I like to go everywhere in the UK on a motorcycle. People call it a small place but there are still vast swathes of country to explore. On the right machine. Some huge Gold Wing type tourer would be far too expensive to run. A race replica could only be ridden at speed, which would make the country too small.
Middleweight fours have lots of virtues but when they are practical they also become rather bland and boring. I will admit I was tempted by a Honda CB400F. What I really wanted was a good 500cc twin, just like the British industry used to produce in the sixties but with Japanese type reliability. There were some possibilities but not for the £300 I had to spare.
Enter a 1980 Yamaha SR500 into my life. The owner, some kind of ex-miner, said I could have it for £250 if I could start it first kick. I'd owned a Panther single in the depths of the past, compared to that long stroke bugger with marginal ignition the SR was a cinch. The Yam's a compact, light and, erm, noisy little motorcycle!
Nearly every one in the country has been modded with a pattern megaphone that makes them sound like an old racing Goldie on full cam. The motor's relatively advanced with a single overhead cam but lacks any kind of balancer, an omission that more or less limits the engine to 5000 revs, especially if, like the one I'd bought, the mileage was over 30,000 miles.
The bike was vaguely standard in rat black with some sensible touches such as Girling shocks, Avon tyres, gaitered forks and electronic ignition. The saddle looked like it'd been robbed from an old Triumph but I wasn't complaining as the padding and shape were excellent. The handlebars looked like they might've come from the same source, though the rear-sets seemed out of place on a machine that was reluctant to puff up to more than 75mph.
I did discover, though, that the riding position proved very comfortable indeed, as much as 500 miles in a day possible. In fact, on one trip from London to Inverness I kept catching up with a gang of youths on race replicas. They would ride like lunatics for half an hour and then have to spend a similar amount of time resting up. I just blatted up the countryside at a more or less constant speed, equalling if not bettering their average velocity.
For long tours I had acquired a five gallon tank which gave a much more adequate range than the stock tank. Used mildly, which was the only way I rode the bike, the SR was turning in 65 to 70mpg. No doubt the K & N filter and straight through exhaust allowed more efficient running than stock, contributing to the excellent frugality (for a modern machine, anyway, my old British bikes would do 70 to 75mpg at similar speeds). For someone on a limited income such factors can make a huge difference to the amount of mileage covered. As all the other consumables wore mildly (I'd fitted a Scottoiler) I was quids in.
The SR proved to be a bit of talking point with the old boys as it wasn't instantly recognizable as a Japanese bike under the road grime and implacable alloy corrosion. Also, I was offered two SR500s for free! One had seized its gearbox, resulting in a slide down the road. The other had snapped its camchain, the valves and piston merging into a solid lump of super-heated alloy and steel.
As both demises occurred at around 45000 miles this had me a little worried for the future of my motor. The key to long life is 500 mile oil changes! Another common SR weak spot is the piston and rings, but the enforced low revs and clean oil, I hoped, would eliminate that particular horror. I treated the engine with Slick 50, which apart from any other benefit meant I was getting 70mpg all the time!
With all the spare chassis parts my running costs were slashed even more. However, both bikes were stored for a couple of years. Guards, tank and even the frame in one case were rusted through. I was more than happy, though, with a stack of pads, shoes, cogs, tyres and almost one complete set of good engine parts.
Insurance becoming ridiculous meant I was only paying out for third party, so I became even more reluctant to clean the bike. The starting was, of course, a bit of a deterrent to glue sniffing youths sporting stolen trainers. I would really have loved to fit a hidden switch that advanced the ignition, causing any villain who tried to kick the old girl into to life to receive a broken leg whilst being shot through the air by the kickback. That proved too taxing a problem for my mind, instead I incorporated three switches that wrongly positioned would sound the horn rather than turn the ignition on.
That was fine until a lead shorted out, leaving the horn blaring away as I was plodding through Chelmsford. Now, I'd hidden the horn and wiring away so that no-one could pull the leads off. In the end I had to tear the battery's lead off. Any modification to the SR has to be as well planned as it is built to survive the untamed primary vibes.
More modern machines have much lighter reciprocating masses and a balancer that redirects rather than absorbing the remaining vibration, though even these singles are not entirely smooth they do lack the destructive urges of old beasts like the SR. Bear in mind, that when balancers are added efficiency diminishes and fuel economy goes to pot. Some old extreme British singles ruined economy by having so much vibration that the fuel frothed in the carb!
As well as limiting top speed, the vibes also caused a few on the road failures. The only one that needed the AA relay was when the alloy fuel tank split. Somehow, the engine swamped in petrol didn't go up in flames. Despite lots of rubber mounting, clenching the tank tightly with my knees revealed a fury of grinding vibration!
It'd also ruin rectifiers, bulbs and exhaust down-pipes. The latter would make a tremendous racket and leave a 2000rpm power band in which to ride, but invariably allowed me to get home. I took to welding quite thick steel plate around the cracks, ending up with a 50lb exhaust, as the ones from the two spare bikes were rusted through. Surprise, surprise.
It might be expected that I had a lot of trouble from the engine, but with 63000 miles now on the clock it is still going strong. The gearbox was always nasty but didn't become any more intractable. At 40,000 miles I fitted a new camchain and renovated tensioner, and cleaned off all the carbon on the piston and head. The engine is very noisy and needs the valves set-up every 500 miles, so a head swap will be in order soon. I've already renovated an old one in readiness.
The SR had 30 horses when new, little better than an old 250 twin. There isn't a hint of a power band and not even an impressive flow of torque. What it will do is hit 70mph in a reasonably short time and hold on to that speed against strong winds and up steep hills. Or even two-up, which is rather a rare occurrence. The best way to ride is to find fifth gear as quickly as possible, let the engine plod along. Below 30mph in top the chain feels like it's trying to jump off the sprockets, needing some gentle but firm footwork to find second or third. Out on the open road the bike was dead easy to ride and very relaxed to cruise upon.
The chassis was nothing special. With its stiffened up suspension there were hints of old British bikes. Anyone not used to such things would find the ride rather rough going but it didn't bother me. The best that could be said for the chassis was that it hardly ever needed any attention. One caliper rebuild and a set of swinging arm bearings were all I had to do. With that kind of easy life I could have forgiven the chassis a lot. But there was little to forgive, it went where it was pointed, heeled over without threatening to spit me off and was easy to chuck through bends.
All of this doesn't point out that the character of the Yamaha was such that it was always a joy to ride. It's hard to put a finger on quite why such an old, slow and vibratory machine was so enjoyable that even after 500 miles in a day I sprang off the bike with a large grin on my face. One of the great mysteries of motorcycling!
Charles Longman
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The day was cold and frosty when I first saw a Yamaha SR500. Its matt black colour seemed to take whatever little heat there was out of the day. The poor old thing looked in desperate need of a little bit of TLC. Parked outside a Southampton dealer's that had a bad rep twenty years ago and had somehow survived into the nineties. There were a lot of dealers like that, the criminals prospering whilst the good guys went out of business.
'Can't get her to start, mate,' said the large lout in overalls. 'Do you want to make an offer for the bloody thing?'
I tried the kickstart. She rolled over like there was good compression. Turned the ignition on, gave a few pumps. Dead meat.
'£200?' I asked.
'Sod off, mate, what world are you living in. Can't buy a new set of consumables for that. £500!'
I laughed, said forget it. The gorilla grabbed my arm, squeezed, screamed,
'You're not giving me hassle, are you, mate?'
I tried to shake him off and walk away. He hopped alongside for a good twenty yards, trying out all the swear words he knew. Finally freed, I turned to walk away and he went to slap my head, but I moved out of the way. He went flying, I increased my pace, left him screaming abuse. What a sorry fellow.
I didn't buy that SR but the next one I saw I did purchase. It was in a similar sad state. Another reluctant starter, when it finally fired there were clouds of smoke and a rattly engine. Crunched through the gears and wobbled up the road during the test ride.
'How about two hundred quid?' I tried again, keeping the bike between owner and myself - I'm a quick learner! The guy whipped the notes out of my hand as fast as a druggie offered a fix, threw the doc's at me and slammed his front door shut. I checked the frame number against the registration doc just to make sure it was all in order. No problem.
I chanced riding the bike home. It was like some fifties relic, coughing, smoking and vibrating like a good 'un. If I'd been old enough I would've had hot flashes back to my youth. But I was too young for that, having grown up on RD250's and the like. Happy days. The SR made it the 35 miles to my council hovel but my watch was never the same again.
The SR500's the last of the real big thumpers. Oh, there are plenty of big Jap singles but they all have technological advances like balancers, watercooling and four valve heads. None of that for the SR, it was just like a BSA B44 or Enfield Conti except that it had the benefit of an OHC...mixing severe primary vibes with pushrods is just stupid. Believe no-one who tells you otherwise.
Thus the SR's easy to strip down except for the well known seized in screw problem. Hammer and chisel routine for the most part, the odd one needed to be drilled out. Gingerly. Used barrel, piston, cylinder head, carb and gearbox selectors were the major components needed.
When I was sure that the engine was going to work I set to sorting the chassis. Everything apart from the frame was merrily rotting away. I replaced nothing, though, repaired where necessary with steel sheet, welding torch and a little artistry. Took a couple of weeks of pleasant night work but I enjoyed myself and it cost next to nowt. And the bike looked rather splendid after I was let loose with my electric spray gun and a can of dark blue paint.
Total cost, including purchase, was £325, the engine parts making up most of that. One of the downsides of SR ownership, and the reason they didn't last long in the UK, was the lack of an electric starter. The kickstart's not particularly well levered and it takes good leg muscles and a beefy frame to back it up. My engine ran to electronic ignition, but this didn't entirely eliminate the chances of a kickback or the odd day when the carb tried to turn into a flame-thrower.
As winter deepened, the starting became so precarious that a bump start was often needed. The bike wasn't heavy at 350lbs, so it wasn't much of an effort to run alongside and leap on. Warmed me up nicely. Not so nice was the way the engine cut out at low revs and then refused to start again for at least five minutes! The cagers went berserk at this interference with their crawling forward at 2mph!
One thug, equipped with a four wheel drive tank and bull-bars, decided to give me a push. This would've been very helpful had not his bull-bars destroyed the back of the bike, whacked the tyre, which then flipped us sideways. He went heavy handed on the horn and would've flattened us had not I hurriedly picked myself up and dragged the SR up on the pavement. It's surprising what fear and adrenaline assisted muscles can achieve. I ran after his car, kicking in his back lights, an expensive looking cluster.
The SR cost a fiver to sort out via a friendly breaker, and some hammering and welding of the back guard. The Yam's fairly rugged (when not rusting away) and can happily withstand being thrown down the road a few times. I just wish I was as tough, suffering massive bruising to arm and knee - I eventually opted for body armour, which encouraged a fearless riding style.
The SR was well suited to traffic bashing (as long as the throttle was blipped at junctions), being admirably narrow and full of punchy low rev torque. Admittedly, the engine ran out of power come 75mph, though it could be thrashed up to 90mph - at the cost of eyeball rotating vibration and an engine that sounded like it was about to explode.
There were a couple of areas lacking in inspiration. The front disc was typically Yamaha - naff in the extreme! Didn't have much more power than a good TLS drum, didn't want to work in the wet and a bit of salt on the road was all the excuse it needed to seize up. Also, the undoubtedly high mileage front forks had sod all damping and responded to heavy-duty springs by becoming all coil-bound when the roads turned rough. Nothing a real man couldn't handle, of course, but liable to have a recent graduate deposited in the nearest ditch.
Which is where I'd have liked to dump the SR when the top end started rattling again after approximately 6000 miles. Mileage was vague because the speedo kept breaking down. Either the cable snapped (too short, I later realised) or bits breaking up inside.
The Yam has a single overhead cam that has to operate a mere two valves via rockers. You wouldn't think this was too much trouble to design, would you, but my replacement head was losing chunks out of the cam lobes, with consequent impossibility of setting the clearances accurately. The spare cam, as luck would have it, was in better shape and shoved in during an afternoon's worth of spanner wielding.
Unfortunately, I didn't put in a new head gasket, which made it gush out oil like an old Royal Enfield single. New gasket, more work and all was well with the world. Well, it wasn't really. I was a bit fed up with the unpredictable starting and lack of out of town performance, as well as the patches of rust that kept coming out of the metal despite my best efforts.
I must say the bike shined up nicely enough, encouraging me to put it in the paper for £1500! Not many phone calls but after a lot of haggling I off-loaded the would-be classic for £1250. A nice meaty profit that went towards buying a nearly new GB250, on the UMG's advice. Much to my shock and horror for once the press wasn't lying and the little Honda was in all ways vastly superior to the Yamaha. Okay, it cost a bit more and is a lot newer (if you must, you can buy new SR400's!) but it just shows that singles work much better as 250's than 500's, down to the inbuilt limiting factor of their vibration. I know, you don't want to believe this but it's true.
Harry Trent