BUYERS’ GUIDE: LIGHTWEIGHT AMC SINGLES
Largely ignored by generations of classic fans, it could be time for AJS and Matchless lightweight 250 and 350 singles to enjoy their time in the sun
The under-rated Matchless and AJS 250s and 350s appraised
Think of AMC singles and the chances are something like a Matchless G80 will spring to mind. Nothing wrong with that. They’re fine bikes; as, too, are the 350cc G3L and their AJS counterparts. The so-called heavyweight singles are the stuff of classic legend. But they’re not the only four-stroke single the AMC conglomerate produced. After a long while in the shadows, the once unloved ‘lightweight’ singles are starting to become more appreciated – and sought after. Could an AJS Model 14 or 8 – or Matchless G2/G5 suit you?
AMC’S lightweight singles range entered production for the 1958 sales season, with the 248cc
AJS Model 14 Sapphire and the Matchless G2 Monitor (yes, really).
Both bikes were virtually identical apart from the badges and colourschemes. But, while they looked at first glance like thoroughly modern, unit construction, lightweight singles, they were actually a little bit oldfashioned in engineering terms.
For a start, the engine and gearbox weren’t of unit construction. The primary chaincase on the drive side and an all-enveloping alloy cover on the timing neatly concealed the fact that they were separate, and an oil tank integral with the crankcases gave the (false) impression that the engine was a wet-sump design, too. But despite that – and some initial problems with crankpin breakages and premature main bearing failure – the lightweight singles evolved into fairly reliable and competent machines. A number of bottom-end upgrades improved matters and, eventually, a larger crankpin was fitted to the 350cc models and the 1962-on CSR versions of the 250. These can be retro-fitted to earlier 250s using a late-model conrod. CS scrambler models also have the larger crankpin.
The 350s and 1962-on 250CSRS also benefit from a duplex primary drive and the superior Teledraulic forks used on the heavyweight singles range. With a stronger bottom end and a touch more performance, these are probably the ones to go for. Top speed for a standard 250 should be around 75mph, with the 350s and 250CSR
models good for 80-85mph – though the factory claimed 90mph for the CSRS. That’s about comparable with the contemporary competition and equates to a comfortable cruising speed of between 55 and 60mph.
The parts situation is fairly good, thanks to the owners club spares scheme and a couple of good, specialist parts suppliers. That, together with still-affordable prices, makes owning and running an AMC lightweight single a practical proposition – and a potentially pleasurable one.
If you don’t fancy heaving a heavyweight twin around so much these days, a 250 Brit single can have a charm all of its own. And, while AMC’S ‘lightweights’ are not exactly what you’d infer from the name – a 250 weighs around 50lb more than a BSA C15 – they’re a whole lot lighter and easier to haul in and out of the shed than a 650.
The years have lent a certain charm to AJS and Matchless lightweight singles, too. They may have looked a touch behind the times when they were launched in 1958 but, 60-plus years on, that’s all forgotten. Now, surviving examples are admired for being reasonably robust, peppy and characterful lightweights. Maybe it’s time for more of us to take a closer look at them...