Dennis Noyes Tribute

Eighties motorbikes tests

Yamaha XJ 650

Number ONE

We have tried to find important defects on the Yamaha XJ 650, but it has been in vain. Finally, we can praise without qualifications one of the Semsa Yamaha bikes.   Weighing 218 kilos with 73 hp at 9 000 r.p.m. the Yamaha XJ 650 exceeds the barrier of 200 km/h (124.2 mph). It can do one kilometer from full stop faster than most of the 1000 cc. bikes in the Spanish market, and when we arrived at the bumpy curves it performed like a European. 

The brakes are powerful and progressive, the rider position is neutral and convenient, and the suspension represents an excellent compromise between comfort and stability. Like a GP motorcycle there is no full fairing, and like a sport bike it lacks a bit of general rigidity in exaggerated driving. For the long distance cyclist, this Yamaha may seem a little nervous and short in the power range in comparison with a Guzzi or BMW, and for the hard cores who spend their Sundays in the mountains scraping the toes of their boots on curves, the XJ is somewhat off in comparison to a thoroughbred sports bike like the Ducati Pantah, but long distance riders and the hard core represent a small percentage of motorcyclists, and Yamaha has directed their XJ towards a general and "normal" clientele.

Plus, if the XS 1100 S errs in being massive and not very flexible, or in its profile and “California” position, the XV 750 XJ 650 is compact, relatively rigid and has a line so classical and semi-European that only the oversized headlight (210 mm/8.26 inches) seems to be a little out of proportion.

The return of the 650 cc

The cylinder capacity of 650 cc was, when I started to ride motorcycles, the displacement queen.  A Royal Enfield 710 DC or a Norton Atlas 750 DC seemed enormous, and back in the 1960’s we seriously wondered if a bike bigger than 650 cc was really practical. With a Triumph Bonneville in 1967 you didn't have to fear anyone on a straight run or even in the mountains. The marketing in 1968 of the Norton Commando, however, caused a sensation and a “horsepower war.”  For the first time we read the word “superbike” in reviews, and the Norton Commando, with its isolastic system to filter the vibrations of the 360 degrees twin cylinder engine, established itself as the most prestigious sport bike in the world.

Heading to the Gran Prix de France in 1969 at the controls of my up to then “fast” BSA 650 Thunderbolt, I was passed on the highway by a gang of Frenchmen on Norton Commandos, traveling at a cruising speed of more than 160 km/h (99.4 mph), and I started to dream of having a Norton Commando.

The Norton was the dream of many at that time. The presentation of the then three-cylinder Jumbo 750 Triumph-BSA, followed by the commercialization of the first Honda CB 750 Four, were the most significant events of 1969.   From the perspective of 1982 it is easy to say that the current era of high-powered multi-valve motors began with the Trident, the Rocket and the Four.  However, the truth is that the Norton Commando 750 was still the queen of winding roads and capable of approaching the 200 km/h (124.2 mph) with a little fixing up.

The only bikes that were finally able to keep up with the Norton on the circuit were also European…from Italy: the Ducati 900 SS and the Laverda Jota. Until the arrival of the Suzuki GS 1000 in 1978, no Japanese motorcycle had earned a favorable comparison with the best high powered European bike.

However, the increase in cylinder capacities and the fall of the English industry left us with a big open hole between 550 and 1.000 cc, since the Japanese 750 cc bikes were heavy, wide, not as much fun and less agile than the two cylinder English bikes of the previous decade. Triumph, already had an engine increased to 750 cc.  It carried on, but its noble two cylinder bikes were not offering performance comparable to those of the Japanese 750 cc four cylinder bikes.

Yamaha saw a market for the 650 cc, and its two cylinder of this size took away sales from Triumph, but the first Japanese brand to offer a three cylinder light and sporty bike was Kawasaki.  Its Z-650 was a great decision because it offered the finesse of a three cylinder without the weight of a 1000 cc bike.

For a short time these delicious machines entered Spain from the U.S., but on the proposal of Sermoto this importation of Japanese patent bikes and American manufacturing was stopped and the option of a Kawasaki 650 disappeared from the Spanish market. 

While in Spain we continued with our Guzzi, Benelli, Laverda, BMW y Ducati bikes, the other Japanese brands discovered again the classical capacity of 650 cc; namely Honda, with the CB 650, based strictly on the single shaft CB 750, the next to appear.  However, with the GS 650 GX, Suzuki offered a bike DOHC (Double overhead camshaft) capable of equaling the performances of the fast Kawasaki, and shortly thereafter they presented the GS 650 GX Katana with an increase in compression and an official 73 hp, which far outshined the Kawasaki 650, and with secondary transmission by universal like the Suzuki GS 650 GX normal.

However, the Katana never went so far as to outdo the also new Yamaha XJ 650 DOHC with its narrow engine crankcases, driveshaft with the feel of a chain and noble stability.

This new generation of 650 cc Japanese bikes outweighs the two cylinder 750, 850 and 900 cc bikes  of the years 1970-1976, but improvements in tires, brakes and suspensions in recent years have made these 210/200 kg. (440.0/462.9 pounds) stable and secure 650 cc bikes.

Three European brands have designed 600/650 bikes to compete with the Japanese.  Of these, the BMW R-65 is the most popular, although far from the Japanese in performance.  The most prestigious is the Ducati Pantah 600, the best sport bike of the 550/650 capacity (although it already has a new dangerous rival in the fast, light and relatively economical Kawasaki 550) and the most similar to the Yamaha in concept is the new Benelli 654 Sport (that has a cubic volume of 604 cc).

However, in overall sales and general acceptance the Yamaha XJ 650 with the YICS system of secondary conduits to create a swirling spiral of mixture within the combustion chambers remains the most popular 650 cc at the present moment.

The return to the 650 cc displacement and the great acceptance of motorcycles of this size represents in part a return to bikes being built to a logical size; a change that puts more emphasis on kindness and agility than on gross power.


The XJ 650, however, is a fast motorcycle; the fastest that we tested and with performance comparable to the best two cylinder 850 cc. and even some Japanese 1.000 cc bikes.  The maximum speed with a favorable wind is a brilliant 201 Km/h. (125 mph).  It was reached with the motor spinning at over 9200 r.p.m..  The average going and coming over the same testing track was 196 Km/h (121.7 mph).

I n order to get to the true maximum speed of the Yamaha XJ you have to wear a leather jumpsuit and button up everything, pushing the motor in fourth (around 9700 r.p.m.) and then race-shifting (with only a tap on the clutch) to get the gear.  In the one kilometer acceleration tests from stop I took it a little easy on the clutch and maybe the average of 25.7 both ways could have been a little better with a bit more driving a la drag-race, but even so the Yamaha is the fastest machine in both acceleration and maximum speed that has passed through our section.


The first Yamaha XJ 650 bikes with the YICS system were famous for being very thirsty, using up to 10 liters of fuel for every 100 km of sports riding, and with an average consumption of seven liters per 100 km. in normal driving.  In our constant speed test of 100 km/h (62 mph) and 120 Km/h. (74.5 mph), the Yamaha used 5.3 and 6.8 litros/100.

In a really quick Madrid-Barcelona trip, the average consumption with a cruising speed of 160 Km/h. (99.4 mph) on a toll road with an average of stops and toll booths of 1120 Km/hl was an average 8,2/100.  As for mountain sports driving session the Yamaha barely passed more than 9 liters per 100.

Power Range

I am writing these lines from the point of view of the road tester without having looked yet at the results of the test-stand done by Andrés Ruiz, but independent of the bank results, I would say that the Yamaha has a kind of emptiness over 6000 r.p.m.; with useful power from 3000 to 5500 r.p.m. (provided that you don’t hit the gas too quickly); a zone where the motor doesn’t respond happily, between 5500 and a little over 6000 r.p.m.,  and a progressive increase of power that begins at 6500 r.p.m. and continues until  9500 r.p.m..

The maximum torque, according to the factory, is 5.5 Kgm at 7500 r.p.m., and in order to accelerate cleanly with the throttle open with the XJ, you always need a minimum of 6500 r.p.m..  This means that on a quiet cruise of 120 Km/h (74.5 mph) at 5500 r.p.m. you have to shift down a gear to advance quickly and two gears for sudden acceleration. If you drop two gears running at 120 Km/h (74.5 mph) at 5500 r.p.m. in fifth, you will find 7800 r.p.m. on the accelerator to power and you can pass a long TIR truck very quickly. If you shift down a single gear you'll be at 6900 r.p.m. in fourth, with a clear and immediate response from the engine.

The only disadvantage of the XJ 650 over 1000 cc bikes is that the rider has to keep the needle on the dial above 6500 r.p.m. provided that you want to accelerate quickly.

In spite of having 73 hp and a very high maximum speed, the Yamaha does not appear to be powerful at first glance.  If you are used to big bikes or two cylinder bikes from 500 cc. to 750 cc, the Yamaha will not give you a ferocious motor sensation.  Plus, if you are not used to the feel of the Japanese short stroke four cylinder bikes, it is going to be difficult for you to pick up the trick of making the motor scream at high speed..., and the thing is that this what the XJ wants..., more and more r.p.m.!

Don't worry about mechanics, since with a 52 mm. stroke (2 inches), the Yamaha at 10,000 r.p.m. is only turning a quiet linear 17.3 m/s piston speed, while a Ducati Pantah 500, with 58 mm (2.2 inches) stroke, is already approaching the red zone of truth of 20 meters/second linear speed of piston to 10.000 r.p.m. With the Motorcycling Series Pantah, I have 'official authorization' of up to 11,000 r.p.m., Francisco Castellanos “with checked flags in sight and Montesa in front,” and this, my friends, means 21.3 meters/100 km with a series engine. So you not have to worry about the Yamaha high speed rotation. As my friend and former sponsor 'Big Jim' Kitts always said, “Listen, moron, considering R.P.M. without taking into account the crankshaft stroke produces a meaningless statistic!” However, the difference between a Japanese series bike and an Italian series bike is that the Japanese do not sell you bikes that can go beyond their mechanical limits on long runs, while Italian engineers, especially in Ducati and Laverda, sell you a bike equipped with an engine capable of suicide if you do not respect the limit.

With the Yamaha, the real limit of the Pistons and connecting rods is at 2,500 spins short of the 9,500 r.p.m. red line and engine is out of breath at 10.000 r.p.m., and at this regime I simply never noticed the floatation of the valves.



It seems like a lie that the XJ 650 and the XS 1100 S come from the same factory, and the truth is, in fact, that we are just used to the “European factories whose ranges are coherent.” A Ducati is always a Ducati; a Laverda is always a Laverda, and a BMW, of course, always has the same patented touch of the German factory.  However, this is because each one of these small factories has a concept that is very much their own (except for Benelli) of what a motorcycle should be.

Fabio Taglioni would hang himself before designing a three cylinder transversal with secondary transmission shaft.  Piero Laverda would go to work with his uncle in the farm machinery factory of agricultural machinery before building a 'two-stroke' road bike, and Morini would close before manufacturing a transverse two-cylinder bike... However, a Japanese factory does everything: two-stroke sports bikes, single cylinder four stroke bikes, scooters, mowers, tricycles, six-cylinder Superbikes Grand Prix machines and even guitars.

This is why Yamaha has the best and some of the worst bikes in its range.  The XS 1100 S has received so many criticisms on our pages that it almost makes me sad, but there is no impartial test rider in Europe who justify the  XS 1100 S as a sports bike in comparison with the Honda CB 1100 R, the Suzuki GSX 1100 Katana or the Kawasaki Z 1100 GP.

Likewise, the Yamaha XJ is in the general opinion of European testers, the best 650 Japanese bike at the moment, followed at a discrete distance by the Suzuki 650 and with a big advantage over the Honda CB 650 and the Kawasaki 2 650.

A large part of this advantage is due to it robust and powerful motor, although Yamaha y also stands out because of its stability and braking. 

By mounting the alternator on top of the gearbox and behind the cylinder block (it is controlled by a chain from the crankshaft) Yamaha allows you to handle steep slopes without scrapping your shoes on the asphalt and by having the exhausts pass under the frame they avoid their scraping on the ground as well.  The Yamaha, whose Bridgestone tires have a good grip (it is not true that Japanese tires are so bad; that was before) allows us to reach the highest level of grip without anything other than the folding foot pegs touching the ground.

In an initial test done on cold asphalt in England last December, I liked the XJ and I liked it a lot!  However, I still had a few doubts about its stability on the bumpy and hot roads of Spain.  I no longer have any doubts about it.

The Yamaha performs very well, even in sports riding.  It doesn’t shake a lot, and only sometimes wobbles, but to place it within the national perspective, I would say that it is noticeably more stable in quick curves than a BMW R-65 and capable on the shakedown on circuit without any important problems.  I saw a 650 XJ in Madrid with fork brace, but it has to be the bike of a hard-core, super demanding burnout, because as a street bike, the Yamaha has excellent and strong suspension with its sturdy double-cradle frame and rigid fork.

In sports riding you have to brake a little later in the entrance to slow curves to avoid bouncing, but the truth is that the bike is easy to handle when going quickly…easy to handle at the limit and it inspires confidence in its rider.

From the first moment when I got on the XJ 650 in England I was certain that this Yamaha would be the bike that three quarters of the cyclists in Spain had waited for so many years.  For that expert who scrapes the exhausts in the mountains (it’s possible, but difficult) this bike will be fun and virtually indestructible.  For the long distance traveler who does twelve hour days with a passenger and luggage, the Yamaha will permit high cruising speeds and reasonable fuel consumption..., although I don’t know if the stability while going straight will be adversely affected by fixing semi-fairing to the steering column.  I don’t want to repeat the comments that I made about the initial test in December…, suffice it to say that the finish, instruments, controls, locking gas tank and toolkit are not inconspicuous on this excellent machine.

A couple of days ago I was talking with a pseudo-purist with many prejudices who wanted to hear me speak badly about the Yamaha XJ 650, thinking that he would find in me an anti-Japonese test rider willing to trash all oriental bikes.  He was disappointed.  Nobody has an exclusive on the construction of good bikes…not the Japanese…not the Europeans…not anybody.  


All things considered, except for its lack of response at medium speed, the only flaw of the Yamaha XJ 650 is its price of 580,000 pesetas (3,485 Euros), which, for reasons which we have explained several times, seems excessive.

This bike should have entered the market at around 500,000 pesetas, because 580,000 (3,005 Euros) is equivalent to a Ducati Pantah at 875,000 pesetas (5,250 Euros) (basing it on the differences in price between European and Japanese bike in the countries of the Common Market.)  The Pantah, according to new importers, will enter at 650,000 pesetas (3,906 Euros) (exactly the fair price that we calculated for it during the December trial of the Yamaha XJ).

The face that Semsa is going to sell them all proves them right commercially, but I continue to think that another pricing policy would have been more beneficial in the long run since what should interest the Japanese of Semsa-Yamaha more than anything is the good image of the brand in a country with a growing affection and good weather…, a country that has been called the new California of the motorcycle.

However, those of you who have waited so many years to have the option of a good Japanese bike, have it here.  Although the four cylinder transversal was from the beginning until now the GP bike of Guera and MV Agusta, the great feat of the Japanese factories has been to make viable commercial versions with four cylinders in line. The transverse four cylinder engine is wide and requires a high center of gravity, but it is robust with very low vibration and with extraordinary performance.   Plus, of all the modern fours from the Honda 400 cc. up to the huge and powerful 1100 bikes of today, the Yamaha XJ 650 is agile, fast, comfortable, stable and suitable for everything and almost everyone, is the most fun and enjoyable four cylinder bike that I've ridden so far.

It’s a great motorcycle, the “number one” bike of the Yamaha range in Spain.