They don't. But if you're prepared to wait there's still some AP50s, SS50s, Garellis, Fantics and so on available for keener prices. If only the manufacturers could see how these little motorbikes were key in the biking boom, they'd still be making sports mopeds rather than stupid little scooters. They'll suss it one day I guess.
Absolutely agree with you on the sports mopeds! Though not the AP50, SS50 (Ugh!) but the Fantic, Garelli, Gilera bikes were really interesting especially the Trail versions. I would go for: Gilera 50 Trail Yamaha DT/RD any Kwacker KH250/400 Suzuki GT250/380/550 And oh dear the RG500 of course I sold my beauty for £5K in 2006 (owned from 86) but it would probably be £10k+ by now. I so miss that sound! If only I'd had a spare garage.
I've seen a few immaculate Moped classics at the H Cafe but not that one! It was just the maddest moped ever made (but I would die if I had to ride it!)
Either: Buy something that was reasonably expensive,and therefore quite rare from the get-go. But as the relatively affluent no longer see it as desirable,there's often a time when prices are very low. At the moment,750SS/900 fit into this category IMO Or buy something that was popular,affordable when new,but has lost value to the extent that no-one looks after it. These things will become rare as many won't survive the neglect of multiple careless DIY Owners. And when the many previous owners become older and more affluent,they want to relive their past with the things they previously owned,hence the increase in prices Thats why cheap Cortinas/FS1e's no longer exist.
With the general biking market moving away from sports bikes I'm surprised most are only listing sports bikes as investments. I think a BMW R1150GS Adventure would be a good bet. The first of the popular adventure bikes and still a bit too common to be rising. By buying now prices are low but it's already hard to find a lowish mileage one - if you could find a 20,000 miler it'd be "cash in the bank". Also, with the rise in popularity of nakeds I think Buells are worth a punt (only Harley engine ones, not Rotax - and even then not the Ulysses). Prices are already firming up. I'd go for the later petrol in frame models as they're not coming to market much now and would concentrate on the 1200 rather than 883. Early 900 Monsters would be worth a go (thought I should mention one for the home team given this is a Ducati forum) as long as completely standard, low mileage and red. They are a bike that seems too cheap at the moment for the first proper modern naked i.e. designed to be a cool bike rather than a commuter. All of them need using IMHO, but by investing in a few bikes you can spread the mileage so that none of them get overused. However, outperforming servicing, insurance, tax etc. in value may be harder unless investing in more expensive stuff.