|
1997 Yamaha TDM850 In the orderly world of motorcycle manufacturing every bike fits into a neat little box describing its form and function - sports bike, tourer, commuter, trail bike and so on. In fact the newly relaunched MCN has decided to break its advertising section into just such a set of categories - presumably in the misguided belief that buyers these days aren't looking just for a GSX-R750; what they're actually after is a sports bike, and maybe they can't just look through ads in an alphabetical list, so "Sports Bikes" is better... Trouble is that Yamaha's TDM850 doesn't fit into the categories very well. When it was first launched six years ago, the whole style of the bike was unlike current machines - trail bike influenced, with high ground clearance and flat bars, yet definitely a road bike with a big twin engine, low exhausts and road tyres. It developed a bit of a reputation as a fun bike - easy to ride, easy to wheelie, do anything kind of machine. It's undergone a few revisions over the years which culminated in a cosmetic makeover last year and engine and chassis changes to sharpen things up a bit. Nevertheless the TDM remains a bit of an odd man out - no other manufacturer offers a bike quite like it, which means it holds a bit of a niche. Yamaha themselves categorise the bike as "New Sports" - which as we found out, is pretty much what it is, and nothing like the nutter supermotard-type bike everyone originally assumed it would be. Here's what we thought after a couple of weeks living with a TDM. Big bike
The first thing that strikes you about the TDM is how big it looks. The front end in particular is high, with the wide bars and fairing merging into the tank in a smooth set of curves. The redesign last year was definitely for the better - the TDM's style is really unique, and we reckon looks great. The twin headlamps look even more like eyes, the fairing is more organic-looking and although the red paint job this year isn't quite as good as last year's yellow, it's still a pretty looking bike. It's also a long bike, and actually a pretty heavy one too; though this is perhaps accentuated because the weight is carried quite high - lifting it off the stand and wheeling it about is harder work than you expect. From the saddle the fairing is a long way off, adding to the impression of size. Mind you, the seat isn't any higher than normal, and while real shorties may still have problems, the majority of riders will find the TDM no more difficult to hold up at traffic lights than any other bike. Real smoothie...
Firing up and clunking into first, the clutch feels smooth and precise (unlike many Yams) and the bike feels well balanced at low speed - it's one of those bikes you can bring to a halt and keep your feet up for what seems like ages before it finally drops on one or the other. The engine was a real beauty; very smooth, and with a linear power curve and nary a glitch in carburation right up to the redline, and beyond... Yamaha have chosen to lower the gearing in comparison with the TDM's sister bike, the TRX, and it's actually a bit under geared - even when loaded up would happily pull through readline in top (an indicated 130mph or so). The only thing to slow your progress is the gearbox; not as bad as some recent Hondas, but nevertheless not one of the best. Clunky and slow to change, it required a firm, steady foot to be applied. Don't bother to rush things, you'll just end up with crunching and false neutrals, once again adding to the "touring bike" image. Mind you, don't expect any thudding twin noises 'cos this one's been silenced out of sight - in fact it's impossible to hear the engine above the wind noise once you're above about 60mph. Part of this is actually due to the fairing, which positioned as far away as it is, means buffeting can be felt unless you lean foward into the area of still air over the tank. Bendy round the bends
Hit a bit of bendy road, and the TDM is pretty disappointing. While it doesn't handle badly, it's definitely not the fast-steering, point and shoot style of bike that the semi-trail-bike styling hints at. Instead you have to ride smoothly and plan ahead to get the best from the bike - treat it rough and tough and it'll either bite back or just go and sulk. This is mainly due to the suspension being pretty low-tech; forks are soft and with light damping, while at the rear the shock has a handle to easily change the spring preload for carrying a passenger but that's about it. Not much adjustment - we'd have liked a lot more, particularly as all round stiffening up would have improved high speed bend swinging considerably. As it was the weight of the bike is carried high, and with the suspension dive under braking the weight transfer was considerable, making the bike unstable and losing feel from the tyres at the critical turn-in point, often causing the bike to run wide just when you didn't want it to. Stopping wasn't a problem for the brakes, which although being low-tech in comparison with today's six-piston jobs were still able to haul the bike to a stop or lock the front wheel - but the weight transfer and diving forks meant it was difficult to use them to the utmost with confidence. Long limbed tourer
So what's the TDM good at? Well the smooth engine, don't- like-to-be-hurried gearbox, and gentle suspension all tend to point to the touring life, don't they? The riding position is certainly comfortable for all-day riding, and the seat is definitely a change from the sport bike saddles we're used to. In fact TDM's a very inviting bike as a transcontinental tourer, particularly for those riders who are more interested in seeing a little along the way; on a sunny day, cruising at a sedate 80mph or so on a broad A-road the high riding position gives you ample opportunity to take a look around and enjoy the scenery. The fairing is placed a little far away to offer the best protection, but then it's not a full dustbin job anyway. We got around 42mpg thrashing the nuts off it, so on a longer run with less throttle wringing a range of 150 miles to a tankful should be easily possible. Even the footrests have little extensions on them which allow you to place your feet in a variety of positions, a bit like foot boards but without the ground clearance problems. Summing up
The TDM is certainly one of a kind, but definitely not what we expected. Treat the bike as a stunt machine, try and wheelie, stoppie, throw it around bends and generally act like a nutter and you'll be disappointed - it's just a bit too heavy, a bit too long, and a bit too soft for all that. But forget the sporting tricks and think of it as a do-everything tourer, and you'll not be far off. The engine is the star of the piece - it's a refreshing change from a four, and generates some really smooth, effortless power. The brakes work, the handling's fine until you start to push it, and the riding position is good for the long haul. If you're looking for a general-purpose bike and want something a little different, try a TDM - but if you want to emulate Boris Chambon, get a dirt bike and put Akront rims and fat tyres on it - the TDM's just too nice for all that hooligan stuff! Yamaha TDM850
Engine:Liquid-cooled, 4-stroke, 10-valve, DOHC, Parallel-twin
Bore x Stroke:
Displacement:849cm3
Compression ratio:10.5:1
Carbs:Mikuni BDST 38 x 2
Max. Power:80.2HP(DIN)/7,500rpm
Max. Torque:80.4Nm/6,000rpm
Ignition:Transistor Digital
Starter:Electric
Transmission:5-speed
Final Drive:'O'-ring sealed chain
Dimensions (LxWxH):2,165 x 790 x 1,285mm
Wheelbase: 1,470mm
Seat Height:805mm
Wheels:Alloy 3 Spoke Tyres: Front - 110/80 ZR 18
Rear - 150/70 ZR 17
Suspension:
Front - 43mm forks adjustable for spring pre-load
Rear - Monocross with adjustable pre-load
Brakes:
Front - 2 x 298mm discs with four-piston calipers
Rear - 245mm disc with dual-piston caliper
Dry Weight:198kg
|
