Riders’ Reports…

Yamaha XS250
Yamaha XS400 DOHC
Yamaha XS250
Yamaha XS400
Yamaha XS400
Yamaha XS400 Special
Yamaha XS400
Yamaha XS250
Yamaha XS250
Yamaha XS400 DOHC


Yamaha XS250
SOU 312S, a silver example, first appeared on a front drive a few streets away, having been replaced by a CX500. The XS250 was in a poor state when parked, several months rain took its toll and each time I passed the house with the dog, it looked worse, but I still thought it would make a good replacement for my Suzuki GT185.

When I finally found the owner at home, on the sixth attempt, he said I could have it for a tenner as it was only fit for scrap. The only good points were a decent pair of Roadrunners, the rest was dog rough….the motor was solid so I convinced myself that the kickstart was at fault.

Removing the right-hand engine cover revealed a perfect kickstart mechanism, the damn primary gear would not turn. Left-hand cover off, the alternator would not budge either. Off with the cambox cover, the camchain had to be sawn through, the head removed to reveal the left-hand piston melted into the bore. The piston was eventually freed from the bore using impact technology.

An engine was purchased from a breaker which had a sound top end and the best bits of each engine were combined, complete with the odd helicoil and bodge. The frame and cycle parts were resprayed, both discs skimmed, a caliper replaced from the local breaker along with many other items and a wheel not about to crack up installed. It looked really great when reassembled.

I liked its simple lines. It was a very straightforward piece of design work – a SOHC vertical twin with pistons moving up and down alternatively, not a balance shaft in sight. It had convention twin rear shocks, cast alloy wheels, discs at each end and an air of ruggedness.

It spluttered into life but was obviously not right. The carbs were cleaned out but the main bearing and big-end shells were making a bit of a row, so these were replaced and the motor reassembled again. It ran nice and quiet, passed the MOT first time. First problem was an unreliable tickover, the bike needed much fettling every 100 miles as the timing kept going out.

Performance was not startling. Although it could be run along at low revs the power didn’t start to appear until the upper reaches of the rev range, and even then it would not pull your arms out of your sockets. Top speed was somewhere around an indicated 90mph, it was much happier cruising at 70mph, where it would buzz along all day without much of a care in the world.

Handling on worn suspension was fair, it never seemed likely to throw me off in the curves and save for the odd being of weaving or wobbling when the road surface deteriorated was stable enough to be pleasant on motorways. I never rode the bike to extremes as I wanted to maintain my grip on life.

After about 1500 miles I dropped the bike exiting the M4 roundabout with my teenage son on the back. The shame of it. Cuts and bruises, ruined jacket and scrapes on the bike. I couldn’t even have a good swear with the lad about it. The gear lever was bent and jammed but the following cars stopped to assist and get the bike off the road. A borrowed Stillson wrench straightened out the gear lever and the motor fired up okay.

The cause of the fall was an oil slick. I fixed the bike up easily enough but I had lost confidence in it. An Avon Supreme front tyre and a new set of headraces helped instill some bravado in my riding. The points kept wearing out rapidly and I had to retime it every weekend – I thought this was only necessary on old British iron – but at least the miles were piling up.

I was doing 1500 mile oil changes with a new filter at 3000 miles. The chain was washed in petrol/paraffin then boiled in Linklyfe every 1000 miles, sprayed every weekend, along with a couple of strokes of the grease gun to the two swinging arm nipples. Both sets of pads were dismantled every service and reassembled with Copaslip. EBC pads were an early improvement and covered 5000 miles before being transferred to the rear with the new set on to the front.

At 31500 miles, 7000 on the rebuilt motor, I bought a new engine from a school that had been given two by Yamaha for a project. At £100 it was too good to miss. It still had the need for frequent ignition timing adjustments. Piranha ignition at 36300 miles gave a much crisper motor with better throttle pick up. Plug gaps had to be closed to 0.025 to cure a cold misfire at tickover.

A few weeks later I replaced the other Roadrunner. The Supreme on the front was placed on the back and a Michelin M38S was fitted to the front. The Roadrunners did about 5000 miles each, the front Supreme had done 7000 miles without significant wear.

The bike was really running well, I believed the problems were behind me and I could start planning some long runs without the need for constant maintenance. Comfort was okay for a 100 miles at a time. The seat was the first to give problems, not helped by an imperfect body posture resulting from forward mounted footrests. If you wanted to ride flat out for long distances the bike would quickly become very tiring.

I was able to swap from four to two star fuel with no ill effects once the electronic ignition had been fitted. The bike averaged 80mpg which I though very reasonable, even a hard ride down country lanes didn’t dent it too much, with 72mpg being the result. One up for lack of balance chains, eat yer heart out Superdream owners.

One dark and rainy night in March ’89 as I’m plonking back from Salisbury across the plain, doing about 50mph along a nice curvy bit the bike loses power…..the rear disc had seized on. Slackened off the master cylinder pushrod, the brake freed off and the journey home continued. A weekend strip down revealed a soft seal ring and some corrosion on the piston. A new seal and polished up components appears to have solved the problem.

Some useful suggestions for users – Motocraft Ford plugs (AG22C) work fine, cheap against NGK; Ford 15W40 oil, good and cheap; Piranha ignition, well worth the money; Avon 180 Supreme tyres, good grip, last well and inexpensive, M38S ditto; EBC pads much better than stock; Baja foam grips soak up the vibes nicely.

To conclude, if you are prepared to invest a little time to maintain and service the beast I don’t expect anyone to be disappointed in an XS. Cheap and cheerful with a plentiful supply of parts, both used and new, you can still pick up a runner and another for spares for next to nothing. Worth looking out for.

Derek Anstey

Return to Contents for Yam twins


Yamaha XS400 DOHC
I’m an avid air cooled four stroke fan, so when I saw the little Yamaha I fell for it. You don’t see many around and it should not be confused with the fairly awful OHC version. My bike has a nice lump of DOHC vertical twin alloy engine held in a spine tyre frame with monoshock rear suspension, Styling is neat, surely the best looking air cooled twin?

The bike already had 20,000 miles on the clock when I bought it. I knew the previous owner well and felt sure that it had been well looked after and mildly used. £300 changed hands, not too bad for a B reg machine. There were some problems. The most noticeable shot front wheel bearings allowing half an inch of side play. Even so, I was still able to ride it home and the bike was light and flickable.

Also in need of replacement were the exhaust (an £80 Motad saw to that) and a badly split seat – it had a plastic base and I was able to fix it with a combination of vinyl and a staple gun – plus a £30 sprocket set and a new front tyre while the wheel was out to replace the bearings.

The most impressive thing was the handling. With a set of Metzelers on it could be leant over to quite wild angles without anything touching down. That combined with a responsive motor meant that through the curves it could actually keep up with a mate’s LC350, much to his annoyance. The bike pulls like a particularly pokey single up to 5000rpm and shifts like a bigger bike from then on. You can potter around in a relaxed way or scream the engine to the redline and burn off mild middleweights like GS550s.

Where heavyweights have to slam on the brakes and back off the power, the XS can be hurled through bends with nary a moment of concern, thanks to a stiff frame, good suspension and the excellent tyres. The suspension soaks up most of the bumps with ease and never lets the bike get seriously out of line. The rear monoshock is very similar to that fitted to the DT400MX and, indeed, combined with a seat that perches you on the bike rather than in it, the XS often feels like being sat upon a big trailster.

Braking isn’t perfect. A caliper design shared with the LC ensures that. It has a bloody awful pin which hold the pads in place, it takes a week’s soaking in Plus Gas, a blow torch and an allen key attached to a socket wrench to remove the damn thing.

Thank god there’s only a single disc to maintain, two of the things would have me rushing out to buy a sledgehammer. Wheels are cast in a not particularly attractive eight spoke pattern, but at least Yamaha resisted the temptation to fit a rear disc; instead there’s an excellent drum brake that combines the necessary power with lots of feedback.

In 10,000 miles there have been no engine problems. It never uses any oil, although I change it religiously every 1500 miles and the filters every 3000 miles. I use vacuum gauges to set the carbs myself every 5000 miles and had to do the valve shims once, after 6000 miles. Other than that, nothing needs touching, the camchain tensioner’s automatic and the ignition trouble free electronic.

My only concern with the electrics was that the self cancelling indicators stay on for a little too long in town, but they are fine on motorways and the like. I did notice that the brake light only worked off the front brake. Neither the excellent headlamp bulb nor the twin bulb tail light have blown and general vibration levels are low enough to make them not worth writing about.

Running costs are very low. Even the rear tyre lasted for 10,000 miles and the front didn’t seem to wear. Chain and sprockets have done 10,000 miles and only seem a quarter worn out! Rear brake shoes are probably still the originals judging by the lack of wear and I haven’t had to replace the pads yet either.

The bike does not disappoint on fuel economy, either. It’s possible to better 75mpg if ridden mildly but still fast enough to see off most cars. I have never got worse than 60mpg and it’s very easy to do 65mpg, giving a range of around 200 miles before hitting reserve.

The Yam has been used to commute back and forth to work 50 miles a day, six days a week, and also for weekend work that often involves doing 200 miles in one sitting. The bike takes everything in its stride, although it obviously won’t give the same grin inducing acceleration and ton plus excess of the 600cc race replicas, it has a nice balance of qualities that must appeal to anyone who uses a motorcycle as his or her sole means of transport and wants enough stomp to keep the fun factor going.

The only real question about the XS400 is just why Yamaha never promoted the bike or imported more than a few into this country…..could only be it cost too much.

G.D.Jones

Return to Contents for Yam twins


Yamaha XS250
”Look, mate, I don’t know anything about the heap, I just want it out of garage, like yesterday.” There were worse ways of being introduced to a used motorcycle, at least it promised cheapness. The bike turned out to be a Yam XS250, covered in rust and refusing to start. He was vague about how much he wanted, so I offered fifty quid, eventually settling on £70.

It was a long push home, but a little less hassle after I’d removed the front caliper and drive chain, both of which were later to be found beyond help; no great surprise there. The rest of the chassis looked in just as rotten a state, but to my surprise responded well to my cleaning efforts.

The engine turned out to have no spark at the plugs. Something was very definitely getting through to the HT leads judging by the shock they gave me. It reminded me of my mate’s highly illegal stun gun, which put out a 6000 volt shock. He amused himself by attacking stray dogs, they usually ended up on their backs, twitching wildly, kicking their paws in the air. The shock from the Yamaha was not quite that bad, but it persuaded me that a new pair of HT leads, spark plug caps and plugs were necessary.

Once these were fitted, after about fifty kicks, the motor finally stuttered into life on one cylinder. A bit of frantic effort with the choke and throttle turned the engine into a twin, albeit a rather reluctant one. The smoke out of the rusted exhaust finally cleared and the engine settled down to a 1250rpm tickover. Next tricks, track down a used caliper and buy a cheapo chain.

The first outing was startling for the sogginess of the ride and the paucity of power below 6000rpm. Wringing the engine’s neck finally extracted some go but it felt more like a restricted 125 than a 28hp OHC vertical twin. I thought, what the heck, at least it was still running without any nasty noises. Beggars could not be chosers.

The first weekend I was ready for a gentle amble from London to Birmingham and back. Minor roads all the way, naturally. The Yam had other ideas, refusing to start for half an hour until I took the plugs out and warmed them in the oven. Once clear of the great city, we settled down a reasonable 70mph along some deserted A-roads (it being only six o’clock in the morning).

The first trauma was running on to reserve only to find that it didn’t work. Much shaking of the bike back and forth put just enough in the main tank to get me two miles down the road to a deserted petrol station. The owner rolled up ninety minutes later and hoped I hadn’t been waiting for too long!

About fifty miles later, the second problem turned up, the bike cutting out on the right-hand cylinder. Riding a 25mph, 125cc single didn’t exactly fill me full of the joys of life. Combined with the wrecked suspension, it made for some wild wobbles through the bends when the second cylinder chimed in. I poked around at the HT leads to no avail, but after ten miles of anarchy it started to run properly again.

The handling was predictable in that every time the front wheel hit a bump it would cause the Yam to bounce all over the road. I had already noted a little play in the swinging arm bearings, so was not surprised to find the back end joining in, especially in the bends. There was nothing especially frightening about all this, it was just a matter of keeping hold of the bars and piloting the heap through the worst of the shakes.

Birmingham eventually came into view at about midday. My body was in a pretty wretched state, I had to stagger around the city centre for about an hour before I fully recovered. The Yam refused to start when I returned and there was no-one I could ask to borrow an oven. It took about two hours of wandering around to find a bike shop that stocked a new pair of plugs. I wasted another hour when I found I’d forgotten to pack the spark plug socket.

With new plugs fitted the motor fired up first kick and I collapsed with relief over the bars. It was nearly five o’clock by then and I would have to ride home part of the way in the dark. The first bit of the journey, around 70 miles, was a breeze, with the engine running with remarkable eagerness at the top of its rev range. With a bit of a following wind, it was able to put 90mph on the clock with no sign of any strain.

When I switched the lights on, one cylinder started cutting out again. As darkness fell I was not amused to find that the lights were pathetic, hardly fit for warning other drivers of my presence. I was down to a 25mph crawl for most of the journey. Eye strain soon set in, making me imagine there were dead dogs in the road and nearly running off the tarmac when blinded by oncoming vehicles. By the time I reached my abode, the rear bulb had blown – the first I knew of it!

The next day I found that the bulb hadn’t actually gone, one of its wires had fractured in half and I was lucky it had not shorted out on anything. This led me to the conclusion that rotten wiring was affecting the ignition circuit. An afternoon was spent putting in some new wires, but it also revealed a battery full of white corrosion, so more money was blown on replacing that. I was beginning to think it was impossible to win.

I was encouraged by the way the engine roared into life first kick. On the test run everything was fine, so it was time to use the bike instead of public transport for getting to work. The next morning I ambled down to the XS – yes, you guessed, refused to start until I did the spark plugs in the oven trick. Luckily, I made up time on the run into work so didn’t turn up late. Dinner time I bought a new set of plugs in case they were needed in the evening. Plugs with a life of less than a 100 miles was going to work out expensive. Typically, the damn thing started first kick.

It ran out of fuel again, but I was near to a petrol station this time. Economy worked out at around 65mpg, which, as I was thrashing the machine most of the time, was okay by me. That night I took the petrol tap apart and cleaned out the crud in the mesh on the reserve half of the tap. It was still dangerous, though, reserve not good for more than five miles, but it was better than nothing.

For a couple of weeks the engine settled down, starting from cold reliably and not cutting out on the road. After a really vicious rainstorm all the hassles came back. Three days later not even new plugs could persuade the engine into life. I simplified the ignition wiring and put in a pair of car coils, not willing to pay the ridiculous prices demanded by the Yamaha importer. It was still a reluctant starter from cold but ran reliably enough once warm.

My problems didn’t end there. The suspension had become even more worn, the wobbles threatening to throw me off each time I tried to run the bike through a bend. New swinging arm bearings helped but it was the forks that were in a really bad state. The stanchions were pitted beyond help, the fork seals long since dead and the springs so soggy that all the travel disappeared as soon as I sat on the bike.

An RD front end with a similar wheel was on offer at the breakers for a hundred notes. After I’d explained that this was more than I’d paid for the XS, he let me have it for sixty quid and threw in a pair of shocks off an XS400. I had some fun and games fitting them but it was worth it.

I can’t say that the XS felt like a thoroughbred but most of the wobbles had disappeared and it actually felt safe to lean more than a few degrees off the vertical. If anything, it was a bit too stiff, giving my spine a real going over when the road turned very rough. I could live with that in exchange for the improved handling.

The next few months went by without any spectacular incidents, although I was not too overjoyed to find that the new battery had boiled itself into a premature death. Then I had an accident. I had perhaps become overconfident, as the RD’s disc was brilliantly effective, compared to what I was used to. I had developed a spectacular cut and thrust technique in town traffic that drastically reduced my commuting times whilst giving indignant car drivers heart palpitations. One of these cagers did an unexpected right turn that not even the most powerful front brake in the world would have avoided.

The result was that the XS’s front wheel was embedded in the side of the car and I was thrown off the bike with such force that I cleared the offending cage to land on top of some other poor fool’s roof. Judging by the size of the dent my helmet left this absorbed most of the shock. I was a bit dazed but still coherent enough to refuse to go to hospital for a check-up, much to the annoyance of the ambulance crew and police.

The car driver reckoned it was obviously my fault for riding down the middle of the road at an obscene speed. I protested my innocence, naturally, but have to admit I was doing 50 to 60mph! The XS had wrecked its front end but was otherwise okay, so after all the details were taken I let the AA take the wreck home. There I put on the old front end and decided to sell the bugger before it did me a permanent injury.

I was lucky, insurance rates had just shot up to ridiculous levels for the big stuff, making 250s suddenly popular. I put the XS up for 350 sovs and was deluged with desperate phone calls. Had no problems off-loading the Yam, despite the way it shook its head and wandered all over the road. I didn’t feel the least bit sad to be shot of the heap.

Terry Collins

Return to Contents for Yam twins


Yamaha XS400 DOHC/span>

yamaha-xs-400-dohc-13