6 cyl K (more is more?)

[Bob Hancock]

I think the latest Cycle World has an article on the 6 trilogy.

[cageyar]

Originally Posted by NakedRider

Yep. I believe it was called the Sei. Started as a 750 and if memory serves me correctly it grew into a 900. All of this well before the CBX.

Yes, the Benelli Sei came out before the CBX, but it was more like the SOHC Honda CB500/550 with two additional cylinders.
The CBX was DOHC, 4 valves per cylinder with the alternator/ignition running off a jackshaft driven behind the cylinders. Honda kept the width reasonable that way with nothing on the ends of the crank.
The CBX was a drawn out, tortured release not unlike BMW does occassionally; shown in the press and at shows long before it's actual release. By the time it did come out, the Suzuki DOHC GS1100 has eclipsed it in terms of performance.
Honda had something unique but kind of really botched the whole affair-the CBX was made for just 4 model years-1979 through 1982.
The 1979 model was the "lightest" at just under 600 lbs. But to get there, Honda made everything too light: plastic swingarm bushings, 35MM fork tubes and narrow rims/tires. with 103 HP at the crank, not exactly a "handler".
The 1980 model was the worst. They beefed up the swingarm with real bearings and used a wider rear wheel, but due to fuel consumption/emission concerns, the engine was detuned with less cam duration and ignition advance. Now it was a 600+ pound good looking slug with low 90's HP and an 85 MPH speedo.
With sales plummeting, Honda turned the CBX into a "sport tourer" for 1981-82 with an added fairing and color matched bags, restored some HP, added Pro-Link rear suspension and 39MM fork tubes. Now it was about 635 lbs.
I've had my 1982 since new-it was my rep bike when I was a Honda DM. I stripped off the fairing, never used the bags, installed the Euro-only low bars and rear sets, added the '79 "hot" cams and ignition advance as well as the '79 carbs with primary and secondary mains (I have a new, spare '79 engine) and swapped the incredibly bad Pro-Link rear air shock for a Work Performance emulsion unit. I also made a six into two exhaust system with VF750 Super Trapp silencers and a 140MPH speedo. I've enjoyed it over the years, but this winter, it's getting spruced up and going on eBay:

[Pete B]

Originally Posted by RoLoo

...I think it looks more like the 2005 Suzuki Stratosphere...
...also an in-line six...


...Stratosphere pictures...

...and more... (click on the Stratosphere button)

I see this



and God help me, I don't know why - maybe the back end - I see a bit of this



Cheers,

[peter f]

Αnd this is the real-life pipework configuration for luxury tourers/tourers (I-6 LT etc).

[EenyBear]

I had a Kawa KZ1300 for a while some years ago.
Even though it was a heavy pig with insufficient brakes... the smooth continuous power of the 6-cylinder engine was intoxicating. This one might be fun.

[shreddr]

Originally Posted by peter f

Αnd this is the real-life pipework configuration for luxury tourers/tourers (I-6 LT etc).

that actually looks pretty sporty. if those were Akra canisters it would be rocking!

[turboflyer]

I bet that thing will sound like an Indy car. That interest me much more than the R1000. Given the pipes are well loud enough.

[cageyar]

Originally Posted by turboflyer

I bet that thing will sound like an Indy car. That interest me much more than the R1000. Given the pipes are well loud enough.

I've always described my CBX with the Super Trapps as a poor man's Ferrari.
At 6,000 RPM it wails.

[peter f]

Originally Posted by cageyar

I've always described my CBX with the Super Trapps as a poor man's Ferrari.
At 6,000 RPM it wails.

Ferrari? > here it is (kinda) > a Greek V12 (chrome orgy is kitsch to the max...not to mention the whole design, but stick to 2*CBX motors).

Honda V12 CBX by Andreas Georgeades

[cageyar]

Originally Posted by peter f

Ferrari? > here it is (kinda) > a Greek V12 (chrome orgy is kitsch to the max...not to mention the whole design, but stick to 2*CBX motors)

That bike is insane!
Perhaps I should have said very poor man's Ferrari.
Mine does sound great at high RPM.
Knowing what mine is like to corner (you need a winch to crank it over) I can't imagine what a bike with 2 CBX engines feels like-each one weighs 203 lbs.

[peter f]

Originally Posted by cageyar

Perhaps I should have said very poor man's Ferrari.

OK, get this > Ferrari for those with a total loss of (any kind) taste.

Moral: when I become Emperor of the World (soon, I do hope) I'll lobotomize 99.99% of designers. No Mercy !

[shreddr]

when i clicked on that link all i saw was the chrome excess, i didn't see the V12, holy sheeet! surely it has more top end capability than that chassis is prepared to handle!

[EenyBear]

For those that might have missed the tiny link... here is the YouTube clip of the V-12 and some pretty candid background discussion.

This film clip was probably pretty close to the maiden run for the bike - they're still talking about some strange noises, how to get rid of them, ... and either the rings haven't seated yet or things are smokin' hot.

Awesome engineering.

YouTube - V12 CBX running down the road (alley)

Cheers,
Ian

[EenyBear]

As I have a passing familiarity with certain Italian cars... I would be pleased to test ride that "Ferrari" motorcycle pictured above - if it ever became reality. The Enzo and the Gallardo - for example - look somewhat different from a more domesticated automobile and I can tolerate a Ferrari concept motorcycle looking somewhat different from my R1200S.

Truly, to each their own. I kinda like it. There, I said it out loud.

[rjo]

Originally Posted by EenyBear

... and either the rings haven't seated yet or things are smokin' hot.

Awesome engineering.

YouTube - V12 CBX running down the road (alley)

Cheers,
Ian

As the builder got off the bike and walked past the back he commented that the paint was burning off the exhaust, os yeah, it must have been pretty much its first run.

[peter f]

BMW TV - BMW Motorrad Concept 6

[turboflyer]

Peter great link. Dang that concept 6 could just move me on to more than two pistons. Nice, but no doubt will be stupid money.

[CARacic]

I had a 900 sei. That bike was all about the motor really smoooooooooth. But under 45 degrees it needed starting fluid to start from cold. Between the seat and suspension the ride under 80 mph was tough featuring butt burns after an hour. I replaced it with an '85 k100rs, the motor wasn't as nice but the rest of the bike was better and I really liked lockable and detachable hard bags.
I think BMW had to show this bike now, the K1200LT was long in the tooth several years ago and this can generate some excitement. Perhaps they may sell something like the Concept 6 as a platform to introduce the new motor ala HP12. Really this is the platform for the new LT. A modern 6 with ESA chassis and all the other electronic safety options could be a sweet ride. But when are they going to bring gasoline direct injection to bikes?

[peter f]

Originally Posted by CARacic

But when are they going to bring gasoline direct injection to bikes?

Good question (read this, but I forgot/lost the source/link)

Direct Gasoline Injection for Motorcycles

The fuel injection in motorcycles has a big influence on the behavior of the engine in terms of performance, emission, fuel economy and driveability.During the last years Direct Gasoline Injection (DGI) has been developed to readiness for start of production and has been introduced to several passenger cars. The major aim when talking about DGI for passenger cars is the improvement of fuel consumption.

However motorcycles have to fulfil different target specifications which are comparable to application of DGI for racing.The potential for performance increase by using DGI is shown in picture 'Potential for performance increase by using DGI'. Beside a slightly increase in engine power DGI offers additional potential to improve the engine behaviour.

Improvements by using DGI:

higher engine performance due to increased volumetric efficiency
improved driveability
possibility of fast traction control
improved emission behavior by avoidance of wall film (picture 'Wall film of engine with PFI') and reduced HC emissions during valve overlap (picture 'HC emissions during valve overlap')improved fuel economy, extended range

A special challenge when applying DGI on motorcycle engines is the wide engine speed range of these engines.The following pages describe the characteristics to be taken into consideration when applying DGI on high performance and high revving motorcycle engines.

High Revving DGI Engines

In order to utilize the whole potential of DGI and to avoid any shortcomings the injection has to take place in a certain window of the operation cycle. More precisely is has to be ensured that no moving parts like piston or valves are impinged by the injection spray and that there is sufficient time for mixture formation before ignition. These boundary conditions are shown in picture 'Optimal injection timing and limitations by piston impingement and homogenization problems due to late injection (PFI = Port Fuel Injection)'.

Above mentioned considerations lead to an optimal injection window for each engine operation point. Picture 'Injection timing' shows this window of opportunity and the resulting available injection time for full load operation over engine speed. Due to the limited time for injection at high engine speed a high flow rate of the injector is required to provide the amount of fuel which is required at wide open throttle (WOT) and rated speed. On the other hand at idle operation or low load a small amount of fuel has to be provided without major deviations. Therefore special injectors and a modulated fuel pressure are required see picture 'Dynamic range of injector'.

DGI - PFI

A comparison of Direct Gasoline Injection (DGI) and Port Fuel Injection (PFI) shows that both concepts offer advantages for certain operating conditions.

PFI provides a homogeneous mixture due to the longer time which is available for mixture preparation. This ensures a good and stable combustion. As already mentioned DGI is advantageous in terms of driveability and transient engine behavior, leads to an increased volumetric efficiency, ensures lower emissions and a higher compression ratio can be realized which leads to a higher performance.

So it is logically to make use of the advantages of both concepts by a combination of DGI and PFI. In picture 'Optimal ration between DGI and PFI for maximum performance' the optimal ratio between DGI and PFI for maximum engine performance and the possible performance increase for one operating point by DGI - PFI compared to DGI only or PFI only is shown. This ratio is different for each operating point. The possible performance increase over engine speed by DGI - PFI is described in picture 'Performance increase by DGI - PFI'.

Picture 'DGI - PFI engine concept' shows a V2 engine concept with one top feed injector and one direct injector per cylinder. The direct injector is placed under the intake port between the intake valves.
Using two injectors is also advantageous to cover the required dynamic range from idle operation to wide open throttle at rated speed.

Driveability - Traction Control

A precondition for a fast lap time of a motorcycle is an engine which can be controlled by the rider easily. The behavior of the engine is influenced by the engine concept, firing order and various devices which give the possibility to realize a traction control. One example is an electronic throttle actuation (drive by wire) which offers the possibility to overrule the rider’ s input via the throttle grip.

Further solutions to realize a traction control are enleanment of the mixture, spark retardation and retardation of start of injection (SOI) of a direct injected engine.

When varying these parameters it has to be considered that the exhaust gas temperature does not exceed a certain limit. As shown in picture 'Fast traction control by varying of different parameters' SOI retardation of a DGI engine provides the widest adjustment range before the limitation given by the exhaust gas temperature is reached. Therefore DGI offers the most effective fast traction control.

Beside the target to achieve the fastest lap time a traction control is also a safety feature for less experienced riders. Under consideration of the steadily increasing performance of motorcycles offered on the market this feature may become indispensable in the near future.

Generally DGI leads to an improved driveability since the transient engine operation can be controlled easier. The reason is very simple. DGI provides the fuel where it is needed - in the combustion chamber. Therefore the element of uncertainty caused by the wall film (picture 'Area covered by wall film; 4 - stroke engine with PFI') in the intake ports is eliminated.

Design Concepts

Naturally aspirated high revving high performance engines are characterized by some characteristic design features. In order to achieve the desired performance optimized ports, a compact combustion chamber with central spark plug position and maximized valve size are necessary preconditions.

When applying an injector for direct injection it has to be considered that above mentioned design features are not influenced negatively. Depending on the layout of the cylinder head the injector position has to be optimised under consideration of the above mentioned boundary conditions. The analysis of various injector positions leads to the result that the optimal injector position for a 4 - valve engine is between the intake valves and below the intake port. A steep intake port as it is common for high performance engines is very advantageous for this layout. Furthermore it has to be considered that the shape of the combustion chamber is not disturbed by the application of the injector.

The fine tuning of the injector position and the inclination of the injector has to ensure that no impingement of the spray on cylinder wall and piston occurs. Special attention has to be paid on the moving parts like piston and valves.

The consideration of these guidelines during the design is imperative to avoid oil dilution, soot formation and carbon deposits and to ensure a trouble free engine operation.

During the design many accompanying work steps like simulation, hardware test and flow tests ensure an optimized engine design.

[peter f]

OK,

The Whale...er...I mean the Eagle has landed (ETA 2011). More gizmos than a Madonna show and some Kwak 1.4 GTR style.

Is it available in pink? (I yes, I could be tempted).