ones we know of 19/09/1927 - s/n 7077. 29/09/1927 - s/n 7100. Mine is 19/12/35 - s/n 7724 and now 8174 & I'd guess at 1938. 03/07/1939 - s/n
8265. 17/08/1939 - s/n 8298. 19/04/1943 - s/n 28460. Nick thinks the apparent jump in numbers was a change in the numbering system, not a huge jump in production because of The Unpleasantness. Other ST models were numbered in the 8,000 range & the addition of a 2 is simply to avoid confusion. That's what we think, anyway!
There are now seven known to us & it surprises me that they are emerging from the woodwork steadily now. Two years ago they were virtually unknown.
I've removed 8174 from its bed plate & also the steel framing - some of it cleverly reproduced in copper - made a starting handle for it & started it without any trouble or stripping apart from the plugs needing cleaning. It runs well enough, but briefly & had a nasty clanking sound. It sounds like something hitting the flywheel/fan, but I've had the barrels & heads off to be certain & there is no discernable wear in big ends, mains, pistons, rings or bore. One bore is so good, the piston took some removing & came out with an audible PLOP! I'll get it back together tomorrow, but I need to buy some Hylomar first.
One thing, in common with the other that I have, the aluminium has suffered badly from corrosion (especially around studs and bolts) & I notice this one too is treated with etching primer to make the paint (no traces left) stick better to the ali. Although it's been in the workshop two days now, the metal was still damp & water oozed out of the gap between base plate & sump. I'm suspicious that a chemical reaction is pulling water out of the air & depositing it on the surface & thus the casting is always damp. I used a gas torch to free off the mounting bolts & the damp fled away from the torch. As I came up to the house, I noticed the surface was wet again & my workshop is as dry as a bone, bare steel not rusting in thirty years. The other ST flat twin I've wire brushed & is now dull polished aluminium. It sits there with no dampness upon the surface.
The comments of wiser heads is eagerly sought ;o))
Time for food & TV