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Информация по мотоциклу Bimota 500 V Due

Bimota V Due — последний двухтактный 500cc GP-байк

Оказывается, V Due – единственная модель мотоцикла от Bimota, которая оснащалась двигателем собственного производства. На всех остальных моделях вы обнаружите либо чужие, либо совместные разработки с другими компаниями.

Запущенные в 1997 году производство 2-х тактные 500-кубовые мотоциклы V Due с водяным охлаждением имели отличные показатели:
— двухтактный двигатель инжектор, V-twin
— мощность 110 л.с @ 9000 об/мин.
— крутящий момент 90 Нм @ 8000 об/мин
Кроме того, вместо обычного карбюратора, компания Bimota применила свою технологию прямого впрыска, на разработку которой ушло около 8-ми лет. Прямой впрыск от Bimota обещал снизить загрязнения для достижения соответствующих Европейских и Американских стандартов.

Но отличные показатели в плане экологии и экономности – в данном случае не были приоритетными для Bimota.

V Due был призван стать гоночным GP байком в классе 500cc, что означало необычайно жаркий нрав мотоцикла, сниженный вес благодаря легкой алюминиевой раме, специальной подвеской, 6-скоростной коробкой передач кассетного типа. Сюда можно добавить 17-дюймовые колеса, полностью настраиваемые 46мм вилку от Piaoli, передний амортизатор Ohlins, тормоза от Brembo и шины 120/70 ZR17 спереди, и 180/55 ZR17 сзади.

Благодаря некоторым доработкам V Due в выхлопной системе и обтекателях удалось достигнуть минимального веса в 150 кг. По данным некоторых журналов конца 90-х годов, этот мотоцикл был способен пройти четверть мили (400 метров) за 12,5 секунды, достигая за это время скорости 185 км/ч. А максимальной скоростью для него было 265 км/ч.

Тем не менее, этот экзотичный, дорогой (около 30 000 долларов) и желанный мотоцикл получил двигатель, который не был полностью совершенным. Сама Bimota признала, что не смогла воспользоваться всем потенциалом его инжектора и двух тактов.

В итоге, опустив руки, Bimota остановила производство V Due на количестве 340 шт. хотя предполагала выпустить 500, после чего собиралась показать мото-сообществу доведенную модель V Due Evoluzione Strada. Но, к сожалению, к тому моменту (это был примерно 2000 год) компания прекратила свое существование и была признана банкротом не получив шанса продать эти ре-инженированные мотоциклы.

Позже, все непроданные мотоциклы V Due были скуплены неким Пьеро Каролини (Piero Caronni). Поэтому, если вы являетесь коллекционером мотоциклов, вам определенно следует обратиться к мистеру Каролини и поставить к себе в гараж среди других раритетов новенький непользованый Bimota V Due.

  • Назад
  • Вперёд

The story of my Bimota V-Due

Bimota always borrowed someone else’s engine, put it in their own design and ended up with something special. A few years ago they wanted to build a GP replica bike and decided on something quite spectacular. A GP replica powered by their own 500 cc two stroke fuel injected engine. The result was, on the face of it, purely spectacular. It weighed the same as an Aprilia RS250 but with twice the power and looked the business. The downside was that it didn’t work, literally. Owners complained about everything from peaky performance to intermittent power, dodgy electrics, plug fouling, weak cranks etc. The owners demanded a full refund. Bimota obliged and subsequently went bankrupt.

The V due engineer (Piero Caronni) for Bimota ended up buying all of the bikes, spares and legal rights and set up on his own. Many bikes were given the full overhaul to fix including binning the direct fuel injection system in place of a set of Dellorto carbs. This worked to a certain extent and can still be bought today. Good results have been obtained with retaining the direct injection system and upgrading the rest of the internals. The injection bikes are of course more in keeping with the original idea from Bimota and carbs were a quick fix with limited success.

Bearing all of the above in mind I am a true two-stroke nut and wanted one from day one. The downsides are as follows:

  • You buy it blind from a stranger in Italy who speaks little English.
  • You have to choose from an original bike with no modifications, a carburetor bike or an injection bike with some problems fixed.
  • They cost the earth and they come with no warranty.
  • You cant ride one in your local dealership to see what it rides or fits like.
  • The factory in Italy openly admit the bikes are fraught with problems.
  • They are unreliable and spares are a costly nightmare.
  • On full power they only do 15 miles to the gallon they drink fully synthetic two stroke oil at Ј15.00 a litre like its going out of fashion.
  • It is subject to 17.5% VAT duty at the point of registration in the UK.
  • It has to be put through the UK SVA test which it may or may not pass and it has to be road registered at DVLA and may go on a P plate as bike made in 1997.
  • The delivery man speaks even less English.
  • Belly pan cracks after several miles of riding.
  • Engine needs total strip and rebuild by a two- stroke expert prior to ever riding due to set up at factory being very poor, then it needs full rebuilds approximately every 3K miles.
  • It may never arrive.
  • It may never run.

The good points speak for themselves though:

  • It is a 500CC two stroke that looks the business and weighs very little.
  • If you have always wanted a big two stroke your options are limited. Its either buy a 350 LC and tune it to the max, buy an RGV 250 or Aprilia rs 250 type machine and bore the engine out, buy an RD or RG 500 and ride it as is or update the bike overall or start a 500cc special project like an RGV 500.
  • If you want a modern 500cc two stroke with modern extras, modern handling and looks there is only the V-Due.
  • There are only a handful in the UK and most are track day bikes only. The remaining bikes are unlikely to meet in the same place at the same time- although that would be a sight.

I saw one advertised years ago and I wanted it, but couldn’t afford it. I read they were unreliable, owners sent them back and they were bankrupt, I was gutted. I read that someone had bought the rights to them and was selling them off. They were still too expensive though.

I bought an RD350 instead and rode it till it blew. I bought an Aprilia RS250 and loved it so much I bought another. I owned everything from a Fireblade to a Ducati 851 to a GSXR 1100. and everything in between. I still wanted a V Due, but couldn’t afford one.

I looked at building a 500 cc special via BDK racing, who specialize in RGV 250/500 conversions, but built up bikes were circa Ј6000 plus. I also looked at buying an RG or RD 500 and updating it. But it was too expensive given the poor quality finish and unreliability. So I decided to buy a V Due.

I looked for a V-Due carb version and found the only one in the country (already road registered) was for sale. Whilst negotiating around the Ј10K marker it was sold to someone else. Gutted, I contacted the factory in Italy directly and swapped lots of emails.

In the end I decided on an injected bike with electrics, lubrication and crank problems solved. Only issue with the bike is that it oils up the plugs constantly causing poor jerky running, intermittent power delivery and plugs need replacing after every trip. Great.

I agreed a price in Euros with factory. Deposit wired to his account in Italy. Delivered via Belgium in a van to bike dealer in Norfolk. Euros sent by post to pay the balance. Delivered to me at home a month later.

Luckily for me I had a very good rapport with an owner called Paul Clarke from London who steered me in the right direction with regards to problems encountered.
I put the bike through SVA test in the UK and it passed first time- although it wasn’t running.

It ran like a pig, then overheated , then stopped. So I sent to a man in the know — 2 stroke god Mark Brown from Nottingham, to be adapted to have oil injectors moved to the throttle bodies to run like a normal two stroke. Mark Brown completely sorted the bike from top to bottom. I also had the water cooling system adapted to stop it over heating, changed the ECU units as faulty ones came with bike, swapped the fuel pump as it was gunged up and not working correctly and put 3 different speedos on it until I found one that worked.

I’ve never looked back since. best bike in the world. Hassle factor 10 out of 10, Enjoyment/pose factor 1 million. What a treat.

In 1996-97, Bimota was set to introduce a new machine that would revolutionize sport bikes. It would be an unstoppable, razor sharp 500cc two-stroke that would give 1000cc four strokes a run for their money, in a time when it appeared that two-strokes were on their way to the bone yard. There was a lot of excitement brewing around the forthcoming V-Due (literally, V-twin) — not only because of the mouth-watering specs and the fact it was being built by one of motor cycling’s most legendary boutique marques, but also because it promised to fix the «problem» that two stroke road bikes were facing.

Читать еще:  Мотоцикл Skycruiser 125 (2009): технические характеристики, фото, видео

That «problem» was increasingly strict emissions laws. In the 1990s strokers were getting phased out, quickly, due to stricter EU and EPA emissions requirements. They were being relegated to off-road and track use — as either motocross machines or track-only race bikes, with street legal bikes an impossibility in the US and Europe in the face of the new restrictions. Two strokes, by their very design, are nasty polluters. Not only because of the mix of oil and fuel required to lubricate the bottom end, but also by the nature of a two-stroke cycle.

You might want to skip over this next bit if you get bored to death by technical theory.

A two-stroke operates by simplifying the usual four stroke cycle. Four strokes are «suck-squish-bang-blow» — intake charge of air and fuel on down stroke, compression stroke up, ignition and push of piston back down, exhaust stroke up to expel gasses. Valves in the top of the combustion chamber open to let the fuel/air in, close to allow compression and ignition, then open again to let the exhaust gas leave. Repeat. Two strokes have two cycles — suck/blow-squish/bang. The «valves» are open ports in the walls of the cylinder, routed through the crankcase. When the piston goes down, it pulls fuel mix in on one side of the chamber while simultaneously forcing exhaust gas out the other side. When it goes up, the chamber is sealed, compression is made, ignition, piston goes back down. Repeat.

The advantage of strokers is far more power per displacement than a four stroke of equivalent displacement. Sometimes double — a 500cc two stroke is roughly equivalent to a 1000cc four stroke. But in a much lighter and simpler package. Hence why the V-Due was so hotly anticipated — here was a lightweight super sport with top shelf components that could eat bigger sport bikes for breakfast. It was hyped up to be the closest thing to a road legal GP bike since the RG500 and NS400R bowed out in 1987. In fact, it was touted as a legitimate GP bike for the road — the original V-Due was a racing project that was later switched to a road bike program. Power was expected to be 110hp in a bike that weighed just over 300lbs — remarkable numbers for the mid 90s, when a typical super bike was easily 450-500 lbs.

The disadvantage of ‘strokers is short service life (frequent bottom end rebuilds) and terrible emissions. Up to this point two strokes used carburetors — a carburetor will flow fuel constantly, even when the throttle is closed, because it delivers fuel based on the vacuum of the intake. The most strictly controlled emissions are usually unburned hydrocarbons (unburned gas) making its way into the exhaust. It’s a problem on four strokes as well. Two strokes are especially bad because the exhaust and intake ports are open at the same time — so raw fuel mix will always flow across and get into the exhaust no matter how carefully you tune the engine.

Still awake? Good, back to the Bimota.

Why was the V-Due the only game in town, and why was it so anticipated? Because Bimota claimed they had fixed the emissions issue by developing a fuel injected two-stroke with electronic ignition, something that had never been done in a motorcycle before. Direct fuel injection delivers a jet of gas when needed into the cylinder, and shuts off completely when it isn’t — unlike a carburetor. You can time fuel delivery precisely so it won’t slip through the combustion chamber and into the exhaust, and the electronic ignition can time the spark to ensure a full burn. The V-Due also used forced lubrication for the bottom end, with only minor oil mixing required to lubricate the pistons. It was topped off with a trick cassette gearbox and dry clutch, racy stuff for a road bike. So, some revolutionary technology and clever engineering and the two-stroke lives to fight another day. All eyes were on Bimota, and some early press reviews praised the handling and power the V-Due was going to offer.

With this kind of hype, disappointment was inevitable. And boy, was the V-Due a disappointment when it hit the market.

The first production models arrived in 1997 and right away major problems became apparent. Yes, they passed emissions testing and the bike was 50 state legal — but the fuel injection system was not at all sorted out, and the bikes were almost completely un-rideable. Throttle response was terrible, the engine hunted badly at steady speeds, and power delivery was extremely violent and only came on at the top of the rev range. While it was light and quick, power wasn’t up to snuff among the crop of high powered super bikes that began to emerge in the late 90s. Aside from being despicable to ride it also had electrical faults, a tendency to foul spark plugs, and had some major mechanical faults that led to piston and crank seizures. Oh, did I mention that this half-baked Italian cost about $30 000 (Ј14500)? Yeah, that definitely did not help the reputation — especially among UK magazines where writers have a penchant for being brutal in their reviews when something doesn’t measure up.

It wasn’t all bad. While the in-house engine design (built by Moto-Morini) was more or less a turkey, the chassis was brilliant. It looked sexy and had stellar handling, helped by a dry weight right around 320 lbs. Front suspension was courtesy of Paoli, rear by Ohlins. Brembo Goldlines took care of stopping power. Carbon fibre was used liberally. It looked the business and could find its way around a track, even if it didn’t run properly. Like many Italian motorcycle fans have said since time immemorial — it’s brilliant, when it’s working.

It quickly became clear that the V-Due was a liability for Bimota. They began accepting returns and in 1998 they release the Evoluzione upgrade — which ditched the wonky fuel injection for a pair of 39mm Dellorto carburetors. Suddenly the modus operandi of the V-Due (introducing modern FI to two strokes) was ditched in an effort to simply make the thing work. But it was a case of too little, too late. Bimota went bankrupt in 1999, after having produced 340 V-Dues of the proposed 500 example run, 21 of which were the Evoluzione.

But all was not lost. One of the project engineers, Piero Caronni, bought the remaining bikes and spares when the company went into receivership. He subsequently began modifying and fixing the issues, culminating in the Evoluzione 03, Evoluzione 04 and Edizione Finale models — introduced in 2003 and 2004. All used carburetors and modified engines with much improved reliability. Power was up as well, to 120 hp for the 03 and 130hp for the 04 and Finale. These sorted bikes have a strong cult following, with dedicated owners who are quick to dismiss the bad reputation surrounding these machines.

The story of my Bimota V-Due

Bimota always borrowed someone else’s engine, put it in their own design and ended up with something special. A few years ago they wanted to build a GP replica bike and decided on something quite spectacular. A GP replica powered by their own 500 cc two stroke fuel injected engine. The result was, on the face of it, purely spectacular. It weighed the same as an Aprilia RS250 but with twice the power and looked the business. The downside was that it didn’t work, literally. Owners complained about everything from peaky performance to intermittent power, dodgy electrics, plug fouling, weak cranks etc. The owners demanded a full refund. Bimota obliged and subsequently went bankrupt.

The V due engineer (Piero Caronni) for Bimota ended up buying all of the bikes, spares and legal rights and set up on his own. Many bikes were given the full overhaul to fix including binning the direct fuel injection system in place of a set of Dellorto carbs. This worked to a certain extent and can still be bought today. Good results have been obtained with retaining the direct injection system and upgrading the rest of the internals. The injection bikes are of course more in keeping with the original idea from Bimota and carbs were a quick fix with limited success.

Bearing all of the above in mind I am a true two-stroke nut and wanted one from day one. The downsides are as follows:

  • You buy it blind from a stranger in Italy who speaks little English.
  • You have to choose from an original bike with no modifications, a carburetor bike or an injection bike with some problems fixed.
  • They cost the earth and they come with no warranty.
  • You cant ride one in your local dealership to see what it rides or fits like.
  • The factory in Italy openly admit the bikes are fraught with problems.
  • They are unreliable and spares are a costly nightmare.
  • On full power they only do 15 miles to the gallon they drink fully synthetic two stroke oil at Ј15.00 a litre like its going out of fashion.
  • It is subject to 17.5% VAT duty at the point of registration in the UK.
  • It has to be put through the UK SVA test which it may or may not pass and it has to be road registered at DVLA and may go on a P plate as bike made in 1997.
  • The delivery man speaks even less English.
  • Belly pan cracks after several miles of riding.
  • Engine needs total strip and rebuild by a two- stroke expert prior to ever riding due to set up at factory being very poor, then it needs full rebuilds approximately every 3K miles.
  • It may never arrive.
  • It may never run.
Читать еще:  Мотоцикл Platina 125 Dumdar Sawari (2011): технические характеристики, фото, видео

The good points speak for themselves though:

  • It is a 500CC two stroke that looks the business and weighs very little.
  • If you have always wanted a big two stroke your options are limited. Its either buy a 350 LC and tune it to the max, buy an RGV 250 or Aprilia rs 250 type machine and bore the engine out, buy an RD or RG 500 and ride it as is or update the bike overall or start a 500cc special project like an RGV 500.
  • If you want a modern 500cc two stroke with modern extras, modern handling and looks there is only the V-Due.
  • There are only a handful in the UK and most are track day bikes only. The remaining bikes are unlikely to meet in the same place at the same time- although that would be a sight.

I saw one advertised years ago and I wanted it, but couldn’t afford it. I read they were unreliable, owners sent them back and they were bankrupt, I was gutted. I read that someone had bought the rights to them and was selling them off. They were still too expensive though.

I bought an RD350 instead and rode it till it blew. I bought an Aprilia RS250 and loved it so much I bought another. I owned everything from a Fireblade to a Ducati 851 to a GSXR 1100. and everything in between. I still wanted a V Due, but couldn’t afford one.

I looked at building a 500 cc special via BDK racing, who specialize in RGV 250/500 conversions, but built up bikes were circa Ј6000 plus. I also looked at buying an RG or RD 500 and updating it. But it was too expensive given the poor quality finish and unreliability. So I decided to buy a V Due.

I looked for a V-Due carb version and found the only one in the country (already road registered) was for sale. Whilst negotiating around the Ј10K marker it was sold to someone else. Gutted, I contacted the factory in Italy directly and swapped lots of emails.

In the end I decided on an injected bike with electrics, lubrication and crank problems solved. Only issue with the bike is that it oils up the plugs constantly causing poor jerky running, intermittent power delivery and plugs need replacing after every trip. Great.

I agreed a price in Euros with factory. Deposit wired to his account in Italy. Delivered via Belgium in a van to bike dealer in Norfolk. Euros sent by post to pay the balance. Delivered to me at home a month later.

Luckily for me I had a very good rapport with an owner called Paul Clarke from London who steered me in the right direction with regards to problems encountered.
I put the bike through SVA test in the UK and it passed first time- although it wasn’t running.

It ran like a pig, then overheated , then stopped. So I sent to a man in the know — 2 stroke god Mark Brown from Nottingham, to be adapted to have oil injectors moved to the throttle bodies to run like a normal two stroke. Mark Brown completely sorted the bike from top to bottom. I also had the water cooling system adapted to stop it over heating, changed the ECU units as faulty ones came with bike, swapped the fuel pump as it was gunged up and not working correctly and put 3 different speedos on it until I found one that worked.

I’ve never looked back since. best bike in the world. Hassle factor 10 out of 10, Enjoyment/pose factor 1 million. What a treat.

In 1996-97, Bimota was set to introduce a new machine that would revolutionize sport bikes. It would be an unstoppable, razor sharp 500cc two-stroke that would give 1000cc four strokes a run for their money, in a time when it appeared that two-strokes were on their way to the bone yard. There was a lot of excitement brewing around the forthcoming V-Due (literally, V-twin) — not only because of the mouth-watering specs and the fact it was being built by one of motor cycling’s most legendary boutique marques, but also because it promised to fix the «problem» that two stroke road bikes were facing.

That «problem» was increasingly strict emissions laws. In the 1990s strokers were getting phased out, quickly, due to stricter EU and EPA emissions requirements. They were being relegated to off-road and track use — as either motocross machines or track-only race bikes, with street legal bikes an impossibility in the US and Europe in the face of the new restrictions. Two strokes, by their very design, are nasty polluters. Not only because of the mix of oil and fuel required to lubricate the bottom end, but also by the nature of a two-stroke cycle.

You might want to skip over this next bit if you get bored to death by technical theory.

A two-stroke operates by simplifying the usual four stroke cycle. Four strokes are «suck-squish-bang-blow» — intake charge of air and fuel on down stroke, compression stroke up, ignition and push of piston back down, exhaust stroke up to expel gasses. Valves in the top of the combustion chamber open to let the fuel/air in, close to allow compression and ignition, then open again to let the exhaust gas leave. Repeat. Two strokes have two cycles — suck/blow-squish/bang. The «valves» are open ports in the walls of the cylinder, routed through the crankcase. When the piston goes down, it pulls fuel mix in on one side of the chamber while simultaneously forcing exhaust gas out the other side. When it goes up, the chamber is sealed, compression is made, ignition, piston goes back down. Repeat.

The advantage of strokers is far more power per displacement than a four stroke of equivalent displacement. Sometimes double — a 500cc two stroke is roughly equivalent to a 1000cc four stroke. But in a much lighter and simpler package. Hence why the V-Due was so hotly anticipated — here was a lightweight super sport with top shelf components that could eat bigger sport bikes for breakfast. It was hyped up to be the closest thing to a road legal GP bike since the RG500 and NS400R bowed out in 1987. In fact, it was touted as a legitimate GP bike for the road — the original V-Due was a racing project that was later switched to a road bike program. Power was expected to be 110hp in a bike that weighed just over 300lbs — remarkable numbers for the mid 90s, when a typical super bike was easily 450-500 lbs.

The disadvantage of ‘strokers is short service life (frequent bottom end rebuilds) and terrible emissions. Up to this point two strokes used carburetors — a carburetor will flow fuel constantly, even when the throttle is closed, because it delivers fuel based on the vacuum of the intake. The most strictly controlled emissions are usually unburned hydrocarbons (unburned gas) making its way into the exhaust. It’s a problem on four strokes as well. Two strokes are especially bad because the exhaust and intake ports are open at the same time — so raw fuel mix will always flow across and get into the exhaust no matter how carefully you tune the engine.

Still awake? Good, back to the Bimota.

Why was the V-Due the only game in town, and why was it so anticipated? Because Bimota claimed they had fixed the emissions issue by developing a fuel injected two-stroke with electronic ignition, something that had never been done in a motorcycle before. Direct fuel injection delivers a jet of gas when needed into the cylinder, and shuts off completely when it isn’t — unlike a carburetor. You can time fuel delivery precisely so it won’t slip through the combustion chamber and into the exhaust, and the electronic ignition can time the spark to ensure a full burn. The V-Due also used forced lubrication for the bottom end, with only minor oil mixing required to lubricate the pistons. It was topped off with a trick cassette gearbox and dry clutch, racy stuff for a road bike. So, some revolutionary technology and clever engineering and the two-stroke lives to fight another day. All eyes were on Bimota, and some early press reviews praised the handling and power the V-Due was going to offer.

With this kind of hype, disappointment was inevitable. And boy, was the V-Due a disappointment when it hit the market.

The first production models arrived in 1997 and right away major problems became apparent. Yes, they passed emissions testing and the bike was 50 state legal — but the fuel injection system was not at all sorted out, and the bikes were almost completely un-rideable. Throttle response was terrible, the engine hunted badly at steady speeds, and power delivery was extremely violent and only came on at the top of the rev range. While it was light and quick, power wasn’t up to snuff among the crop of high powered super bikes that began to emerge in the late 90s. Aside from being despicable to ride it also had electrical faults, a tendency to foul spark plugs, and had some major mechanical faults that led to piston and crank seizures. Oh, did I mention that this half-baked Italian cost about $30 000 (Ј14500)? Yeah, that definitely did not help the reputation — especially among UK magazines where writers have a penchant for being brutal in their reviews when something doesn’t measure up.

Читать еще:  Мотоцикл Phantom 50 Capirex (2007): технические характеристики, фото, видео

It wasn’t all bad. While the in-house engine design (built by Moto-Morini) was more or less a turkey, the chassis was brilliant. It looked sexy and had stellar handling, helped by a dry weight right around 320 lbs. Front suspension was courtesy of Paoli, rear by Ohlins. Brembo Goldlines took care of stopping power. Carbon fibre was used liberally. It looked the business and could find its way around a track, even if it didn’t run properly. Like many Italian motorcycle fans have said since time immemorial — it’s brilliant, when it’s working.

It quickly became clear that the V-Due was a liability for Bimota. They began accepting returns and in 1998 they release the Evoluzione upgrade — which ditched the wonky fuel injection for a pair of 39mm Dellorto carburetors. Suddenly the modus operandi of the V-Due (introducing modern FI to two strokes) was ditched in an effort to simply make the thing work. But it was a case of too little, too late. Bimota went bankrupt in 1999, after having produced 340 V-Dues of the proposed 500 example run, 21 of which were the Evoluzione.

But all was not lost. One of the project engineers, Piero Caronni, bought the remaining bikes and spares when the company went into receivership. He subsequently began modifying and fixing the issues, culminating in the Evoluzione 03, Evoluzione 04 and Edizione Finale models — introduced in 2003 and 2004. All used carburetors and modified engines with much improved reliability. Power was up as well, to 120 hp for the 03 and 130hp for the 04 and Finale. These sorted bikes have a strong cult following, with dedicated owners who are quick to dismiss the bad reputation surrounding these machines.

1997 Bimota 500 V Due

Bimota’s Ground Breaking, Two-Stroke Rocket

Early next year a milestone will be written into the history books when series production starts on the first two-stroke motorcycle in more than 10 years to meet the EPA requirements of all 50 states in the USA, and anywhere else in the world for that matter. And what a motorcycle it will be. Bimota, the constructors of the most exclusive sport bikes in the world, will unleash their 500cc two-stroke V-twin, dressed to kill in full race-tech livery. This bike will have sport riders’ pulse rates racing into overload — before they even get into the saddle. The Due will obviously be competing for the title of Ultimate Sports Machine.

Bimota has spent over six years developing this wonderful piece of machinery, not surprising since the R&D department has never had more than single figure staffing levels. Traditionally Bimota has borrowed powerplants from their Far Eastern industrial colleagues and wrapped them in exquisitely crafted frames and bodywork. Recent Bimota models have seen increasing applications of fuel injection to the engines, and this has served as the proving ground for the development of the Direct Injected two-stroke engine.

With their roots in racing, Bimota initially hoped to develop the engine for use in GPs, encouraged by the debate within the sport early in the decade about banning 4-cylinder configurations. Fortunately for all of us, the level of investment to develop a complete new bike for GP racing forced a change of direction that resulted in the imminent arrival of the street machine.

The Due will obviously be competing for the title of Ultimate Sports Machine.

Interest in two-stroke power plants has been widespread within the motorcycle and auto industry for the last 10 years, sparked by the development of a new breed of fuel injectors by the Australian company Orbital. The new system provided a granularity of fuel atomization that made their application in a two-stroke engine a practicality. Two-strokes are of interest to the automotive industry due to their simplicity and high power-to-weight ratio — if only they weren’t so dirty and fuel inefficient. Both these phenomena are caused by the two-stroke principle of using fresh, fuel-rich intake air to clean or scavenge the cylinder of exhaust gases. The tuned exhaust systems try and prevent much of this charge from escaping out of the cylinder with the exhaust gases, but a lot still does. With direct injected fuel, this is no longer a problem as air can be used to expel the exhaust gas, and the injectors only fire at the moment the exhaust ports have closed. Result is nice clean exhausts, free of unburned hydrocarbons, and un-polluted clean fresh charge waiting for the big bang of the next ignition pulse. Two-stroke heaven. Bimota has a simple slogan they claim is at the heart of all their R&D work — Tecnologia dell’Emozione.

Too good to be true, right? Well, just a little. Honda tried some fuel injection on their NSR500 GP machine during 1993, but it was dropped after that season. Surprisingly they chose to inject into the crankcase in a straight emulation of the operation of a carburetor, and as a result found similar performance to a carburetor. This could have been forced on them by the very short time that is available for fuel atomization in an engine turning at 13,000 rpm. Uneven or incomplete atomization would result in uneven or incomplete ignition and lower top power output. The Bimota Due has quoted maximum power develop at 9000 rpm and the difference in engine speed may be just enough to eliminate this problem. Interestingly, the new Honda NSR500 V-twin racer delivers its maximum power of 135 bhp at 10,250 rpm, pumping AVgas through conventional carburetors.

Talking to the Bimota staff at the recent IFMA show in Cologne, they made it clear they wanted to start production as soon as possible, and were hoping for an initial production run of 500 units.

The exact configuration of the fuel injection system is not yet known for the Bimota, but it seems that they have chosen to scavenge the exhaust gases by pumping fresh air through the crankcase and the conventional two-stroke transfer ports. Reed valves are still used to regulate the flow of air into the cylinder, each cylinder being supplied through a separate reed block. There are six transfer ports and three exhaust ports, a common configuration for contemporary two-strokes. The fuel injection system will be linked into an engine management system that checks many of the factors that influence the amount of fuel to be injected, including air temperature, water temperature, exhaust gas temperature and airbox pressure.

Another major contribution to the clean exhaust of the Due is the use of the gearbox oil to lubricate the main bearings, rather than relying on the fuel/oil mist of regular two-strokes. Cylinder and crankshaft lubrication is still performed by two-stroke oil, flowing down small galleries into the guts of the engine. There is a two liter oil tank partition to the fuel tank that will need very infrequent topping up.

The racing heritage of the machine is obvious, with a hydraulically-actuated dry clutch and 6-speed side-loading cassette gearbox that will come in handy if you want change your gearing for your favorite set of curves. The frame follows Bimota’s recent preference for oval profile alloy pipes, with an Ohlins rear shock and 46mm Paioli fully adjustable front forks. Carbon cans keep the exhaust note muted and carbon fiber is also used for the seat. Brembo discs, Antera alloy wheels and Michelin Hi-Sport radial tires complete the list of top range equipment.

Talking to the Bimota staff at the recent IFMA show in Cologne, they made it clear they wanted to start production as soon as possible, and were hoping for an initial production run of 500 units. This may not seem like a lot, but when you consider that last year Bimota produced less than 1500 bikes, it represents a massive part of their operation. Further questioning revealed that the bike was quite literally not ready for the show until the last minute, and some inconsistencies between spec sheets suggest that it may not yet be ready for full production. On the other hand, now that the project has got as far as it has, Bimota will want to start production as soon as possible to start recouping the enormous investment they have made in the new engine technology.

Bimota has a simple slogan they claim is at the heart of all their R&D work — Tecnologia dell’Emozione. In the 20 years since their first Kawasaki powered KB1 production bike, Bimota’s motorcycles have played havoc with the emotions of the world’s sport bike community. The 500cc Due proudly carries this tradition through to the closing years of the decade.

Result is nice clean exhausts, free of unburned hydrocarbons, and un-polluted clean fresh charge waiting for the big bang of the next ignition pulse. Two-stroke heaven.

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