Classic Bike Guide -Real rides, real riders

A pretty twin set

With Matchless twins featuring this month, it seemed only right to include this eye-catching combination. Eye-catching because it’s finished in that beautiful two-tone red and white which carries over onto the matching Monza sidecar. It's a delight to just look at a well balanced, cosmetically appealing outfit. However, to reach this stage wasn’t plain sailing as owner Don Noble explained. “A friend had a G12. I liked its performance and wanted to upgrade from my A7. I was thinking of changing when this Matchless turned up so I bought what became an expensive mistake.”

Parking up at home he asked his wife to see his purchase only to find a large puddle of oil underneath it. On checking, almost everything was loose. First serious fault was the gearbox. Don said. “I was riding around the arena at a steam fair when I noticed the kickstart lever moving down as I was riding. The layshaft bearing had failed, so I completely overhauled the gearbox. Then the rims started to rust badly, so after removing the front wheel, I found the taper roller bearings were shot, which meant a complete replacement kit – spindle as well – you can't just change the bearings. The rear rim wasn't quite as bad, but it will need replacing soon.”

As the repair bill starting to go up, so did the big end bearings. Don continues, “Returning from the 2008 Engineerium Run, the engine sounded like it had a bloke with a little hammer in there. I stripped the engine and found I could move the rods up and down on the crank.”

That was bad news as G12 cranks are practically unobtainable. He took it to Hartland Engineering to be reground, but it turned out to be too far gone. “I phoned all the AMC suppliers, but they're like gold dust. So I had no choice but to have it metal sprayed by Hartlands and then reground. They also rebored the barrels and I fitted new pistons, rings and new big ends, the mains were OK.”

On completing the rebuild, the engine smoked, so he removed the heads again and fitted new valves and guides, which cured it. The primary drive was fitted with a new chain and the clutch has probably had some heavy duty springs fitted to cope with the chair. Brakes were OK.

He rode the G12 solo, then a pal found a Tribsa with a sidecar attached but didn't want the chair, so mentioned it to Don. “I’d never thought about a sidecar, but I made an offer and all of a sudden I'd bought a sidecar!” he said.

The Monza is stylish, a glass fibre body on a tubular steel chassis and features hydraulically damped leading link suspension. The body needed work to restore it to an acceptable standard. “I stripped it,” said Don “and found the bottom rotten, so I rebuilt that with new glass fibre, then filled, rubbed down and spray painted the whole body.  That was over £100 in paint alone.”

The metalwork was better than the body, as was the suspension, needing no more than cleaning and painting, which Don finished in traditional gloss black. There are still some oil leaks to sort on the Matchless, “I've had the heads and barrels off several times now, trying different gaskets, silicon sealant and so on, but I'm not winning with the base gasket leaks. I've been told I'm not using enough silicon but you have to be careful with that stuff and not block oilways.”

He's also unsuccessfully tried new studs and nuts, but hopes new, thicker gaskets might work. It's possibly crankcase breathing at fault and an investigation is imminent.

Despite these problems, he said, “I actually like it! It's got all the power I need and find it just right for pulling the chair.”

One bright spot was the wiring, a previous owner had rewired it well. The ignition is by coil and distributor and uses points instead of an electronic system. “It starts OK so I'm not worried about changing,” said Don.

He did change the front tyre, from a Speedmaster to an SM, “Better suited for the sidecar.  Since fitted, the steering is much better, I'm not fighting it any more.”

Fitting the Monza to the Matchless wasn’t just a case of bolting it on and hoping; there's a number of different factors to take into account.

Don recalled, “A club-mate, Mick Droupin, lent me a book with a chapter on fitting a sidecar. It gave all the measurements and descriptions on how to fit the chair properly. I feel I've got it about right as I can take a hand off the bars and still steer easily. A lot of fittings came with the sidecar, but they weren't for the Matchless, so another pal gave me a box of fittings, which proved useful. I had to make up one or two brackets, but as an ex-sheet metal worker that wasn't very difficult.”

One other useful addition was the luggage rack. “I cut it about to make it fit and then took it along to the platers to be rechromed. When I collected, they only charged me half the original quote as they weren't able to polish right into all the various angles. That didn't bother me and I was happy with the price.”

AMC's 500cc G9 twin introduced in 1949, which featured swinging arm rear suspension as standard, an industry first. Another design feature was to support the cast iron crankshaft with a third centre bearing.

The G9 evolved into the short lived 600cc G11, followed by the 650cc G12 and its variations. The twins culminated in the hybrid G15 Norton models, production ceased in 1967. Equivalent AJS models were produced simultaneously, which, following the mix and match policies, resulted in confusion over which make the bikes were supposed to be! No such problems here, Don's G12 is pure Matchless; it wasn't until 1964 that things changed with the introduction of Norton forks and brakes. Improvement? What say you?

If you've not tried a combo before, have a go to compare the ride with a solo; I guarantee you'll look at sidecar pilots with a renewed respect.

Don volunteered passenger duties. Starting was easy enough – once we'd sorted out a flooded carb – just a smooth swing of the kickstart induced life.

Once under way, the gearbox proved to be light and precise in use; not so the clutch, at least at first, due to those heavy springs.

I couldn't actually pull the lever all the way in, but that didn't matter, as long as I could just 'break the plates', the gear change was as sweet as a nut.

Don was right about the torque; the bike pulled away with ease and thundered up through the gears without a hitch. I leveled off at the 40mph limit – grateful that it wasn't 60mph – and settled into a comfortable cruise for a mile or two before turning left into a country lane. Plenty of bends here to practice on and the Matchless didn't disappoint, pulling Don, the Monza and myself without complaint, even at low revs in higher gears.

Vibration was negligible and the brakes worked well, stopping us quickly without grabbing or fading. The outfit was well set up, allowing me to relax my grip on the bars without any ill effects on the steering, something I was certainly pleased
to experience.

I swapped places with Don to get a passenger's view of the Monza; it's not just a good looking chair, but comfortable too. There was enough legroom for my 5ft 10in frame and an independently sprung wheel provided good protection. A Perspex screen kept the wind off my face and my back was supported by a padded rest.

I can't conclude without returning to the outfit's appearance, as it attracted favourable attention wherever we went; the two tone never failing to catch the eye. The bull nosed Monza also has a look of the Boeing Stratocruiser flown by BOAC in the 50s – and they were built as luxury long rangers, an image that sits well with this Matchless sidecar outfit.