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The simplest way to get a big discount on a new bike is to turn up at the nearest multi franchise dealer in the middle of December with a wad of used fifties in your underpants. Works every time. A few hours later I emerged with a brand new TDM850 Yamaha and over four grand poorer (one hell of a big pile of fifties). I had ridden a friend's and been immediately smitten by the huge production of low speed torque. It had more grunt than a 850 Commando, knocking out 58lbft at 6000rpm as well as 78 horses at 7500rpm.
My friend had impressed me by taking off rapidly in fourth gear with hardly any clutch slip! The brand new five speed gearbox was both loose and stiff at the same time; requiring a hefty boot that only rarely managed to put the bike in gear - it soon became obvious why he liked taking off in third or fourth, the gearchange action was so horrible that he had no choice. I consoled myself with the thought that the box would surely get better when a few miles were put on the clock.
The riding position was relaxed for town riding and we chuffed along happily enough the 50 miles to my humble abode in Walsall. The lack of protection afforded by the plastic was par for the course. I hated the twin headlamp binacle perched below what would otherwise pass for an attractive half fairing.....if only Yamaha had had the guts to dump the plastic altogether I am sure the bike would have looked all the better for it. My hands were frozen solid, useless clumps of leather and flesh, by the time I arrived home.
I have always liked big vertical twins, having been brought up on various Triumphs and Nortons but I soon tired of their lack of reliability. I also owned an XS650, a fantastically reliable machine but slow and awful handling. With a dry weight of 440lbs the TDM was lighter and endowed with a vastly superior chassis, as well as much more power and torque, so some progress has been made.
To my mind, 440lbs is excessive for a vertical twin, even a 850cc one. Yamaha make a 600cc four that weighs less than 400lbs so I would have thought that the TDM could lose a 100lbs if they put their mind to it - just chucking the plastic and the massive exhaust system ought to save 75% of that! On the road, though, the Yam does not feel like a 440lbs, it manages to combine the light feel that its trail bike look might suggest with an overall feeling of security that is well at odds with its long travel suspension.
A lot of this must be down to the rigidity of its steel Deltabox frame, the narrow, relatively low slung engine dispensing with the need for lower frame members. The cylinders are radically canted forward as per FZR fours, although the way the clutch and gearbox are tucked upwards make the engine look like the whole unit has just been twisted through the vertical. High technology freaks will be relieved to see that the motor is watercooled and that there are five valves per cylinder.
After 500 miles of mild running in, a period over which the vibes noticeably diminished, only a 4250 to 5000rpm range was left that was reminiscent of running a 650 Bonnie at around 6500rpm. A hundred miles of cruising at, say, 85mph, would thus lead to dead fingers and fading vision, although much to my relief it showed no sign of imitating its British brother by either depositing essential bits of chassis on the road or self destructing.
The engine features balancers, of course, but no one has yet explained to me how engine balancers work.....yes, you can get them to cancel out primary imbalances at one point in the combustion cycle but at other points they produced there own vibration. I think what happens in the case of the Yamaha is that reciprocating masses are minimal, crankshafts are dynamically balanced and what vibes are left are redirected from the vertical to the horizontal by the balancers where the frame and chassis can more easily damp them out.
It used to be an old and secret art, designing frames to soak up the worst of vertical twin vibes, but judging by the smoothness of the TDM at all over revs, one that Yamaha has cracked. Perhaps their experience with the old XS650 helped, that had such excessive mass that most of its vibes were soaked up (although it could never attain the levels of smoothness associated with the TDM)....perhaps if the TDM lost that 100lbs it would become as bad as the old Brits!
The most outstanding feature of the TDM, I have found in the last 6000 miles, has been its torque. A total idiot could ride one, it almost makes the idea of an automatic gearbox redundant, at most it just needs two gears! The gearbox has become easier to operate and slightly more precise but it is ridiculously easy to miss gears when changing down. The clutch is light enough to hold on all the time at traffic lights as an alternative to spending fruitless hours searching for neutral.
Acceleration in the lower gears is phenomenal. Just opening the throttle in first or second is sufficient to have the front wheel pawing the air; even hard acceleration out of corners in third causes the front end to go light, the bike driving across the tarmac as the front wheel patters over the road. It catapults up to 110mph faster than my brain can happily cope with, then slows somewhat up to an indicated 135mph. It will cruise tirelessly at the ton all day, the engine out of its rough spot and remarkably smooth for an 850cc vertical twin (better than a Commando).
The Dunlop tyres stick to the ground with tenacity and the suspension has shown no signs of wear so far. Adjustable preload and damping is available at both ends and I've managed to set mine up on the soft side of firm. It eats the potholes with ease yet doesn't allow any wallowing in either a straight line or through the bends. This paeon of praise was somewhat ruined by the seat, which was not as comfortable as it should have been and produced a sore bum after a 100 miles.
With a seat height of 32" it's passable for those short of leg and the reasonably placed footpegs allied with slightly higher bars than I would have liked were otherwise comfortable enough for 150 miles of fast road work and a blessed relief, in town, after the cramped arrangements of a race reptile I had been previously posing around on. The 850 will stay with 600 replicas on twisty roads, only losing out on fast A roads. The big difference is that the TDM is the kind of bike that adapts to how you want to ride rather than dictating the pace. Its excessive torque below three grand means it will meander along in BMW style; most relaxing and almost economical at 50mpg. The other side is using the throttle a bit, although not excessively, past 7500 revs power begins to tail off dramatically, although out of interest I have had the engine in the red in the lower gears. Used to the frantic gearbox action of across the frame fours it took me a while to adapt to just opening the throttle but that feeling of gut wrenching acceleration was wonderful. Not so wonderful was the 39mpg that resulted.
It made me wonder how I had ever given up my Commando for the dubious delights of a Honda four. That's where the TDM shines - it's taken all the attributes of the best of British vertical twins - excessive torque, narrowness, flickability - and added to them even more grunt, compliant suspension that is perfect for our ruined roads and rock steady handling. Compared to the old Brits its 50lbs too heavy and nearly 20mpg down on fuel (the TDM averaged 42mpg under my hands) but this is only the second version of the engine (the Super Tenere was the first) and it may get better in years to come. I can't wait to get my hands on an aftermarket exhaust which will certainly lose mass and may help economy.
The consumables have been pretty good, still plenty of life left in tyres, pads and chain. Engine servicing is easy enough for the DIY fanatic (my experience of dealers had been such that I feel it's better to put a match in the tank than hand over the machine for a service). 10 valves is excessive but the upside is that they have required no adjustment from new. I change the oil and filter every 2000 miles just to be on the safe side. Yamaha build really tough four strokes, these days, so I have no qualms on longevity. Even the finish has held up well through the winter with only a few spots of rust on the rear subframe and exhaust.....but with a new bike I'm pretty fanatical about cleaning and polishing.
There are a few on the used market now, but nothing much under £3500 - if Yamaha were selling them for around that new they could probably move a few hundred a week but at a retail of over five grand I can't see many people buying them. I certainly wouldn't have unless I could have got the big discount I did; now that I've bought it, though, I've got no intention of selling her.
P.B.
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You'd think that they'd put a good seat on a trial bike, wouldn't you? A nice sensible upright riding position, big fuel tank, some plastic for rider protection and that big vertical twin engine with bags of midrange......it should've added up to a brilliant long distance tourer but the whole experience was ruined by the way my 14 stone flattened out the seat, leaving me sitting on hard edged plastic. As much fun as being lacerated by a knife wielding skinhead.
The Super Tenere isn't really a trail bike. Its looks are so weird that I'm not sure what it really is! The acres of plastic makes it look bigger than it really is, with a dry mass of 430lbs, not bad for a watercooled, DOHC, ten valve vertical twin. Yamaha claim 70 horses at 7500rpm but either they're lying or the plastic has the aerodynamic efficiency of a brick shit house - the bike runs out of puff at the ton, topping out at 110mph.
It didn't really matter, the comfort level, seat aside, doesn't work much above 80mph, the riding position is just too upright for going any faster for any length of time. Besides, at 90mph the bike begins to wallow on its long travel suspension, doesn't like those long, fast motorway sweepers at all, meandering around in its lane like a drunk in search of somewhere to throw up a curry.
The Tenere's handling was a weird mixture. It seemed to go well in traffic, hard on the throttle and, in turn, the brakes, the wide bars allowing the bike to be whipped through the cars. But at a walking pace the Ten felt top heavy, would easily catch out those short of leg (I'm over six feet, found the riding position good), who'd find themselves suddenly falling off.
A little bit of care and attention in the early days pays off later in mastery of the machine. Practice makes perfect. Country road work's quite good, the tall seat letting me look over hedgerows to see what was coming - saved me from bumping into a tractor twice, these bovine farm hands drive like they own the countryside. The tyres squirm over bumpy corners but more or less held their line, the mono-cross back end being a touch more proficient than the forks, although in their praise the latter were fitted with gaiters and thus needed no attention.
Quite a lot of practice was needed to perfect the gearchange, about on a par with an old BMW boxer, Clunk, clunk, clunk every change. If that wasn't bad enough, there was enough slop in the transmission to make less than 2500 revs in the taller gears akin to taking a hammer to the engine, forcing me to use the gearbox when I would've much preferred to exalt in the low speed torque of the engine.
With 50mph on the clock there wasn't much point changing down from fifth, just wind on the throttle and enjoy the surge forwards as those big pistons hammered through their short strokes and the hi-tech cylinder head did its business. Staying away from the bottom and top of the rev range provided smooth running, two gear driven balancer shafts taking the bite out of the primary vibes. Unlike the old British twins, the reciprocating masses must've been pared right down using the latest in CAD techniques. For a big vertical twin the Tenere's smooth.
After about six months cursing the seat, I pulled it off, tore the cover off and cut up some high density foam. I glued it all back together, but it wasn't perfect, there was something wrong with its basic shape. With my bulk aboard there was about six inches left for the passenger, who usually ended up having their thighs reshaped by the grab-handles on the side or even half sitting on the neat rack. The bike was not popular with my women friends, which meant I usually ended riding into the distance on my own. Violin time!
Having a six gallon petrol tank to grip over bumpy going was quite useful, its massive bulk making me feel like I was part of the bike rather than merely perched atop it. I usually bettered 50mpg, although it was possible to go down to 40mpg. The only problem with the six gallon tank was that when full the top heaviness became a bit dangerous, the whole bike feeling rather queasy. I usually kept below the four gallon mark, which still gave a 200 mile range, more than enough for even the renovated seat.
One element of the Yam's riding position was that it was easy to stand up on the pegs to relieve the bum-ache, a throwback to its off-road illusions. I did actually try a few mild trails, but on road orientated Michelin tyres there wasn't an excess of grip. The back tyre would whip from side to side if the throttle wasn't caressed the same way you'd go at a sixteen year old virgin. I had muscle and long legs to fight the bike when it wanted to fall over, midgets would find themselves buried under the machine when it suddenly let loose. Don't even think about riding on mud or river beds, not unless you want to test the resilience of the plastic (quite good, as it happens) and the human body (wear body armour).
I hardly used the brakes off-road, relied on engine braking even though that was accompanied by lots of transmission wailing. The Ten had twin front discs and a singular rear. Unfortunately, the brakes never worked very well nor very predictably. The back became very jerky, which was traced to a warped disc (at 18000 miles) but as I rarely used it I decided just to ignore its existence (the MOT tester didn't notice). The front went through pads in about 4000 miles, an astonishing figure given the lack of high speed braking, maybe a deliberate design fault to compensate for the ease with which the long travel forks can be put down on their stops. Wet weather provided many moments of incredulity whilst I waited for them to work.
Remedial action was taken in the form of EBC pads, new fluid and Goodridge hose, but resulted in only a marginal improvement. I took off the disc covers, hoping to improve the cooling but that made absolutely no difference. I kept bleeding the system, which helped a little. In the end I just became used to the brakes and compensated for their failings.
The back disc eventually seized up, causing the wheel to hop all over the place. A month later the spokes began to break up and I had to go home courtesy of the AA. With a wrecked rear wheel and brake some radical action was needed - a visit to a breaker where a drum braked wheel was found that would take the rear axle. The brake was a bit indifferent but worked better than the disc.
That happened at 39000 miles. The engine must be commended because all I'd done since buying the 1991 model with 6500 miles on the clock was change the oil and filter every few thousand miles. A nasty bit of design was that it was a dry sump engine with a separate oil tank, a pathetic throwback to the forties. Sophisticated electronic ignition, auto-tensioner, a ten valve head that was still within service limits and twin carbs that stayed resolutely in balance, provided an impressive engine package.
The original chain had gone to 11000 miles but subsequent O-ring chains couldn't last for more than 8000 miles, even when I went to the trouble and expense of buying a new set of Yamaha sprockets. One chain only lasted for 5000 miles and chains couldn't be pushed beyond a certain limit of wear because the gearbox became full of false neutrals.
The gearbox became no worse over time. The same couldn't be said for the finish. Despite living in the house when not in use, and being cleaned lovingly every week, at times the bike seemed to be dissolving into corrosion before my eyes. The black '91 model helps some of bulk fade away but it really is an ugly bike without rhyme or reason, none of the lines (of engine, frame or plastic) matching. The rust and alloy rot just made it look all the sillier. By the time it was three years old I was forced to do a strip, respray and beadblast some of the alloy.
I've seen some real rat Tenere's with less than 20,000 miles, which perhaps explains why older ones can be had for silly money. With the toughness of the engine (early ones could crack the oil tank, drain the motor of lubricant resulting in a terminal seizure....), a near wrecked looking chassis shouldn't put you off if the price is right. It's such an ugly bike that it might even benefit if all the cycle parts were dumped and a bit of mixing and matching was indulged via the breakers.
From the seat, the Ten's a fun bike to ride, that big twin engine giving it loads of character. It's not a serious off-road hack, though it'll roll across the odd roundabout if necessary. The engine's tough and the chassis can be bodged with bits from breakers. There's a great bike trying to get out, and the used prices make it excellent value.
Keith Garrand