+ Click to Enlarge BASIC FUN: The Yamaha XTZ125 is an unpretentious and unintimidating commuter/playbike. Pictures: DAVE ABRAHAMS

January 5, 2004
By Dave Abrahams

Yamaha's wholly-owned Brazilian subsidiary is best known as the last refuge of the RD350 – the infamous "Elsie" was built there as late as 1995 – but most of its products are robust, rather basic commuter bikes specially tuned to run on petrol laced with methanol distilled from the country's second-biggest crop, sugar cane.

Think about it, Cyril, can you imagine running your bike on cane spirit?

This is the first Brazilian Yamaha 4-stroke I've ridden, but it lives up (or down!) to the standards set by its 'stroker compatriots – there's no electric foot, the choke lever is right there on the carburettor and you check the revs by ear - change gears when the valves bounce, china.

The 123.7cc single has but one camshaft, two valves and one straightforward Mikuni slide carb to help it crank out 9.3kW at a claimed 8000rpm, with a slightly less anaemic 11.7Nm of torque at 6500 revs.

Without a rev-counter it's difficult to quantify the motor's power characteristics but I got the best results by short-shifting before the point where the engine began to vibrate and sound a little stressed. The bike pulls up to 80km/h quite smartly; then the curve flattens out but if you have still air and a long straight it will wind up to a genuine 119km/h - not bad considering I weigh more than the bike does!

The slightest headwind or uphill will knock 10km/h off that, however; I soon found that the bike comfortably maintains a 90km/h cruise under most conditions, so for four days I went everywhere at sixteener pace, enjoying the scenery you never even see, at full tilt boogie on sports machinery.

It's a while since I've had to kick-start a bike, but the XTZ presented no problems, although it usually needed the choke and half a dozen prods to wake it up. The choke lever is down on the carb; you can't see it from the saddle while riding, so it's wise to teach your fingers exactly where it is before you ride the bike in the early morning traffic – otherwise you'll ride all the way to work (or school or college) with the choke on.

The clutch is initially grabby, then a little slack and finally goes home suddenly; it's an odd, two stage take-up which takes a little getting used to but it remains consistent, hot or cold, as does the gear-shift, which is positive but distinctly notchy. There's also some driveline lash, not unexpected on a duel-purpose layout with its long final drive chain

I soon found that upshifts – other than from first to second - are distinctly slicker without the clutch, so that's the way I rode the little Yammie.

Low-tech chassis

This unpretentious prime mover (I hesitate to call a 9kW single a powerplant!) lives in an equally low-tech frame, an open cradle structure with a single down-tube, welded up from steel tubing and sheet steel pressings. The rectangular swing-arm is also steel, even though both it and the frame are painted silver so as to look like fashionable light alloy components.

The suspension is also very straightforward with conventional cartridge forks devoid of adjustment in front and what Yamaha calls "Active Monocross" at the back. It seems to be nothing more complex than the original monoshock set-up, with the bottom of the single shock pivoted on the swing-arm and the top anchored high up on the frame, at the rear end of the backbone.

The rear shock is adjustable for preload but we didn't bother; even with two adults on board the rear suspension refused to bottom out on decent tar roads. Two-up the front end dives sharply under hard braking but remains stable until the front end starts to push on; the Brazilian-made Pirelli knobblies are more of a limiting factor here than the damping.

Riding solo on tar the suspension is firm but not harsh, a good compromise between the initial suppleness required for bundu-bashing and the taut control necessary to keep a very light bike in line at highway speeds. The bike remains stable up to its top speed in a straight line, with a slight tendency to shake its head on long sweepers - easily controlled if you resist the temptation to hold onto the 'bars like grim death.

The XTZ's brakes are also firmly third-world, a drum brake on the rear and a twin-pot floating calliper in front, which seems a little silly from the company that pioneered the use of opposed-piston brakes on streetbikes. But the inherent lightness and compact dimensions of the simpler calliper make sense on a 103kg commuter/playbike, where its additional maintenance demands and tendency to fade under stress are less of an issue.

Certainly I couldn't work it hard enough to provoke any misbehaviour, on or off the road, and the direct feedback from the front disc tells you exactly where the wheel is and what it's doing.

Getting down and dirty

I played truant from the usual chores for a couple of hours one Sunday morning and took the Brazilian baby playing in a local green area - through mud, shallow ponds and thick pampas grass, across rocky dumping grounds and hard-packed flats. It handled everything with aplomb until I got it stuck in a hole – then I could have used a bit more poke to help pull it out by its bootstraps.

A couple of times I had to rev it hard and slip the clutch unmercifully to get it moving but the bike never complained, although under these circumstances it stalls easily and you're back to kicking. Luckily it has no problems with hot starts - unlike a certain enduro machine from the same stable that broke my foot one Christmas Eve.

Keep it rolling, however, and pick your way carefully on trails you don't know (advice that applies to any off-roader, really) and the Manaus mosquito will get you there in fine if unhurried style.

I had just one hairy moment; I hit a patch of deep, soft sand going just too fast to steer and too slow to prevent the bike from digging in. Almost instantly it began to fishtail wildly as the back wheel tried to overtake the front and I had visions of being spat off by this 9kW moped in tackies.

But it's a four-stoke, isn't it, and when I instinctively did exactly the wrong thing and shut the throttle, the back wheel practically stopped turning and the bike straightened out as it sank rim-deep into the sand. A quick dab down into second and I was on my way again, suitably chastened.

That's the joy of the XTZ125; it'll teach you off-road riding techniques without punishing you for your mistakes – a very special attribute in a bike meant to be ridden by inexperienced sixteen-year-olds convinced of their own immortality.

Practical styling

The rest of it is styled out of the budget parts bin; the plastics are uncomplicated but the two faux radiator shields jutting forward from the 11-litre fuel tank (the XTZ is air-cooled and has no radiator) give it very much the look of the latest 'crossers, as do the enduro-style faceplate and long narrow saddle.

Practical touches are everywhere, though; a pair of sturdy grab rails are bolted to the rear sub-frame, as are tubular brackets for the rear footpegs. The instruments, no more than a speedo and the basic warning lights, are big and easy to read, tucked behind the plastic face-plate, and the forks are neatly if unfashionably gaitered. The only real omission is a sump guard.

It's no road rocket – which to a lot of mums will be a point in its favour – but as a commuter and a training tool for learning the art of dirt-riding, the XTZ125 is right on the mark. It's robust, tolerant of heavy-handed riding (although it apparently doesn't like prolonged over-revving through the gears) and forgiving of inevitable novices' mistakes.

Brazilian teenagers are probably a lot like ours.

Thanks to Caren Sharpen at Linex Yamaha for the loan of the test bike; the XTZ125 costs R18 869.

Click here to use Motoring.co.za's repayments calculator.

Specifications:

Motor: Liquid-cooled four-stroke single.
Capacity: 123.7cc
Bore x stroke: 54 x 54mm.
Valvegear: SOHC with two overhead valves per cylinder.
Compression ratio: 10:1.
Power: 9.3kW @ 8000rpm.
Torque:11.7Nm @ 6500rpm.
Induction:Mikuni UCAL carburettor.
Ignition: CDI electronic.
Starting: Kick.
Transmission: 5-speed constant mesh gearbox with final drive by chain.
Suspension: Conventional Showa cartridge forks at front, monoshock adjustable for preload at rear.
Brakes: 220mm disc with Nissin twin-piston floating calliper at front, 141mm single leading shoe drum brake at rear.
Tyres: Front: 80/90-21 tube type. Rear:110/80-18 tube type.
Wheelbase: 1350mm.
Seat height: 835mm.
Dry weight: 103kg.
Fuel capacity: 11 litres.
Price: R18 869.

Click here to use Motoring.co.za's repayments calculator.