Yamaha Vmax

The Vmax is a drag-bike type motorcycle from the Japanese manufacturer Yamaha , which was introduced in 1984. The large-volume, high-torque four-cylinder - V-type engine with 107 kW (145 hp ) allowed a series motorcycle with high acceleration . During its long construction period, it experienced only minor changes and remained largely without competition in its market niche. In 2008 a completely newly developed successor version was brought onto the market. It now has a displacement of 1679 cc and develops 147 kW (200 hp).

V-boost

The Vmax uses the “V-Boost-System” to increase performance, which is technically only feasible for V-engines. The four downdraft carburettors each supply a cylinder via separate intake ducts. The channels for cylinders 1 and 2 and for cylinders 3 and 4, which are arranged in pairs, are each provided with an additional throttle valve, which is controlled by a speed-dependent servomotor. The servomotor opens the throttle valve at approx. 6,500 min ^{−1 in} order to release the largest cross section at 8,000 min ⁻¹ . As soon as the flaps are opened, each cylinder is supplied by two carburettors during the intake stroke, which increases the filling in the cylinders. This means on the other hand below 6,500 min ^-1 more torque due to lower intake cross section in the carburetors.

VMX1200 Vmax (2LT)

Yamaha
Yamaha Vmax (VMX1200)
Yamaha VMX1200 Vmax (2LT)
Manufacturer	Yamaha Motor Corp.
Production period	1985 to 2006
class	motorcycle
design type	Naked bike
Motor data
Liquid-cooled V4 four-stroke engine, 70 ° bank angle , DOHC, 4 valves per cylinder
Displacement (cm³)	1,198 cc
Power (kW / PS )	106.6 kW (145 hp) at 8,700 min ^-1
Torque ( N m )	122 Nm at 7500 min ^-1

transmission	5-speed manual transmission
drive	Cardan drive
Brakes	front: double disc, Ø 298 mm, 4-piston fixed calipers, rear: disc brake, Ø 298, 1-piston floating caliper
Wheelbase (mm)	1,590 mm
Seat height (cm)	780 mm
Empty weight (kg)	262 kg (dry)

Akira Araki, project manager at Yamaha, was on a market research tour in the USA in the early 1980s . The "Bridge Races" were an impressive experience for him. Two motorcycles lined up at the start line and tried to get over the quarter mile distance (402.34 m) as quickly as possible using a bridge over the Mississippi River . Yamaha later called these races "Zero-4-Race". His first thought was to build a motorcycle that was "strong on the straights and really fast". With these impressions, Akira Araki returned to GKDI, an external Yamaha design company in Santa Monica , California . He, Kaoru Ashihara (engine development) and the design team, consisting of the Japanese Kurachi and the English John Reed , worked for almost a whole month to put the concept on paper. Ed Burke , Senior Product Planner at Yamaha USA, supported the team in their work. After intensive consideration, a 1: 1 model was created. When they had completed this, they returned to Japan to present the study internally. The search for a suitable engine turned out to be difficult at first, but since a V4 engine was just being developed for the tourer Yamaha XVZ 12/13 Venture , which offered great potential, they resorted to it. It was a problem, however, to bring the rather moderate engine with its 66 kW (90 PS) to the targeted 140 to 150 PS. A turbocharger was discarded due to lack of space - after revising the compression, inlet and outlet ducts, the “V-Boost System” was developed. Another problem was to get the chassis so stable that it could withstand the brute engine power and torque at the time . A cardan drive was used instead of a drive chain . Because of the limited space due to the large engine, z. B. the 15-liter fuel tank under the seat.

The Vmax premiered at the US dealer meeting in Las Vegas in October 1984. The machine was scheduled for the 1985 season and should first be launched in the USA. The naked bike was with a time of under 11 seconds on the quarter mile the fastest accelerating production motorcycle with an engine power that nearly Prix machines zoom handed to the former Grand. After further presentation in Japan and Europe , the Vmax was highly praised in the media around the world and sold very well in 1985 and 1986 - although it was only built for a manageable target group, not least because of the comparatively high price.

Jean Claude Olivier , Director of Yamaha France , urged Vmax to be approved in Europe. For the engineers at Yamaha, it was a challenge to prepare the chassis for the high-speed requirements in Europe. In 1986 the Vmax was first presented in France. The European version did not initially have a V-Boost system and therefore the engine output was limited to 98 HP in order to meet the stricter European approval criteria of the time. In the late 1990s, more Vmaxs were sold in France than in the US. Yamaha USA soon asked for a smaller Vmax version, e.g. B. with 750 cm³. The project was soon abandoned for structural reasons, but with the 45 ° forward inclined inline four-cylinder engine of the FZ750 , an American model, the FZX750 , was built from 1985 , which was sold in Europe under the model name Fazer . The Vmax has remained without significant competition, Kawasaki tried it in 1986 with the ZL1000 Eliminator and Honda with the X4 presented in 1997 , which was mainly sold in Japan. In 2005, Yamaha launched a special model for the 20th anniversary. The production of the first generation Vmax was not stopped until 2006, until then the motorcycle was built and sold by Star Motorcycles , a subsidiary of Yamaha in the USA.

Technical specifications

engine

Lubrication system: wet sump lubrication
Mixture preparation: 4 flat slide carburetors Mikuni BDS35 with "V-Boost function", electric fuel pump
Acceleration: 3.2 sec to 100 km / h

Power transmission

Clutch: multi-disc clutch in an oil bath
5-speed gearbox with cardan shaft

Model variants

Over the years a number of Vmax models have been built for export. In addition to the models listed below, there was also a special “Black Max” model. Here the exhaust system, intake funnel, rims and fork tubes, as well as some applications on the engine were painted black or anodized. The Black Max is particularly often available in the rather unpopular 98 hp version. For collectors and for a later increase in value, it therefore plays a rather subordinate role despite the special appearance.

model	Construction period	For export country	Power hp	Torque	Others
1FK	1985	United States	145	124	with V-Boost, 34 mm carburetor , Miles speedometer
1JH	1985	USA (California)	145	124	Emission control, modified carburetors and camshafts
1GR	1985-1986	Canada	145	124	with V-Boost, 35 mm carburetor, km / h speedometer
1UT	1986	United States	145	124	otherwise like 1FK
1UR	1986	USA (California)	143	120	otherwise like 1JH
2EN	1987-1990	Europe	122	102	Without V-Boost with km / h speedometer and light switch, 35 mm carburetor, max. Speed 8500 / min, other final ratio
2WE	1987-1990	United States	145	124	35 mm carburetor, changed wiring diagram, otherwise like 1UT
2WF	1987-1990	USA (California)	140	120	35 mm carburetor, changed wiring diagram, otherwise like 1JH
2LT	1987-1992	Canada	145	124	35 mm carburettor, changed wiring diagram, 1991 ignition system, otherwise like 1GR
2WE	1991-1992	United States	140	120	Other camshafts, ignition system, exhaust
2WF	1991-1992	USA (California)	136	118	Other camshafts, ignition system, exhaust
2EN	1991-1992	Europe	120	100	Different ignition system, exhaust
2WE	1993-1995	United States	140	120	Changed fork and brake
2WF	1993-1995	USA (California)	136	118	Changed fork and brake
2LT	1993-1995	Canada	140	120	Changed fork, brake and exhaust
2EN	1993-1995	Europe	120	100	Changed fork and brake
2WE	1996-2001	United States	136	118	Modified oil filter, final drive, gearbox, clutch
2WF	1996-2001	USA (California)	136	118	Modified oil filter, final drive, gearbox, clutch
2LT	1996-2001	Canada, Germany	140 (98)	120 (100)	Modified oil filter, final drive, gearbox, clutch
2EN	1996-2001	Europe, 96/97 Germany	120 (98)	100	Modified oil filter, final drive, gearbox, clutch
3UF	1990-1992	Japan	140	120	Speed cutter 190 km / h
3UF	1993-1995	Japan	136	118	Different fork, brake, exhaust
3UF	1996-2001	Japan	136	118	Modified oil filter, final drive, gearbox, clutch

Strengths and weaknesses

Its critics often pointed out the weaknesses, especially the chassis. The Vmax tends to oscillate at higher speeds due to the high cross-section of the rear diagonal tire and the very rear-heavy series design . Contrary to some “expert opinions”, the frame is, however, sufficiently rigid and not one of the weak points. This must only be stiffened with gusset plates in the event of extreme increases in performance. The sometimes not very precise production of the bearing shells and the track offset are also responsible for the high-speed commuting. Mainly, however, the outdated diagonal tires and the rear-heavy design are responsible. This promotes a high level of lift on the front wheel at high speeds and strong oscillation can occur. At this point, the manufacturing tolerances of the bearing seats etc. come into play again. The worse these are, the earlier the commuting occurs. But just switching to modern rims with radial tires means that the pendulum disappears 90%. Please note, however, that a maximum of 180 mm wide tires (usually dimension 180/55 ZR 17) fits into the standard swing arm. With wider tires, the swing arm must be welded around or replaced. However, taking into account the engine power, a 180 definitely represents the best compromise between optics, handling and traction.

Above all, the early years of construction show insufficiently dimensioned brakes.

The chassis design with a flat steering head angle, large caster and long wheelbase as well as the comparatively high curb weight allow the Vmax in tight combinations of curves, e.g. B. move cumbersome for the driver on mountain roads. On normal country roads, however, their cornering performance is not significantly worse than on motorcycles such as. B. an XJR1300 . Only the standard low lean angle significantly limits the fun in curves. The Vmax was not designed for tight turns or racing.

The engine with its typical sound, the enormous acceleration and the pulling power were always praised. The Vmax is one of the few motorcycles that shows an almost linear curve of torque and power from idle to maximum speed.

Tuning

Due to the inadequacy of the chassis, as well as optical reasons, the Vmax was the subject of numerous conversions early on. Nowadays it is therefore almost more difficult to get an original Vmax on the used market than a converted one. The conversions are primarily aimed at the drivability of the Vmax. A conversion to a 17-inch rim (from Georg Deget Motorradtechnik) including radial tires results in better handling and more stable road holding at higher speeds. The track offset, which is disadvantageous in terms of driving dynamics, is also largely eliminated. Chassis improvement: Upside-down fork for greater torsional rigidity and a little more weight at the front (standard lift at the front is one of the main weak points), longer struts at the rear (maximum 5 cm, otherwise the articulation angle of the cardan universal joint is too large), exhaust system against a lighter one swap (only the standard rear collector is very heavy and thus ensures a rear-heavy design), higher footrest system. With the latter, however, it should be noted that it should be sufficiently massive because the original pillion footrest plate on the left acts as a frame connection in the area of the tank. The "tuning" of the 98 hp version to the open power of 136 hp is almost impossible because it is simply too expensive. The European version is not throttled, which can be reversed, but the V-Boost system, which is mainly responsible for the performance, has been completely omitted, which makes this model a simple naturally aspirated carburettor. In addition to the pure hardware (boost system, servomotors, trains ...) there is also the wiring harness and the CDI. These parts are only offered at a very high price, even used. All the necessary parts now cost around 4,500 marks.

Vmax (RP21, from 2008)

Yamaha
Yamaha Vmax, model year 2009
Yamaha Vmax (RP21)
Manufacturer	Yamaha Motor Corp.
Production period	since 2008
class	motorcycle
design type	Naked bike
Motor data
Liquid-cooled four-cylinder four-stroke V-engine, 65 ° cylinder angle, DOHC, 4 valves per cylinder, electronic fuel injection, 12-hole injection nozzles
Displacement (cm³)	1,679
Power (kW / PS )	147/200 at 9000 rpm.
Torque ( N m )	167 at 6500 rpm.

transmission	5-speed manual transmission
drive	Cardan drive
Brakes	front: double disc, Ø 320 mm, 6-piston fixed calipers, rear: disc brake, Ø 298, 1-piston floating caliper, ABS
Wheelbase (mm)	1700
Seat height (cm)	77.5
Empty weight (kg)	278 (dry)
Previous model	Yamaha VMX 1200 Vmax (model 2LT)

At the 39th Tokyo Motor Show in 2005, a Vmax successor was presented as a concept motorcycle. The new Vmax RP21 model based on this has been manufactured by Yamaha since 2008 and sold worldwide. The model name only bears the name "VMAX" without any further abbreviations that refer to the displacement, for example. Like the 2005 design study, the design is based on the first model, but technically it has been completely redeveloped.

The machine has a nominally 200 HP (147 kW) V4 engine with a cylinder angle of 65 ° instead of the previous 70 °, the two intake camshafts driven by timing chains drive the two exhaust camshafts via spur gears. The mixture prepares an electronic gasoline injection, as an adequate replacement for the "V-Boost-System" of the first Vmax generation, Yamaha uses the "YCC-I", an electronic intake control, in which the upper of the two intake funnel batteries are attached 6,650 min ⁻¹ can be raised a little in order to achieve a higher peak performance through a shorter suction path. The electronic throttle valve control "YCC-T" is also used in the Vmax. The characteristic side air scoops are made of aluminum and supply the airbox with fresh air.

The gearbox still has five gears, but the multi-plate oil bath clutch now has an anti-hopping function . As with the original model, the secondary drive is via a cardan shaft .

The chassis no longer consists of a classic steel double loop frame, but of an aluminum bridge frame with the engine as the load-bearing element. The telescopic fork and the shock absorber can be adjusted in terms of the spring base and damping. Yamaha uses 18 inch rims, which are rather unusual these days , probably for optical reasons. The first tires (model BT 028, special code G) had to be developed by Bridgestone especially for the Vmax. The disc brakes are combined with 6-piston fixed calipers at the front , and the motorcycle has an anti-lock braking system (ABS) for the first time in model history .

Initial tests in the trade press reported slight unrest in the chassis, which manifested itself in pendulum movements when driving long curves at high speed. This may be the reason why the top speed is electronically limited to 220 km / h. The engine only achieves its maximum output in 4th gear, in the other gears the engine management system reduces the power output. According to Yamaha, however, thanks to special programming of the control unit, it is possible to accelerate the classic ¼ mile from standstill with full power.

Sales, initially limited to 1500 units in Europe, began in November 2008 at a price of € 19,750. Since the 2010 model year it has been available for € 22,995. The motorcycle can only be ordered through the official Yamaha Vmax website. Previous test drives for interested parties are not yet planned, but it is now possible to rent a Vmax for a fee from selected dealers.

Web links

Commons : Yamaha VMax - collection of pictures, videos and audio files

Official Vmax product page on yamaha-motor.de ( Memento from August 8, 2012 in the Internet Archive )
Extensive article about the Vmax in the Yamaha Design Cafe

Individual evidence

↑ Georg Deget motorcycle technology rim extension and swing arm conversion. In: Georg Deget Motorradtechnik, rim widening and swing arm conversion. Retrieved on May 29, 2019 (German).
↑ Georg Deget Motorradtechnik Rim widening and swing arm conversions by a specialist. Retrieved on May 29, 2019 (German).
↑ https://www.youtube.com/watch?NR=1&v=pSonecPgtuQ
↑ The legend lives on ( Memento from November 4, 2011 in the Internet Archive )
↑ VMAX rental ( Memento from November 3, 2011 in the Internet Archive )

[1] Georg Deget motorcycle technology rim extension and swing arm conversion. In: Georg Deget Motorradtechnik, rim widening and swing arm conversion. Retrieved on May 29, 2019 (German).

[2] Georg Deget Motorradtechnik Rim widening and swing arm conversions by a specialist. Retrieved on May 29, 2019 (German).

[3] ttps://www.youtube.com/watch?NR=1&v=pSonecPgtuQ

[4] The legend lives on ( Memento from November 4, 2011 in the Internet Archive )

[5] VMAX rental ( Memento from November 3, 2011 in the Internet Archive )