Dennis Noyes Tribute

Eighties motorbikes tests

Honda VF750F Kawasaki GPZ 750 Suzuki GSX 750 ES

The Test of the year

There was atmosphere of racing under the rain in Hockenheim. We had finally managed to gather the three 750 cc. Gold: the Honda VF 750 F, the Suzuki GSX 750 ES and the Kawasaki GPZ 750 on the same day. Grey and low clouds, bursts of cold wind and a steady and heavy rain but I had in my hands the comparative test of the year.

We were going to start the first part of this comparison… the part about performance.  With some bikes, the performance isn’t so important.   Who cares if a Guzzi California or a Harley Davidson Electra Glide goes faster?  However, when in the same winter three brands strive to affirm in the salons that their new 750 cc. bikes are the best sports bikes of all times you have to talk very seriously about performance, stability and maximum power.  Plus, when the three brands are called Honda, Suzuki and Kawasaki you can be sure that none of the three can permit itself the luxury of disappointing.  At these heights, the level of industrial espionage between the three factories is comparable with the operations and counter-operations of the KGB and the CIA.

There are even prototypes that exist in the Experiment Departments of some Japanese factories just to throw their rivals off track.  Each factory has its spies and even double agents, whose job is to make sure that false information arrives at the other factories.  .

A while back, Suzuki and Kawasaki knew (or feared) that Honda was going to start selling a super sport bike version of the 90 Degree V 4 with a motor derived from the NR 500 GP.

With the NR 500, Honda didn’t score a single point during their three years of misfortune, but during those three years of failure, breakage, falls and humiliations, the Honda technicians were perfecting the prototype of a new generation of four stroke motors. The intention of Honda is to make the motor that they used as the base of their initial offensive in high power bikes obsolete… four in line engine. 

Plus, if on the one hand, Honda didn’t make more than a fantastic and beautiful noise with its NR 500 GP, the other Japanese factories knew through their industrial espionage and simple logic or intuition that Honda was preparing to eliminate from its range all its high powered four in line bikes.

Suzuki, Kawasaki and Yamaha also have their 90 degree V four prototypes, but between a prototype and a commercial bike there is an abyss of millions of dollars and years of tests, and besides, a V-4 from Suzuki, Kawasaki or Yamaha would be an imitation in the eyes of the public.

The only brand that can now sell a V-4 without being accused of copying Honda is Ducati, whose V-4 is a reality that roars in the prototype department of Ducati Meccanica.  However, when will it be released into the market and at what price?

It’s clear.  Honda, with the VF 750, has in its hands one of the most promising sports bikes ever sold, and in order not to lost ground against Honda in the prestigious market of super sports bikes, both Suzuki and Kawasaki have decided to launch super sports bikes as well, but with four in line engines that forcibly have to continue in production for some years more.

Yamaha, for its part, decided to attack Honda at their weakest point... the 900 cc displacement, now that the CB 900 Bol D’or already has a few grey hairs. 

The Queen of the shows

During the winter shows, Honda had surprised everyone with its new range of beautiful and exciting models, presenting as its great star the Honda VF 750 F.

On paper there is no doubt. Honda has the advantage. The 90 degree short stroke V-4 with four valves per cylinder and water cooling has captured the imagination of the general public and technicians, too. The narrowness of the engine means that Honda can, in theory, get high speeds without resorting to a powerful engine. We saw last week in the comparison of the Guzzi Le Mans and the Ducati 900 SS that the Ducati with only 70 HP can overcome a Suzuki GSX 1100 ES with 103 HP at maximum speed, thanks to the most logical configuration of the narrow engine. Thus, the Kawasaki and Suzuki technicians received their orders. It is easy for me to imagine the emergency meetings in the prototypes departments. How are we going to defend ourselves against the VF 750 F?

 

The reactions of Suzuki and Kawasaki were different. Suzuki decided to try to get a line of Grand Prix bikes in order to take advantage of the image of their RG 500 from the World championship races.  Sixteen inch wheel in front and a 17 inch one in back, with a thick Michelin Slick and rectangular chassis like the Honda, but only rectangular where it can be seen.  The importance of offering the image of Grand Prix is seen in this “emergency” frame, whose rectangular tubes exist for reasons of esthetics and

Full Floater rear suspension, anti-dive fork, 16 inch wheels, thick read tire, RG colors. To drive the new GSX 750 ES (Euro-Sport) there had to be a noticeable improvement in the power of the GSX 750 four valves per cylinder engine.  In order to be “quick” today, a 750 has to reach 210 km/h. and has to do 400 metros in less than twelve and a half seconds. With 86 HP at 9.000 r.p.m., according to the catalogue figures, the Suzuki GSX 750 ES was presented as a quite sensitive “anti-Honda.”

If at Suzuki they gave great importance to the "image" by trying to give the GSX 750 ES a Grand Prix line to get us thinking of the RG 500, a bike that always left behind the Honda NR 500 V-4 in racing, Kawasaki had no intention of identifying their sports bikes with their KR 500 Grand Prix, since as long as the Honda NR 500 had the justification of being a rolling high technology engine tests bike, the Kawasaki KR 500 competed in the World championships with poor results.                

No; Kawasaki wants to make us forget the KR 500 and the color green. The new Kawasaki sports bikes are red, with the exception of the Lawson Replica, which already is called Replica, and that now comes out in the US painted white instead of green.

To fight again Honda, Kawasaki decided to go back to its same old argument, power and performance.  Through the year, Kawasaki has based its commercial success on bikes so fast that in many years they pushed the limit, becoming considered as “anti-social.”  The old two stroke three cylinder 500 cc was almost a racing bike.  The first Z-900 had much more power than its frame and suspension could take.  

Kawasaki is very conscience of its old image as a manufacturer of fast and unstable bikes, and because of this they wanted to risk having stability problems.  Kawasaki hasn’t had time to experiment with 16 inch wheels on its street bikes and they decided to limit themselves to a new and aggressive sports line with low handlebars and semi-fairing and Uni-track suspension.  However the convincing argument of GPz 750 had to be power. 

Nor were they going to invest at this point in new motors with four valves per cylinder. At Kawasaki the orders to the head of the research department were clear.  More power, higher performance!  We have to beat Honda in performance. 

Kawasaki victory in the performance tests

Friday afternoon, two days before the scheduled performance tests at Hockenheim, we load the Suzuki GSX 750 ES and the Kawasaki GPZ 750 in the Motorrad van to go to the performance test at Bosch on the outskirts of Stuttgart.

And what about the Honda? Long faces among the members of the magazine.   Last minute telephone calls. Some strong words by phone. Problems. Damn it! The test has already been announced in the magazine.   We have the Kawasaki and Suzuki, but the "star" doesn't want to go out on the stage.   Is she afraid?

Don't know exactly what the editor-in-chief of Motorrad said by phone to the director of Honda Germany, but it was sufficiently hard to bring about a small miracle. The problems disappeared and Honda promised to have the VF 750 F ready in time for the Bosch tests. We sent another van to Honda and I left with Reinhard toward Bosch to begin the performance test.

Suzuki declares 86 HP at 9.500 r.p.m., but on the test, and with the motor perfectly tuned, it only measured 79 actual HP. We had to let the engine cool and do it again. I got the agreeable job of being at the controls, crouched over the tank to escape the cold air from cooling turbine.  Reinhard taught me the power curve. Actually the power fell abruptly from 9,500 and there was no advantage from revving the engine. In the second test, the numbers were identical: 79 HP at 9,500 rpm, seven fewer than the 86 of the catalog.

Now the Kawasaki.  According to the catalogue, 87 HP at 9.500.  While the motor was warming up on the tests I knew from the anger of its roar that I was dealing with a bad-ass motor.  It’s curious to do the tests like this with the first contact about performance tests, followed by track tests.  The advantage is that after seeing the power curve drawn out you know exactly at what speed on the track you have to shift to get optimum performance.  If it was difficult to reach 9,500 rpm in the performance tests with the Suzuki, the Kawasaki came through the laps with a breathtaking joy and I decided to shift around 10,000 r.p.m. instead of 9,500.  The power measurements are made in fourth gear, because street tires don’t endure constant speeds in tests at more than 200 kilometers hour. Arriving at 10,000 RPM in fourth in the performance test, the Kawasaki motor didn’t give any sign of being short of breath and I kept the throttle all the way open up to 10,500 rpm.

Fantastic. A motor with a righteous rage. AND... 88 HP at 9,800 rpm and still with useful power to 10,500. Very well... one HP more than the 87 listed in the catalog.

While I was doing a second test on the Kawasaki with identical results, the second van with its precious cargo arrived. The Honda VF 750 F hadn’t failed to keep the appointment, but the carrier told us that when he arrived at Honda they were still tightening the screws on the motor brackets.

We got the Honda at the test, and I started it. However, it didn't want to heat up and was nearly impossible to warm up. It started failing. It stalled, and it didn't want to restart. We lift the tank. We find a grease covered spark plug. And another spark plug this one was also very black. We got four new spark plugs and finally, the engine started to run well, but it’s wheezing and coughing it and took about five minutes to heat up enough to close the choke.

Finally it warmed up, and I could get on and rev it up, pushing the gears up to 10.000 r.p.m. However, after the Kawasaki, the Honda didn’t impress me.  From 2.000 r.p.m., the motor responded in fourth gear, while the Kawasaki didn’t respond until 3.500 r.p.m., but the Honda didn’t rev up with the rage of the Kawasaki.

First test, 83 HP at 9.800 r.p.m. Plus with a power drop at 10.000 r.p.m. The second test came out the same, with 83 HP, seven fewer than the 90 HP of the catalogue.

The HP in the performance tests, however, don’t tell it all. The Ducati 900 SS with 70 HP at 8.400 r.p.m. reached 222 Km/h. and the Guzzi 1.000 (a little wider) with 75 HP had reached the same figure of 222 Km/h.  Despite its advantage in power we saw that the wide Kawasaki would have a disadvantage in aerodynamic penetration and I told Reinhard that perhaps the 83 HP of a V-4 would be capable of beating 88 HP in a straight line.

In the mountains and on the highway... Honda, impressive!

We always do the high tech tests at Bosch on Fridays and the performance test always in Hockenheim on Mondays.  However, the weekends are for breaking in at your leisure on the highway and in the mountains, and during this parenthesis between scientific tests we had the great opportunity of breaking in three 750 under “normal” conditions.

The bike with the sportiest feel is the Suzuki with 16 inch wheels and an aggressive rider position.  Going into curves the Suzuki has a tendency to lean to the inside and this tempts you to straighten up, not to keep the exhausts from scraping the ground, but because the bike invites this kind of driving.  I liked it, but for the other Motorrad testers this feeling of falling to the inside of the bends didn’t convince them.  A tendency to “over-steer”... which gives the bike a very agile and light touch.

There was no wobbling going straight, but with extreme riding the Full- Floater suspension is quite rigid and has a tendency to cause some bouncing in front and in back.  You have to keep it on a short rein and pay attention to the front wheel while riding on roads that are not in good condition. 

Of the three, the one that most invites you to search for its limits is the Suzuki, but the most stable is the Honda.  It rider position is somewhat more erect and the long tank places the rider a little farther back than normal, but the advantage of the Honda over the Suzuki is in its suspension and neutral feel when going into curves. With the Suzuki you can take a series of curves very quickly, but you have to hang on hard to the handlebars and the bike shows some jolts and light wobbling, especially in front.

The Honda holds its course elegantly changing directions without problems and without the rider having to lean too much or force the bike.  The Honda goes where you want.

In a straight line at high speed the Honda goes straight provided that the rider goes into a semi-crouch. Sitting upright at more than 160 kilometers per hour, there is a slight tendency to wobble. But who rides in an upright position at 160 kilometers per hour?

The Suzuki is fun, agile, easy to ride quickly…but the Honda is the safest and the most noble.  It has no equal, confirming the favorable impressions of our first test in Jarama.  Breaking it in on the 1-43 in the Jarama was a pure process and I never had the sensation of being either close to its limits, although it went a little slower on that day, because the bike was an homologation special and accompanied by the mangers of Honda Spain y Honda Belgium.  On the highways of Germany there were no Honda officials making faces, but I didn’t want to be the first to really open up the VF 750 either.  More than anything we had to have the bike in perfect condition for the tests in Hockenheim.  

And the Kawasaki? Well, the Kawasaki had the feel of a 70’s bike. A typical sports bike of earlier times. The 16 inch wheels in front create habits and so do the soft and progressive long-stroke suspension. The Kawasaki, with its hard and Italian suspensions, is so rigid that on a bad highway kit behaves as violently as a Ducati 900 SS, but on a good highway the Kawasaki is noble, very faithful to the trajectories and gives you more confidence.  However, a silly bump in the middle of a curve is enough to cause clunking noises in the suspensions.

If I had tested the Kawasaki before the Honda and the Suzuki, I don’t think I would have found anything wrong with its feel going into curves, but after getting used to the agility and tenderness of the 16 wheel, putting the Kawa in with the 19 wheel was difficult.  The Kawasaki is stable, but its feel is that of a 1.000 cc. from the '70’s, while the Honda and the Suzuki are 750 of the new generation and easier to handle.

Going straight the Kawasaki wobbled at 150 km/h.

The lightest of the three is Suzuki, 238 kilograms with the tank full, while the Honda is the heaviest, 248 kilograms. The Kawasaki, the hardest touch, weighs 241 kilograms.

In general you can say that none of these 750 cc. is light.  In fact, the three 750 cc. weigh as much as the 1.100. The purpose of this return to the 750 cc engine capacity was to reduce weight without sacrificing performance. However, we will have to eliminate many kilograms to allow these 750 cc. bikes to impose on the 1.100, which still offer more power with similar weights.

Kawasaki, the best shifting. Honda spits out the gears

What became clear in sports driving in the mountains was that while the Kawasaki has the best shifting, crisp and short-throw, the Honda suffers from a tendency to spit out.   We all had the same complaint about the Honda.  The gears shift well, but there is an annoying and even dangerous tendency to spit out in some of them, leaving you in a false neutral just when you most need engine braking.  

Another problem with the Honda that makes changing gears and downshifting somewhat delicate is the reduced mass inertia of the crankshaft. The engine loses revs so quickly that you have to downshift quickly (almost kicking it) to avoid problems with the secondary transmission. In the changes from second to first or third to second is too easy to bring rebounds. Honda knows about the problem and this is why they mounted a special clutch to avoid wheel lock.

In Daytona, the bouncing and wheel lock problems with the VF 1100 engines were so severe that the tire wear accelerated rapidly.

 

The general opinion of the testers is that Honda has a quality control problem, since during the last several months different models of Hondas have had the very same gear adjustment problems, problems similar to those that we are currently having with the shifting of the two Yamaha XS 400 bikes that we are testing.

Are there "robots" in Japan with some wires crossed?

Duel on the track

After having fun in the mountains with the test bikes we turned up at the garage of Motorrad at eight o’clock on Monday morning and loaded the three contenders for the title of Super 750 into the van for the trip to Hockenheim and the performance tests.

Rain, rain and more rain.  However, according to Reinhard, the rain is not a problem.  You can go into the curve before the timing zone at 200 kilometers per hour without problems. “No problem as long as you don’t make the slightest steering mistake.“

I love the Germans.  They are people who really look for danger, but always very carefully.  They leave nothing to chance, but push the limits in a mind-blowing way.  There is something really ironic about a country that requires you to pass periodic motorcycle tests and fines you heavily for doing things in traffic that we do in Spain without anyone even noticing, but at the same time has no speed limit on the motorways.  They love controlled danger. 

What Motorrad does in Hockenheim with water is a perfect example of the German character.  I have been racing bikes for fourteen years and sometimes I have had to race on fast circuits with with, but never have I run a maximum speed test on water, even going straight, and much less on a curve at 200 kilometers per hour between straight-aways.

Well, we are going to test these bikes with ice in our veins, as if we were Germans.

Although to put it in plain words, I was afraid, and if they had told me that they had put off the test until the next day, I would not have been angry with them!

The system used was to have two or three testers simultaneously making runs on the test bikes, the reason for this is so that you have "traffic" on the track in both directions.  Reinhard told me, "When you come back to make another run it is better for you to stay to the right."

Since it is very possible to come face to face with another bike going in the opposite direction at about the same speed in the middle of that curve at 200 km/h, I agreed with him that it was a good idea.

Honda-Kawasaki Tie

The Suzuki reached the respectable speed of 210 km/h, which is by no means "chicken shit" but not fast enough to excel in the company of the Kawasaki and the Honda. The Kawasaki, with a stronger initial acceleration, went through the timing zone at 212 km/h. at 214 and 216 km/h., Reinhard was the one who finally reached 216 km/h.

With the Honda there is no feeling of power comparable to that of the Kawasaki, but once it’s in fifth gear, the engine continues to accelerate, and if you do not raise your head or cut your speed going through that curve, the Honda also reaches the 216 km/h. With the Honda, both of us almost reached the same top speed of 216 km/h.

Maybe we put too much importance on speed, but in Germany, where the highways allow pilots to check the real possibilities of their bikes, there is no figure as important as this.  Plus, with two 750 cc bikes, one at 216 km/h. and the other at 210 km/h., we had at our disposal 750 cc motorcycles capable of performances better than a 1000 cc bike of a few years ago.

The other figures that "sell" bikes are those of acceleration. To test acceleration over 400 meters and one kilometer, you need dry asphalt, so we had to return to mount the third wheel and the "computer" once again for timing.

In the US, a difference of a tenth of a second in acceleration over a quarter mile is sufficient to provoke ups and downs in the sale of sport bikes.  A quite illogical thing, because in order to get these figures you have to be a real specialist in drag racing, and to tell the truth, you have to pull wild stunts that have little or nothing to do with civilized driving.

I remember ten years ago when Cycle World published a test of the Norton Commando with a figure of 13.1 in the 400 meters.  The Norton people screamed to high heaven and sent their super-tester, Norman White, on the first flight to Los Angeles, and this one, with a serious look and years and years of experience driving Norton bikes, was able to beat the 13 second barrier,  amazing half of California and forcing Cycle World to change their figures.  All this for 1.5 decimals of a second in the final of the quarter mile.

Motorrad's policy is to make quick starts, but without reaching the extremes of burning out a set of disks in each test.

All three of us made several runs with the test bikes and came out with almost identical numbers. The Kawasaki does the 400m in 12.2 and the 1,000 meters it 23.3, taking a tenth off the Honda in the "quarter mile" and two tenths in the mile. The Suzuki comes in third.

Although the differences in decimals may seem minute to you, they are tangible.  The Kawasaki is the most powerful and with a vengeance, while the Honda, with a less powerful motor, but a narrower power band, is less explosive than the Kawasaki, but quicker than the Suzuki.

Conclusions

HONDA: The best compromise between high sportsmanship and the "all-purpose" bike. It's more neutral cornering, the most elegant.  It has a flat power range, but is able to rev from 2,000 rpm up to a ceiling of 11,000 rpm There is a power cut at 11500 to avoid "savage” riding.  The riding position didn’t please everyone, as some complained about the long tank which forced the rider back.   I don’t dislike the position. If the bike didn't have a weak gear shift and a tendency to lose revs (as a consequence it gets disappointing reactions on secondary transmission) it would be almost an ideal motorbike. The braking is somewhat less than brilliant, almost disappointing at high speed, but of the three, it brakes best.  Honda has "lied" a bit on the maximum power of the 750 F VF obviously for commercial reasons. In the US it is illegal to advertise maximum speed and Honda, whose maximum speed with the VF was really good, has resorted to a misleading figure of 90 hp so as not “to lose points" in the catalog against the 87 hp of Kawasaki (88 hp of which are true) that ran the same as the Honda.

In the US, it is illegal to advertise maximum speed and Honda, whose maximum speed is marked VF, has resorted to the misleading figure of 90 hp in order not to lose points in the catalog against the 87 hp (88 hp of which are true) Kawasaki, that runs like the Honda.

The thing is that Honda is leading the way in the global market of the '80s, and its lead in the 750 engine has little to do with performance.  Honda has the best engine, the most logical setup, because the V 90 engine, especially with the crankshaft positioned across the frame, is an ideal motor that allows optimum aerodynamic penetration and a low center of gravity. With a stroke of only 48.6 mm., the VF 750 F at its maximum speed is only reaching a piston linear velocity of 15.4 m/s, while in the US Championship, Mike Baldwin (and Fast Freddie Spencer at Daytona ) have the green light to rev their VF 750 F engines ready for upto 13,000 rpm (Dr. Taglioni in Ducati Meccanica is working on similar schemes, but with a somewhat longer stroke.)

While Kawasaki GPZ 750 is already spinning at 18.3 meters/second when it reaches its top speed of 216 Km/h., the Honda at 216 Km/h. is just cruising in regards to its mechanical limits, reaching a quiet piston linear speed of 16.3 meters/second. In other words, Honda has just begun to look for HP in its VF 750 F road bike, while in Daytona they have already shown in an impressive way that, for now, no one can follow the VF 750 F with special factory superbikes preparation.

The Honda VF 750 F is the best of the current 750 bikes ... and most troubling for Suzuki and Kawasaki is that the Honda can be easily upgraded.

Kawasaki: Kawasaki's reaction has been successful. Working on the basis of the robust Z 650 Engine, a classic four-cylinder, but without problems and two valves per cylinder, Kawasaki has simply mounted a "competition kit" and has beat Honda in the HP war, beating the VF 750 F in acceleration and matching it in maximum speed.

Plus, as a tip, the classic two-valve per cylinder GPZ 750 is the 750 with the lowest fuel consumption. For the unconditional of sporty driving, the Kawasaki will have a slight advantage even over the Honda, because its engine, powerful, with a punchy power range, is a delight.  Its kick is strong and you must always keep an eye on the revs, because the engine has no ignition cut at high speed like the Honda and is able to rev up the lower gears to 12,000 rpm before valve flotation occurs.

Its change is also the best of the three test bikes, with a good feel and positive action. I didn’t have even one false neutral throughout the test.

However there are also disadvantages in this explosive engine. It’s lacking in the low range. Below 3500 r.p.m. in high gear, the engine simply "does not work". Between 4,500 and 6,000 rpm, however, there is a civilized instantaneous response, whereas above 6,000 rpm the big and violent horses are waiting for us.

If it were a "production" race, the Kawasaki would be perhaps the most stable, because in fast corners and on smooth asphalt it is very elegant and rigid.  However, its hard suspension even set on soft makes the bike difficult to handle on bumpy roads.  It also has a tendency to wobble over 150 Km/h ... while in Hockenheim, at 216 Km / h. it gave me chills when it started wobbling in the front on water.  It has the best braking of the three 750 bikes, but it isn’t exceptional braking.

Entering curves is a little difficult (compared to the Honda and the Suzuki), but its performance is brilliant and the engine is also mounted on the bike silent blocks resulting in less annoying vibrations.

 

Suzuki: It seems ironic that a 210 Km/h. 750 cc. bike capable of accelerations above those of the fastest superbikes from a couple of years ago, has to be criticized for its lack of nerve ... but the thing is that Kawasaki and Honda are tough opponents and Suzuki with a performance that is not insignificant, has remained in the background.

The best of the GSX 750 ES is its speed and position. We all liked his touch from the first kilometers.  It inspires confidence and encourages you to attack.  The bouncing in front and back only occurs on secondary roads because on the circuit and on tarmac it behaves beautifully.

The engine is controlled with a flat curve without any explosive surges like the Kawasaki.

Its fuel consumption is high, although similar to the Honda, but significantly higher than the Kawasaki.

Its braking is weak, apparently due to its hydraulic anti-dive system.

In a series of linked curves the Suzuki, the lightest and most agile, is not the most precise nor the most true to its path, but it requires the least effort when entering a curve and therefore, the least tiring.  It inspires confidence, but it is not at the level of the Kawasaki or the Honda in performance.

General Conclusions

We are still far from the ideal 100 HP, 200 kilo sports bike, but this utopia no longer seems impossible.  The new 750 cc bikes are getting close to 90 HP and now the only thing left to do is cut their weight. 

At the moment, however, the 1.100 bikes continue to offer a very favorable weight power ratio.  There’s a little bit of dishonesty with these bikes.   They promise a little more than they give.  Honda, with its aluminum colored iron frame, and Suzuki, with its frame that is only tubular in visible places, don’t wan to trick us, but the results are so positive that we forgive them.

And instead of being a test of exotic motorcycles banned from the European market, it seems that two of these bikes, the VF 750 F and Suzuki GSX 750 ES, will be on sale in Spain this year.

I do not think that the displacement of the 750 cc engine is ideal, because the most important thing is the weight in relation to power, and the engine in itself. Maybe tomorrow Japanese brands will make 800 cc or 850 cc displacements popular, or perhaps return once again to the large displacements. For now, however, the 750 are back in fashion, and the bike to beat, for now, is the VF 750 F, and beat without a V-4 is going to be difficult ... if not impossible.