Copyright (c) 2008 GoodMotorcycles.com
Young I wasn't but I still wanted a bike to buzz around on. I needed a mix of power, economy, light weight and reasonable handling. Most bikes which had more than 20 horses were either too heavy or too lacking in economy. I wandered around several dealers, turning down expensive HP offers and ignoring their laughter when I demanded good economy. The magazines were flicked through but nothing inspired. A friend of a friend's son had just passed his test (illegally!) on a derestricted TZR125. I didn't really want a stroker but it was offered for a weekend's test ride.
Most older readers have a prejudice against two-strokes. Visions of Norman Nippy's, Bantams and fragile early Japanese howlers filling their minds. It was immediately evident that the TZR was way ahead of those old horrors. Trilled into life the first mild kick of the lever, hardly any exhaust smoke. Derestricted to 22 horses, the 124cc stroker single was able to rumble along at low revs without any problems. Went a bit more urgent at 5000 revs but didn't really pile on the power until past seven grand when the tacho swung vividly around to 11000 revs!
The engine was fitted with electronic ignition and the famous power valve (YPVS) system. Along with clever porting, made the motor both pleasant at low revs and quite fierce at the higher end of the range. I don't weigh all that much and the TZR hit the scales at less than 250lbs. This power to weight ratio gave the bike a harder edge than my last bike, a GSX250 Suzuki four stroke twin. Both died a death, as if slamming into a brick wall, at 90mph. More than fast enough for me. Over the weekend, the fuel worked out at 68mpg (compared to 45mpg from the rather worn Suzuki), which was just about acceptable.
The TZR looks quite racy but has a sensible riding position and half decent saddle. Fine, if like me you're on the small side, but its compact nature probably wouldn't suit those with bigger frames. Taking the wifey on the back revealed that excessive mass had an immediate effect on performance and ruined the marginal suspension. But she wasn't keen on pillion work and was looking for an excuse to avoid the motorcycle experience.
The clock read 14,200 miles. The price was £775. There wasn't anything else remotely interesting in that price range, so I ignored my reservations and did the deed. Wearing an open-faced helmet, goggles and an old Barbour jacket, I received a few odd glances as they were in strong contrast to the flash Yamaha. I always had a laugh at the poseurs who wandered around Southampton town centre in full leathers, all oddly baggy in the wrong places once the riders were standing upright.
All went well until the first time it rained. I found the narrow, 17 inch front tyre liked to wander a bit (in the dry). Nothing a tight grip on the low, narrow bars wouldn't keep under control. The switches, by the way, were a touch too small for my fingers encased in proper leather gloves - none of this Gortex rubbish, just thick hide. But when the rain splattered down on the tarmac I found that the front tyre was all too ready to skate over the road. In my humble opinion, a good case can be made for slow reacting 19 inch front wheels on bikes that are light in mass and low in power. Tyres also last longer (9000-10,000 miles in the TZR's case).
The TZR could certainly do with a modified front end or maybe some better rubber than the cheapo Japlops. I had to ride really gently in the wet, try to avoid using the front disc and generally live more in fear than happiness. Time and experience did help a little, after six months it no longer seemed such a great problem as during those first few weeks. Perhaps I'm just a BOF! You wouldn't have guessed that, though, from the fast progress I made through the traffic.
Even more fun was had on country roads where the bike could be ridden flat out. If the front end was a tad imprecise, the lack of mass meant it could be chucked from side to side with hardly any muscle input. On the power, the exhaust wailed, whilst the immensely strong Deltabox frame kept the bike from getting seriously out of hand. The only limit on the extent to which it could be hurled over was the tyres' grip - I only used another replacement set of the same brand because they were available very cheaply.
On the motorway I had to ride the little stroker flat out to avoid looking like an accident waiting to happen. Full of visions of being mowed down by impatient car drivers or becoming the cause of a pile-up. Even ridden like that it bettered 50mpg against a normal average of close to 70mpg - the derestricted TZR's are more economical than their restricted cousins! With a 12 litre tank I could get over 175 miles before having to search for a petrol station. By then the seat was becoming more than a little uncomfortable, though I have done over 400 miles in a day without setting the piles off! Overall, it was pretty easy to become one with the machine and adapt to the way it loved to sing along at ten thousand revs. In fact, large and sensible four strokes of modest power became rather boring to ride.
In 18 months the Yamaha managed to clock up 27000 miles before it started to smoke and rattle. Shot piston rings and bore, but replacements were readily available and easy to fit. I cleaned up the powervalve and fitted a new but heavily discounted exhaust as the old one's matt black finish turned crappy. The engine had a new lease of life and I was a happy man again.
There you go, then. It might not look it, but the TZR's a rather sensible motorcycle for those on a strict budget but who are not yet ready to be consigned to the C90 hordes. I'm tempted to fit a front end off an old British twin to sort out its handling, apart from that it's a bit of alright. Fills my day with lots of fun and makes sure I don't become old before my time.
Alfred Dunning
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When I first saw the Yamaha SDR200 I thought it was a homemade job, something about the thinness of the chrome plated frame tubing convinced me it was a well done back yard special. If the dealer had told me someone had taken a DT200R motor and thrown it into a Ducati-esque chassis then I would have believed him. The reality was that it was a Jap market model from 1987, taking the well worn idiom of a naked TZR125 and making a more road orientated bike out of it.
Power was a modest 34 horses at 9000 revs from the watercooled single cylinder motor. I say modest because I know someone who got more power out of a tuned TZR125, though the peaky result wasn't something any sane manufacturer would dare emulate. The ugliness of the exhaust system vied with the shape of the tail unit for sick bucket status but the rest of the bike was well shapely.
9000 miles on the clock, faded cycle parts and alloy rot ruined engine cases and wheels were just about in line with the £875 ticket price. The dealer must've recognized the lust filled grin as I caressed the bike, no chance of a discount for cash. He reckoned he made even more money on the hire purchase in commission than he made in pure profit on the ticket price. Weird world.
This is a small motorcycle. Anyone over about 5'6'' tall will find themselves all crunched up and most uncomfortable. I was just about able to contort myself into the little stroker gem, being almost as wide as I am tall! The shape of the back of the tank was ideal for resting my extra large belly upon but the seat was the minimal, sharp edged kind of nonsense that soon had me screaming my head off. It was just as well that my marriage prospects were nonexistent, the poor old tackle ended all shrivelled up.
As well as being small the SDR's also very light, as in 230lbs! This makes it illegal in the new licence category because of silly power to weight restrictions, but if you already have a full licence it means their prices are reasonable. The lack of mass is translated into an amazing amount of nervousness, just the slightest amount of pressure on the bars had it skipping all over shop. It felt like some tiny wheeled scooter rather than a proper motorcycle but it did actually run 17 inch wheels, albeit rather thin ones that were shod with ancient, hard Jap tyres!
The tubular frame was undoubtedly strong, the suspension unexpectedly stiff. A combination that resulted in the bike leaping from bump to bump, pot-hole to pot-hole, like some frenzied hare. Once I'd adapted to the minimal amount of force needed on the bars, it did prove precise despite the rigidity of the suspension that really needed a six inch pot-hole to make it move. I doubt if it was standard fare, lightweight Japanese bikes notorious for their soft suspension because Japanese men rarely weigh over 60kg.
The engine ran best at the top end of the power band though it could burble along nicely enough at lower revs. I never had any problems with plug oiling - Yamaha have been churning out small strokers for decades, have sussed the lubrication system. It was just a matter of not getting anywhere very fast unless the throttle was used to the full. Fortunately, the clutch and gearbox were an absolute delight to use, couldn't fault them. Made all the difference, encouraged me to scream around at maximum revs.
Whilst 34 horses ain't very much, allied to an ultra light and precise chassis they can make for very rapid progress up to about 85mph. The most I saw was 105mph on the clock but beyond 90mph the chassis felt like it was going to flop right off the road. Entirely down to the teflon tyres that didn't wear at all and therefore weren't replaced! In retrospect, I should've demanded new rubber as part of the deal but enthusiasm blinded me to everything!
The bike was top dog in town. Rapid acceleration allied with minimal mass and exquisite narrowness made for record times through the heavy London traffic. Single discs at each end could lock the wheels under a minimal amount of pressure. Back wheel slides were a particular delight because some component of the geometry or weight distribution meant perfect control despite the state of the rubber (or perhaps because of it?).
All this action took my mind off the groin and backside pains. It also turned in 30-35mpg, which meant an eagle eye had to be kept on the fuel level as less than 60 miles could leave the motor dying a death. This wasn't a problem on a long run because I needed to leap off and get the blood back into various body parts after less than 30 miles - it was that uncomfortable! The odd tingle from the motor also reached the bars and pegs but compared to the hellish nature of the saddle it wasn't really worthy of note.
The 195cc stroker ran without a hitch for the first 5500 miles. Just add oil to the tank, do the gearbox oil once and kick the tyres. With a single carb, electronic ignition and no valves (except for the exhaust's powervalve, of course) there was very little to do, as with most modern strokers. Then the exhaust haze went heavy and the engine was running very hot, reluctant to start. What the f..k was going down? The oil ring was worn out. A DT200R item was persuaded on and worked okay. The motors aren't identical, the trailster making less power at more moderate revs, but many parts can be swapped over - given the cheapness of SDR's on the grey import circuit, the easy availability of DT200R engine spares makes them a good deal.
I hadn't done much to the finish, as we hustled through autumn it began to go off to a remarkable degree. Only the chrome plated frame managed to escape the dreaded corrosion. I went into a frenzy with the cleaning cloth and polish, got it nicely shined up. Only thing was, the bike was left outside overnight and all it took was a bit of rain to turn it into an old rat again. Too much effort.
Amazingly, the calipers refused to seize up despite riding through the winter months. Pad life was excellent as they were probably still original yet refused to go down to the metal despite the clock showing 19000 miles. Fuel was heavy, oil wasn't; total running costs were reasonable, especially when compared to the Jap fours which go through tyres, chains and pads every 5000 miles, or so.
Despite my own excessive weight, I never really found the bike lacking in performance and handling was fun once I'd become used to its flighty ways. Come the Spring I did a final clean up - it wasn't too bad under all the crud - went back to the dealer I'd bought it off and traded in for a CB-1. Got £900 off its price! I heard later that the motor had blown its main bearings and seized up at 23000 miles. For once, I had good timing!
Mike Jennings
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The Yam RD125LC is still one of the most popular lightweight bikes, so my further experiences with the LC previously reviewed in the UMG may be of interest. As the LC's speedo approached 30,000 miles I felt some foreboding of imminent expensive mechanical or electrical disaster.
The bike has now reached 35000 miles and I will relate its recent history. My LC is a 21hp model, which with an Allspeed and bigger main jet can reach 90mph. Petrol consumption is only around 60mpg and as the Allspeed rusts through after only three years I am tempted to revert back to stock and enjoy improved consumption of 70mpg. I have owned the bike for over seven years from new and have full service records so can give reasonably accurate wear rates for tyres, etc.
I use the bike's performance whenever road conditions allow but never over rev it. Rear tyre life has averaged 4500 miles and front 11,500 miles. Chains last about 9000 miles and sprockets 11,500. Heavy wear reflects performance which is better than some 250s. Chain and sprocket sets are relatively inexpensive. Front brake pads have been replaced once in 35000 miles but the rear brake shoes three times.
Electrical replacements in the machine's life to date have been the indicator switch at £17, flasher black box £12, temperature gauge sensor £17 and battery which lasted seven years. The bike passed 30,000 miles and continued to perform well, however at 33000 miles slight traces of clutch slip were noticed if the bike was accelerated hard. After another 1000 miles the plates and springs were replaced for the first time (£18). At 34500 miles increased oil consumption was noticed together with some piston noise, indicating a worn bore. Up to this time the cylinder head had never been removed...
I am very attached to the LC after owning it for so many years. It seems to have more character than most Jap bikes and has certainly been the most reliable bike I have owned in 30 years of motorcycling. I decided to restore the bike to as new condition.
The restoration turned out fairly expensive, mainly due to cosmetic damage caused by a series of prangs in '87, which in retrospect were caused by my trying to go faster than my reactions could cope with. Anyway, the road is hard, so this series of prangs without personal damage had the desired effect and I slowed down and stayed on. The headlamp fairing, panels and tail were repaired and repainted by Dream Machine, who did a good job.
The engine was overhauled by my local Yamaha dealer who sold me the bike originally and has maintained an interest in it. The bottom end was found to be perfect, the bore was worn and bored to accept the first oversize piston. A new piston with rings cost £27, a new gudgeon pin £4, the small end £6 (it looked perfect but was replaced as a precaution). New gaskets were fitted throughout. I think the engine has worn really well, considering its small capacity and high performance.
I next turned my attention to the cycle parts. The handling had deteriorated as I found when challenged by a DT125LC rider on a twisty road. I saw him off but nearly frightened myself to death in the process. I realised the rear shock was worn and replaced it with a new Yam shock for £60. Roadholding is now good, but not as good as my TZR125.
The front disc's piston had partially seized for the second time, it was rectified and Goodridge hose fitted, the brake becoming superb. The rear brake seized due to all the salt on the road in winter. The six speed gearbox is still perfect and superior to that of the TZR!
The LC looks almost as good as new. The motor, which I'm now running in carefully, is as smooth and quiet as ever. I look forward to many more happy years with this machine.
Vince G Dusang
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I could not believe my luck - my cousin had got his girlfriend in the club and was being forced into a hasty marriage, the only way he could raise the necessary dosh for the mortgage deposit was so sell his beloved, 1988 Yamaha TZR125; prime meat with only 5000 miles of abuse on its clocks. It was even the derestricted, 21hp model. I had the cash and a deal was struck within minutes.
I am an old hand at this motorcycling lark, even if I say so myself, so you can imagine my surprise when I discovered I had bought myself a real fun machine. 21 horses is not all that much but when the bike only weighs 231 pounds dry and sports a Deltabox frame, the motorcycle is able to make the maximum use of what power is available.
I soon found that the Yamaha is the supreme town machine, once my ancient body had adapted to the sporty riding position there was no holding me back. Flicking up and down the delightfully fluid six speed gearbox, keeping the revs in the critical 7000 to 10,000rpm band and riding on the brakes (a single disc of ferocious power and good rear drum) I was soon doing all kinds of mad things in town at speeds more befitting a juvenile delinquent.
If its minimal mass aided flickability, acceleration and braking, it did make for a tiring ride over bumpy and neglected roads. A firm grip was needed on the bars and a certain disdain for the way it was thrown about. Suspension was able to cope with minor irregularities and even high speed bumps in out of town roads, but the kind of pot-holed neglect effected by our local town council went straight into arms and backside in a most disconcerting manner.
Fortunately, the Yamaha remained supremely controllable and I always managed to sneak the ever so narrow single cylinder stroker through the narrowest of gaps that even a C90 commuter would have second thoughts about. There was a kind of exultation in burning off a row of cars, careering past them in the right gear at about twice the advisable speed, assured that if things went seriously wrong and some bored out of his head dork decided to do a sudden U- turn, the Yam could be braked and flicked simultaneously out of harm's way.
Not that the TZR would let you ride in any other way. Sustained slow speed work the machine did not like, oiling its spark plug and running as if it held a grudge against the world. On one occasional, in the wet, when slowed by two lorries blocking most of the road, the plug oiled up just as I was trying to overtake. Death seemed imminent as the vehicles converged rapidly on the space I wanted to shoot through, until suddenly the plug cleared, the front end reared and the machine shot forward like some mad Pitbull about to devour a child. The handling on one wheel was decidedly skittish and only the willingness of a car driver to mount the pavement stopped metal hitting metal. Things become much worse if you forget to replace the spark plug every 5000 miles!
With a weird combination of 16" rear wheel and 18" front, shod with Roadrunner and Jap crap respectively, wet weather riding was always interesting. The tendency of the front wheel to slide away from under you and the rear to step out an inch or two made damn sure the throttle was treated with care and some degree of planning ahead was necessary. 230lbs may well be too little for reassured wet weather riding.
The Roadrunner lasted for an inordinate length of time - over 20,000 miles, although the front only lasted for 15k, perhaps down to the frantic way I employed the front disc. Eventual fitment of a set of Michelins firmed up the handling and gave massive reassurance in the wet.
The bike was generally stable on the open road and just about the quickest thing I've come across to get through a series of hairpin bends. It was so much fun that on many occasions I turned around and did my favourite bits of road again and again. Top speed was normally 90mph but the elusive ton on the clock was achieved a few times - quite literally down a steep hill, with a strong wind behind. Quite fierce vibes buzzed up from the motor as it was thrashed into the red through the gears.
This showed up a surprising quirk in the TZR design, it seemed to become more economical the faster you went - imagine your defence in court, that you were trying to save the environment by running your engine at its most efficient speed! In town it rarely did better than 65mpg, but on the open highways it was no problem to achieve 70mpg. This is better than the 12hp restricted model which a friend's son owned and does 50-55mpg!
If the machine's reasonable on fuel it's main running costs come from chain and sprockets which last little more than 8000 miles and front disc pads which are even worse at 6k, although I work the single disc so hard that it glows red hot in the dark! Pattern chain and sprocket sets are only twenty notes, so their early demise is not as bad as it could be. Also the rear shoes are still original and unlike the front, which required a 10,000 mile strip to avoid seizure, needed no attention.
With 29000 miles on the clock I was rather alarmed to find the front forks juddering badly under braking. This was traced to a cracked disc! I spent many a sleepless night fitfully imagining what would have happened if it had failed at a critical moment.....the replacement from a nearly new bike in a breaker only cost £15 and is given a daily look over.
Another expense is the battery which rarely lasts for much more than 15k, evidence of its poor state being constantly blowing front bulbs. With 41k on the clock the rest of electrics have behaved themselves, no ignition or charging problems. Even the switches are original and still work as nicely as ever.
Maintenance is a doddle. There's hardly anything to do. Checking the oil pump setting occasionally and changing the gearbox oil every 10,000 miles, the rest takes care of itself. Ridden hard the bike uses about a litre every 500 miles, less fervent craziness improves that to about 750 miles to a litre. That compares well with changing three or four litres every 1000 miles, and is a lot less hassle than on a four stroke.
Using good quality oil in the engine means that the normal stroker blue haze is pretty minimal, only in evidence on starting up or under very hard acceleration. The watercooled engine has been extremely reliable since I've owned the machine, it seems to thrive on being thrashed, preferring it to pottering about in commuter mode. I can see absolutely no need to let such a machine near a dealer for servicing.
It's still on the original exhaust, thanks to the oil coating from the two stroke process, although externally the black finish has turned rusty. There are quite a few aftermarket systems available that claim to boost power but I have to admit I'm not that enamoured by the stock wail and don't want my head subjected to the noise of Allspeeds and the like. Tank paint is still good but there are specks of rust breaking out all over the chassis, especially on the screws.
The Monocross rear end is still stock and shows no sign of wear despite the fact that I have not stripped down the shafts. The shock became a good imitator of a pogo stick after 30,000 miles but as the bike itself has always done a good pogo hop over bumps I haven't bothered to replace it. The front fork seals went at 15k when I was imprudent enough to slop in some thicker oil and went again at 25 and 33k even when I used the proper grade. The pitted forks doubtless don't aid longevity.
Even at its current mileage, the engine comes to life first kick, I can detect no diminishment in acceleration, top speed nor economy and it gives every impression of wanting to run and run. That's in contrast to the machine of my friend's son which was dead after only 15000 miles (despite being in 12hp form) - the motor seized solid and almost spat the youth off the seat. The dealer diagnosed a seized motor due to a lack of oil.....he had forgotten to fill up the tank! I bought the machine off him for a few hundred quid, so it seems I'm set up with enough spares for the next few years.
Gerald Parker
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After much thought I decided that the best way to start motorcycling was to buy a newish 12hp 125, pass my test and then derestrict it. I'm 42 years old, wanted to commute mostly in town but didn't want to look like a total jerk on some gruesome commuter. Also, I fancied some weekend runs. The last thing I wanted was to end up with one of the race replica style 125s, too much pain for my poor old bones.
Thus when a six month old Yam TDR125 was on offer at the local dealers I was rather taken with it. Looked a lot flasher than most learner machines yet had a sensible riding position and lots of protection from the fairing. When the dealer told me he would derestrict the engine for free once I'd passed my test I was sold on the bike. The clock only read 3750 miles yet I was rewarded with 25% off the list price.
The dealer frowned somewhat when I refused to buy any gear off him.....a mate had donated a helmet and an old leather jacket. Some ordinary gloves and boots would have to suffice. Starting biking in October is not the best move but there wasn't much rain just lots of cold fingers and feet.
The first few days were a bit traumatic. I'd done the basic training course some months before and kept forgetting what all the levers were for. Deciding that it would have to justify its purchase cost by being thrown into the maelstrom of crazed, careering cars, didn't help with the learning process.
Initially, I'd been quite frightened by the way the Yamaha would tear off from the lights in first or second, but once used to the pulse of acceleration it soon became apparent that after 50mph twelve horses didn't add up to very much. It ran nicely enough at low revs but really needed 3500rpm before it went into killer mode.......which lasted only to about 6500 revs when the power faded away to nothing.
It was hard work to put 70mph on the clock, something, that after a week, I felt quite willing to do. The engine always gave a feeling of fighting against itself, the watercooled stroker motor being good for about 30 horses in more civilized countries.
In reality, the lack of power and speed stopped me doing really stupid things, which despite my great age, the new found freedom of motorcycling suddenly seemed to make necessary. God knows how some 17 year old youth survives.
Keeping me on the straight and narrow was the chassis. The centre-piece was the steel Deltabox frame which together with the long travel suspension never gave me a moment's worry. I felt really sorry for the old codgers on frail commuters whose proper place was wobbling along in the gutter. I soon learnt to keep an eye open for pot-holes. The suspension would absorb the worst of the shock from foot deep craters, but the 235lbs of motorcycle could be thrown about as the front wheel twitched.
It certainly felt a lot safer than the CG125 I used in the training school. The Japanese tyres defied their origin by sticking like glue to the tarmac, even when the inevitable rains began to fall. They even felt okay over iced up roads, although I had both feet down just in case - with a 34 inch seat height I was thankful for being over six feet tall.
The bars seemed inappropriately wide, to my taste, the bike not needing much effort to twist and weave through traffic. I would have preferred narrower bars and wider plastic so that my hands were kept out of the cruel wintry winds. I had soon bought some proper leather gauntlets, but even with these my fingers went ice-cold after only five miles of town work. The odd blast of hot air from the radiator kept my lower body a little warmer but come a heavy storm, despite the acres of plastic, water got just about everywhere. The old leather jacket turned into a big sponge. By the end of the winter I was togged out in proper wet weather gear and a lot better for it. Anyone coming to biking for the first time should factor in the expense of clothing.
Much to my chagrin a friend had bought a Vespa scooter, which had lots more rider protection and kept up with the Yamaha. True, on any serious bend he was left miles behind, a wallowing mess as his tiny wheels bounced from bump to bump. But he'd bought his pristine machine for less than a grand. Worth thinking about if you have no street credibility.
I was a little disappointed with the Yamaha on the open road. It was struggling to maintain 65mph and didn't like to do more than 70mph. The tacho just didn't want to go much beyond 7000rpm, I could almost feel the engine gagging on its restricted powervalve. Fuel wasn't very impressive, either, varying between 50 and 70mpg, depending on road conditions rather than outright speed. It was least economical running up hills or into a headwind.
The dealer reckoned all the maintenance it needed was to watch the oil level in the tank and to change the gearbox oil every 5000 miles. Ignition was electronic and there were obviously no valves, camchains or multitude of carbs to worry about. In four months I did over 3500 miles without doing anything to the engine other than adding oil to the tank. The drive chain showed a disturbing need for adjustment after 5000 miles were on the clock and both tyres are wearing out fast. Not impressive for such a mild, light motorcycle.....I would've expected much better life than what I used to get from my Metro....but then what do I know?
Finish, despite hardcore commuting through the winter, has survived well, except for the matt black exhaust near the front of the engine. I tried some heat resistant paint but this fell off as soon as the motor warmed up. The exhaust is fitted with a catalytic converter, so will cost a fortune to replace.
Engine noise was minimal, mostly a burble that would try to turn into a hard wail when the throttle was used in anger but was never entirely successful. I talked with some spotty youth who had both derestricted the engine and degutted the silencer, who reckoned that his modified bike was good for 110mph. I rather doubted this tall story until my mind was completely closed down by the terrible din thrown off by his exhaust as he wheelied up the road. I'm all for having fun on two wheels but I felt like smacking him in the face, so God knows what the cagers thought.
I recently had a go on an acquaintance's old CB125 single. What a rolling wreck! The gearbox was a terrible mess that made it almost impossible to ride and the vibes felt like the engine was trying to thrum its way out of the frame. I hadn't realised how civilized was the Yamaha. The six speed gearbox, and light yet sensitive clutch, meant I was able to adapt quickly to the gearchanging chores. If I'd started on an old Honda single I'd probably have ridden it right through a car whilst I was trying to make the gears work. I would rate the Yam high as a machine to learn upon.
It doesn't seem in any way to be the kind of mount that some 17 year old in school or out of work could ever hope to afford, especially with the silly insurance rates. It's too expensive to buy or run for the usual commuter, so that just leaves relatively rich middle-aged nutters like myself who have suddenly decided that motorcycling is the way to go.
Can't say I've been disappointed. A week prior to penning this I passed my test first time - I'm sure my sensible appearance helped, as did my off hand explanation that I was borrowing my son's bike for the test and not really some kind of Jekyll and Hyde lunatic. He actually told me I was riding a bit too slowly, but let me off.
The dealer, true to his word, worked magic on the powervalve. At first I was a bit annoyed, it seemed just the same at low revs. It wasn't until the new found power kicked in at 7000rpm that the transformed nature of the TDR was revealed. The first highway dash put 85mph on the clock without trying. A bit of persistence broke the 100mph barrier.
I backed off quickly, my mind suddenly full of worries about the tyres exploding or the engine seizing up. With so little mass, the 30 horses provide some wild acceleration that gets the front wheel up in the air and makes cars look like they are going backwards. Handling and braking still seem more than adequate whilst petrol is no worse at 60mpg. I can see how people get immersed in the power crazed game of uprating to something bigger every six months but I'm sticking with the Yamaha for now...
G. Jones
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There are some bikes that get into the mind so deeply that they are hard to shake off. In 1985 I learnt to ride on a brand new Yamaha RD125LC. A fantastic year's riding followed with only the consumables replaced. Test passed, there followed a couple of years on RD350s which were even more fun but a bit finicky and unreliable. Then came a job with a car and no bike until 1992 when the job disappeared and I suddenly needed some kicks.
Enter a 1986 RD125LC with 30,000 miles on the clock. This one was derestricted, the watercooled single cylinder motor putting out about 20 horses. It wailed and screamed, shot off up the road, which resulted in a big smile which I couldn't hide from the vendor. My face was all lit up judging by the way he refused to budge on his price. Well, it was a one owner in good cosmetic condition and I'd had a big pay off from my employer.
These bikes are neat bits of engineering, Yamaha at their best. With watercooling and a reed valve, the motor wasn't exactly simple but very robust for a stroker and pretty easy to control even in derestricted form. By modern standards the styling might've looked a little dated but I think it has a quiet charm all of its own that in ten years time will still be attractive.
I seem to recall that my bike didn't weave at 70mph like the one I'd just bought. I put it down to the passage of time, rose-tinted memories and all that. At least until the weekend when I poked around the chassis. There was some movement in the rear wheel. I thought the bearings were shot but the wheel spacer had been replaced with ill-chosen washers. A visit to the breaker and the large sum of 50 pence procured a proper spacer.
The RD might have an old fashioned tubular frame but it's a good one with plenty of rigidity to withstand its 220lbs and 20 horses. With the back wheel sorted its stability more than matched my memories even with as much as 85mph on the clock. Because it weighed so little bumpy roads would give me a pounding and let the chassis bounce around on its springs. It always felt controllable and never seemed to come close to a speed wobble.
There was a sharp outpouring of power from 6000 revs onwards. The kick seemed out of all proportion to the machine's cubic capacity and power output. Part of it must've been down to the directness of the two stroke power cycle, part down to the low mass and the final part down to the way Yamaha had matched the reed valve with the exhaust system. The 12hp version tended to die a death at 7000 revs, which whilst an ideal restraint on learners would've been boring for the more mature motorcyclist.
Derestricting the motor removed some of the friendliness at low revs, although the engine still ran it sort of burbled rather than crackled. Even in 12hp form it had quite an appetite for spark plugs that was even worse in my bike. Every 800 miles I had to put a new one in, to avoid a motor that spluttered and coughed when in town. When the thing suddenly caught with the throttle wrapped open, the front wheel would rear up as the power screamed in, and I'd have to throw myself forward with a back wrenching viciousness.
It was a lot easier to change the plug before it gave any trouble. Modern oils meant that there was little of the coking up of old, with only the mildest cloud of burnt oil out of the exhaust. With electronic ignition there was nothing to do to the engine other than check the oil tank level and change the gearbox oil (every 2500 miles).
Deciding that I'd keep the bike for a while it seemed like a good idea to rip the rear swinging arm and mono-track suspension out to grease the spindles. A wet and wintry autumn was threatened by the weather forecasters. Everything came apart easily, the as new bearings were well greased. Because of the lack of protection from the rear mudguard, the area is attacked by all kinds of gunge. The spindles can be quick wear but they last okay if given a six monthly strip down and grease. It makes all the difference.
The past owner had obviously gone to some lengths to make the RD long lasting. The chain was an O-ring job that hardly ever needed any attention (plain chains wear out in about 5000 miles). The electrics were mounted on extra rubber and smeared with Vaseline (flat out, the engine gets a little tingly which can affect the stock electrics). The forks had gaiters and the calipers had been rebuilt. The alloy on the wheels and forks never corroded because they had been coated with some clear varnish.
Before the winter set in for good I thought it'd be neat to do a week's touring to really test the limits of the RD. They do lose a lot of their go with a pillion on the back. The mass also crushes the rear shock and makes the bike bounce all over the place. I limited myself to a small tent, a few clothes and a sleeping bag. I want to enjoy myself not get into a fighting match with a grossly overloaded bike.
All went well as I headed for the Scottish lowlands, some 150 miles from my home. I was able to hold 80mph on the motorway, the tiny handlebar fairing doing a surprising job of keeping off the wind and the motor wailing nicely. Then the rain started falling and didn't stop for the next four days. I ended up in a Glasgow hotel dodging around the town in between rain bursts, having dumped the RD in the hotel's garage. Glasgow is a weird place with areas of massive depredation, which had me legging it pronto and lots of old, interesting buildings in the centre. I never fully understood the Scottish sense of humour and was happy to head for home.
It was still pissing down, I was soaked through within minutes but persisted, riding the Yamaha on the edge of its Metzeler tyres. On the motorway there was no choice but to hustle along at 80mph, the cars would've thrown me off the road if I went any slower. The rain became really frenzied, visibility poor and my brain responding to my frozen extremities with pain messages on a par with an exposed nerve from a rotted tooth.
About a 100 miles from home there was a horrible, grinding noise running through the engine, screams of tearing metal not so much heard as felt through the chassis. I hit the clutch just after the back wheel seized solid. The momentary skid was vicious enough to have the back wheel all over the place. If I'd been a moment slower I would have been thrown down the road, torn asunder from an 80mph assault on the concrete surface.
As it was, we had hobbled to the hard shoulder where I sat on the bike, water dribbling out of my clothes, soaked so far through that my underwear squelched whenever I moved. Like a beacon in the middle of a sea of swirling madness the rescue service's telephone stood ten yards away. I dragged my body, carrying about a ton of excess water, to it and got the AA to come to my rescue. Before they turned up I'd managed to change into some dry clothes by draping the tent over the telephone, so narrowly missed out on the joys of dying from pneumonia.
It took me a good month to become interested in the RD again. The engine had obviously seized (with 39000 miles on the clock) and was going to cost lots of dosh to repair. What had happened was that a big bit of the reed valve had found its way into the engine, leaving the bore scarred and the piston broken. The crankshaft felt like it was due for some new bearings so I started hunting down a secondhand mill.
Several breakers were visited before a suitable motor was found, out of a crashed bike that still sported its L-plates, so I was pretty sure that it was in 12hp form and not unduly thrashed. Putting this engine in my frame was painless but I bought a new reed valve just to be on the safe side. I soon had the motor set up in full power tune and a few spins on ice covered winter roads revealed that it was, indeed, a good ‘un.
The year was started off in good form by showing a mate on an CB250RS who was boss. The Yam was more than a match for most four stroke 250s, being almost half the mass and not having that much less power. It was a real ego boost to burn off these bigger bikes and at around 60mpg fuel was just as good, if not better.
The sight of a well put together RD350LC stopped me dead in my tracks. More nostalgia and dubious memories. The owner turned up and only wanted £500 for a quick sale. It was in such nice condition that I could not resist despite the bad recollections about its lack of mechanical reliability.
I kept the 125 for a while, but it seemed to lack the verve of the bigger bike in direct comparison. The only thing I really missed was the economy, as the RD did no better than 35mpg and tore through the consumables at a rate that must've made tyre, pad and chain manufacturers extremely rich. But the kicks seemed to make that worthwhile. The 125 went to a good home, some forty year old who wanted to get into biking. I gave him a blast on the back of the 350 to show him what he had to look forward to.
J.K.
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I will start well into my biking
career with an RD125LC. A Mk.1 full power model of 1983, costing
a mere 175 quid- cheap at the time as it appeared to be in very
good condition. Already fitted with a K&N filter, jetted carb
and a very, very loud Micron pipe, ear-plugs were essential! Two
weeks was all it took for the local plod to give me a choice -
keep the illegal pipes and take the consequences (probably life
imprisonment) or fit something quieter. I chose a legal Micron.
I still recall my fist blast down the road After a selection of
small four strokes, the same handful of revs and dropped clutch
saw me off up the road like a smart suited git to a Volvo auction
- scared myself shitless. From then on I was hooked on strokers.
There's nothing quite like the frenzied howling of a good stroker.
Over the next two years I amazed myself. I generally keep a bike
about six months before boredom or self-destruction sets in. Somehow
the RD was different, never boring and a massive grin factor on
each and every ride. However, it was not long before problems
began to emerge. The dreaded sound of piston slap began to filter
through the induction and exhaust roar. Not the kind of thing
to ignore, not unless you wanted the joys of a stroker motor seizing
up at high speeds.
Without undue haste, I quickly beat it into submission with a
rebore, piston and rings. The rebore was done by a mate down the
road for a tenner and the piston and rings purchased from the
local Yamaha dealer. About a week after the rebuild, screaming
across town, the bike started to slow down. No matter how much
I twisted the throttle no more power was available. Down through
the box, full throttle, again to no avail. Heat rose off the engine
as if it was going nuclear.
I stopped in a lay-by to let the engine cool down. Resulting in
25mph in top gear at full throttle. I was overtaken by an old
codger on a step-thru! At least the bike made it the three miles
home, no need to test my endurance by pushing it. On stripping
down the piston looked like I'd taken a file to it; scored was
an understatement. Matched by the bore - another rebore, piston
and rings, and a weekend's rebuild.
Back on the road, the RD was great fun to ride after I'd run it
in properly. A bit peaky, due to the mods, and after one Saturday
morning's porting job (copied from an article in Performance Bike)
the revs reached dizzy heights. Nothing below 8000rpm, but from
there onwards to 13000rpm it was just a blur. Countryside and
tarmac just merged to add to the confusion. Once I became used
to it, great fun!
The single front disc with braided hose gave a good feel. I can't
exactly say it was progressive but you always knew what was going
on. Until coming out of my garage one afternoon, at a fair turn
of speed, applied the front brake, started to slow down then all
of a sudden the lever came all the way back to the bars. Stamped
on the rear pedal and stopped just short of the road.
As soon as I regained my nerve I took a look. A small hole had
appeared in the braided hose, looked as though the hose had chaffed
the fork guide. The fun began when I tried to fit a new hose.
Easy to remove, the new one went on a treat, but when it came
to bleeding the caliper, forget it. The caliper was seized solid,
no way I could shift it. Off to the local breaker for a replacement
for all of a tenner.
The new brake lasted for half a dozen pumps on the lever. Drained
the system again, the only area left to check was the master cylinder-
its rubber skirt was split. Yet another trip to the breaker but
at least I was soon back in business.
MOT time again. Yes, I do believe in being legal, which includes
tax and insurance. It's the MOT I hate the most- your pride and
joy's pulled apart in front of you, then the smug git turns around
with that grin. You've failed! This time it's the rear wheel bearings.
Taking the back wheel out was fun. The use of bricks and a piece
of wood to keep the bike upright; no centrestand. On finally pulling
the wheel out the sprocket's side bearing just fell out. I must
admit I never even noticed it was that bad, but it wasn't the
bearing causing the slack- the hub itself had worn away! Chemical
Metal was smeared around the new bearing before it was fitted!
Passed the MOT the next day.
The chassis was next. A nice spray job in red and yellow, which
faded into each other. To give it a real sporting look I fitted
a single saddlle and old seat hump, to which the light and numberplate
were bolted. Overall, quite an impressive pocket rocket.
Fun was had fitting a new set of tyres, although they lasted for
two years. I was quoted a ridiculous sum for fitting the new rubber
to loose wheels. I found out why when the tyre lever slipped,
came flipping back in an attempt to take out my kneecap. Instead
it whacked my shin! Aaaargh! Brought tears to my eyes.
Other bruises came from the time I tried to split an endless chain.
The hammer and punch routine left my fingers well bloodied. Even
when the rivets moved a little, I finally had to grapple with
the oily mess to get it apart. It's worth fitting a HD chain as
adjustment's quite frequent due to the fiery power.
Another year, another MOT. A quick ring of the local dealer for
an appointment only to find the only time available I couldn't
make it. A friend was given the honour of riding the bike there,
only to come back an hour later with a fail. A free retest if
I could fix it fast, the rear bearing gone again. No time for
Chemical Metal. I hammered the boss so that the material spread
inwards, producing a tight fit for the bearings. Nice and tight,
one MOT pass. Soon after that I passed the driving test, the bike
quickly sold in favour of an RD250LC- what else could I buy after
so many happy years on the smaller Yamaha?
Lippy
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