MZ Mastiff - its bite is definitely worse than its bark

Published Feb 2, 2005

Share

MZ, located at Zchopau in eastern Germany, has been around considerably longer than its better-known compatriot at Spandau but fell on hard times during the Cold War, churning out pre-mix two-strokes of pre-war design and astonishing crudity at laughably low (by Western standards) prices.

With the fall of the Berlin Wall MZ found itself having to catch up on four decades of development almost overnight if it was to stay in business, so the design boffins did the smart thing - they went shopping.

From Yamaha came the XT660 Tenere single-cylinder motor; they got suspension from Marzocchi and WP, brakes from Grimeca and body plastics from off-road aftermarket specialists Acerbis.

They built a very conventional steel-tube backbone frame with a bolted-on square-section sub-frame and fabricated alloy swing-arm, unusual bracketry and some very amateurish exhaust plumbing.

The result was a modular family of commuters, enduro machines and finally the subject of this review, the seriously gnarly Mastiff supermotard.

The driving force is Yamaha's XT660, five-valve single, not the current fuel-injected version but the previous model, famous for using two carburettors on a single-cylinder motor - seriously, Cyril.

On the left of the twin-port cylinder head there's a 26mm Tekei slide carb, to give direct rider input for low and midrange running, with a 35mm, vacuum-operated CV instrument on the right for hard acceleration and top-end running.

It sounds odd but it works: the big-bore single pulls from below 3 000 revs; it gets into its stride at about 4 000 and revs on till well past the power peak at 6 500rpm, with strong primary vibration above 5 500 to tell you it's getting serious now.

Because the two carburettors are designed to react to different stimuli the engine will tolerate sudden changes of throtttle position without jerking or "falling off the power curve" although it tends to run rich on the overrun - more about that later.

It's rated for a conservative 37kW at 6 500 revs, with 57Nm on tap at 5250rpm. In high-speed testing, with me draped over the Mastiff like melted cheese, it took the bike up to 166km/h at 7000rpm, 250 into the red zone - which confirmed my feeling that MZ has shortened the gearing on this model to improve its around-town performance.

Transmission

The clutch is beautifully modulated and takes up consistently, hot or cold - although it became a little juddery for a while after a punishing performance test session.

The five-speed gearbox is conventionally laid out with its three shafts on the horizontal plane and the selector mechanism at the bottom where it gets plenty of lubrication.

As a result it's lighter and slicker than Yamaha's vertically stacked R-series sports bike gearboxes; the shift action is also shorter and more positive that that of the later fuel-injected motor.

Despite the complexity of its induction and valvegear it's not a sophisticated motor; it's clattery, vibrates and is prone to the occasional carburetor stumble, jerking badly at small throttle openings.

However, it's an honest, hard-working big single with a muscular mid-range that's just as much fun blasting out of slow corners on your favourite mountain pass as it is grabbing gaps in the evening gridlock.

Mismatched suspension

For all their illustrious heritage, the suspension components are mismatched; the 45mm leading-axle Marzocchi forks are devoid of adjustment while the WP rear shock is widely tuneable for preload, compression and rebound damping.

Nevertheless, they work perfectly together; its suspension is by far the Mastiff's best feature, soaking up the bumps without excessive nose-dive under hard braking, keeping the wheels in touch with the tar even under the worst circumstances.

I was able to complete my standard bumpy test track at 90 instead of the usual 80km/h, without getting bumped out of the saddle even once.

There was never any patter or chatter, even on the longer, faster sweeps of the "open section" where the shortcomings of the off-road frame geometry began to show up.

Above 140km/h the Mastiff begins to shake its head, especially over bumps; by the time it reaches top speed there's a faint but persistent shimmy even on the smoothest surface.

Although the bike never becomes unstable it always feels unsettled. I soon found that its best cruising speed was just over 130km/h, with the motor at its smoothest and the handlebars dead steady.

Italian brakes

The brakes are by Italian masters Grimeca, with floating callipers at each end. The front brake lacks bite but, thanks to a braided stainless-steel brake hose, it gives more than adequate power and very accurate feedback - just what you need on a short-wheelbase bike with a tendency to pull big stoppies.

The rear brake, also fitted with stainless-steel piping, is much more powerful than you'd expect from its single-piston calliper, capable of locking up the back wheel - even on a dry road.

That's great for supermotard racing where sliding the back wheel around is part of the deal but can be a little nerveracking on the street; I soon learned to treat the brake pedal with respect, especially on wet roads.

The big footprints from the 120/60 front and 150/60 rear Contis gave astonishing levels of grip; with wide bars and a steep steering head angle is quick but predictable and Mastiff can be thrown around with abandon.

On tighter twisties it'll make some supposedly sportier machinery look silly by going deep round the outside and cutting in at the last moment, under perfect control.

Rough-edged plastics

The black plastic fuel tank, blue shrouds, side covers and tailpiece are by Acerbis. They're thickly moulded, tough and durable but made in ill-fitting moulds and not properly cleaned up before assembly.

There's mould flash all along the centre of the tank and (less obtrusively) along the edges of the blue bits. Even though you can understand where they come from, the fact that nobody bothered to clean them up properly - or at all in some cases - leaves a bad first impression.

The switchgear is much better, a close copy of the stuff built by CEV for Honda; the right side has an unusual rotary kill switch below the starter button, but the rest of it is conventional and works predictably.

The instruments - two chrome-podded analogue dials with black faces - are neat and easy to read, as is the neat arrow-shaped panel of warning icons, even if the whole retro set-up looks a little out of place on such a modern machine - supermotards didn't even exist when those clocks were in fashion!

Hard seat

The seat is long, flat and firm, with hard edges to catch your thighs; it's fine for moving around on when you're in go-for-it mode but after about an hour I had to stop to give my bum a rest.

What it does have are the two sturdiest grab-rails I've ever seen; if you ever carry a passenger on this bike (not recommended) they'll have plenty to grab. The rails are also useful for tying on luggage, well aft of the captain's position.

OK, so it's not a tourer; the Mastiff is strictly an inner-city hooligan tool with more than its fair share of rough edges, both cosmetically and mechanical. The harder you ride it, however, the better it goes and handles.

This bike positively begs you to get really naughty on the way to work - and it has the chassis to back up the free-revving Yamaha engine. The Mastiff's bite is definitely worse than it's bark.

The test bike, a 2004 model, is for sale at R50 000.

The 2005 Baghira Streetmoto, identical except for a single headlight and off-road front mudguard, will be available in South Africa soon at R54 000 for black or yellow and R55 000 for metallic silver.

- Test bike from Le Cap Motorcycles, Cape Town.

MZ Mastiff specifications

Related Topics: