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Fastest shifting possible plus fuel economy gains

Dual clutch transmission systems have been increasingly adopted by automobile manufacturers as a way to increase performance and fuel efficiency at the same time. DCT is a semi-automatic transmission with two separate clutches for odd and even gears. One clutch drives the odd numbered gears, while the another clutch drives the even numbered gears. This setup eliminates the torque converter used in traditional automatic transmissions and allows a computer to shift more smoothly and quickly than is humanly possible. However, the option for manual shifting is still available, and many companies have paired DCT systems with paddle-shifters.

Volkswagen already has DCT available in the Jetta, Passat, Golf, Rabbit, and Touran, while the Audi A3, S4, and TT have it available as well. Ricardo makes a seven-speed DCT for the 1001 horsepower Bugatti Veyron, and Porsche is replacing its Tiptronic transmission entirely with its DCT system named PDK.

VW, Audi, Bentley, Bugatti, Lamborghini, SEAT, Skoda, and Scania are all part of the Volkswagen Group, ranked as the third largest auto maker in the world. Porsche is set to join their ranks in 2011 as part of a merger agreement. Collectively, the VW Group is the largest adopter of DCT systems and is looking to make DCT an option across their entire product range.

Ford and Mazda are also planning to get in on the DCT action. Ford is branding their version of DCT under their PowerShift label, and will start using it in the Focus and Fiesta. Mazda is planning something similar across their entire product line by 2015.

Honda is starting small with their entry into the DCT market. The company has shown off the world's first DCT system for motorcycles, and will introduce it in large displacement sport bikes next year with the 2010 VFR1200F. Honda claims that they have come up with a light, compact design that allows it to be combined with existing engines without substantial layout modifications.

Traditional dual-clutch transmissions tend to be too bulky for motorcycle use, so Honda's system is designed to be extremely compact. The new system employs original technologies such as dual input shafts, exclusive in-line clutch design, and concentration of hydraulic circuitry beneath the engine cover to achieve a compact design. Compactness and low weight is further enhanced through the use of a simple shift mechanism design based on that of a conventional motorcycle shift drum.

In order to respond to rider demands in a broad range of situations, the transmission is equipped with three operating modes. There are two fully automatic modes (D-mode for regular operation and S-mode for sporty riding), and a 6-speed manual mode which delivers the same shift feel as a manual transmission. Honda claims that optimized shift scheduling achieves fuel economy equal to or better than that of a fully manual transmission, enabling their DCT to deliver both sporty riding and environmental performance combined.

The VFR1200F also features anti-lock brakes (ABS) as standard equipment, as well as a dual combined braking system (CBS) shown in previous generation VFR motorcycles.

The new transmission has 100 patents pending, and is claimed to provide "sporty riding enjoyment with easy operation". Honda intends to gradually expand the deployment of the new DCT system to more of its large displacement motorcycles over the next few years, focusing particularly on sport models destined for use in developed countries.

Honda CEO Takeo Fukui stated in May that Honda was working on a new system that could be matched with future hybrids. The Honda Fit already has a paddle-shifter option, and the company has already announced that production of the Honda Fit Hybrid would begin before the end of 2010.



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Main issue
By FITCamaro on 10/19/2009 9:18:08 AM , Rating: 2
While the technology is certainly impressive, the main things people who like manuals have against any automatic is that they are heavier, more complicated, costlier, and rob more power than a traditional manual transmission.

Sure the computer might be able to shift faster than me, but I love banging through the gears of my GTO myself. Feel far more connected with the road and I find it helps you remain more focused on driving.




RE: Main issue
By Spivonious on 10/19/2009 9:25:08 AM , Rating: 3
Not to mention the added benefit of using the engine to control your speed rather than the brakes.

Manual transmissions make me feel like I'm more in control of the vehicle.


RE: Main issue
By FITCamaro on 10/19/2009 9:26:59 AM , Rating: 3
Yeah I typically engine brake before I apply my brakes when coming up on a light.


RE: Main issue
By headbox on 10/22/2009 3:56:12 PM , Rating: 2
engine braking is not the preferred method- why put extra wear and tear on your engine instead of some cheap, easy to replace, brake pads?

A lot of modern sport machines advertise low or no engine braking, and 2-stroke engines have almost none.


RE: Main issue
By SublimeSimplicity on 10/19/2009 10:00:55 AM , Rating: 5
I don't see why you couldn't engine brake a dual-clutch. At the end of the day, it's just two manual transmissions linked together. Once dual clutch transmissions start using dry clutches, the only reason to offer a manual will be for people who just like them.

Personally I don't see why someone would choose a manual over a DSG if the performance was worse (acceleration and fuel econ), the control was the same, and the convenience in traffic was much worse. It would be like choosing manual windows over electronic windows because you like to control the speed the windows roll up.


RE: Main issue
By Brandon Hill (blog) on 10/19/2009 10:01:17 AM , Rating: 2
Agreed. The only difference is that you're not moving the shift lever a great distance and there's no clutch to operate yourself. Otherwise, you're still controlling the engagement of the gears with either the "flappy paddles" or the console shifter.


RE: Main issue
By Spivonious on 10/19/2009 11:15:07 AM , Rating: 2
The clutch is my favorite part. Choosing gears is secondary. I think we'll see these new dual clutch thingies replace or supplement automatic transmissions. Manual transmissions are already a niche market.


RE: Main issue
By Spuke on 10/19/2009 2:30:09 PM , Rating: 2
quote:
I think we'll see these new dual clutch thingies replace or supplement automatic transmissions.
That's what most manufacturers are doing currently.

quote:
The clutch is my favorite part. Choosing gears is secondary.
Shifting does it for me. I can do without the clutch pedal. My next car will have a DCT.


RE: Main issue
By slawless on 10/19/2009 10:28:13 AM , Rating: 2
Why do I drive a manual? Given my ability as a driver (or lack there of) I have no doubt a well programmed DCT will out shift me. However driving a high performance car is the experience of driving it. It is just a a great feeling of letting off the clutch and feeling the car blow you back in the seat, chirping the tires between gears. The manual keeps me involved in driving the car. MY current car, an M3, has "drive off assist" it hold the car on a hill when you start. it works prefectly but I would perfer to do it myself.


RE: Main issue
By Brandon Hill (blog) on 10/19/2009 10:31:40 AM , Rating: 2
Then I guess you'll never "fully" experience high(er) performance sports cars, because most of them have DCTs or are switching over to them ;)


RE: Main issue
By Samus on 10/20/2009 12:16:13 PM , Rating: 2
Point A--
2004 R32 6-speed clutch/flywheel/slave cyl replacement: $600
2008 R32 DCT clutch pack: $1400

Point B--
2004 R32 clutch replacement hours: 4-6
2008 R32 clutch pack replacement hours: 7-8

Point C--
2004 R32 clutch maintanance interval: 120,000 miles
2008 R32 clutch maintanance interval: 80,000 miles

*most DCT clutch packs have a very small surface area. even though these are 'clutchless' and the computer shifts them very fast with little wear, simple physics prevail.

As with everything German, it seems they often take a simple, proven design and make it complex and unreliable. Sure, there are often technological benifits, but I don't see dual mass flywheels, interference engines, timing belts (opposed to chains, something the Japanese are actually returning back too) and more plastic/less metal as a neccessarily optimal approach to the future of vehicle developement :(


RE: Main issue
By SublimeSimplicity on 10/19/2009 10:42:51 AM , Rating: 4
You know those car guys who resisted the switch to electronic fuel injection and ignition?

They enjoyed to tweak this screw or that screw on their carburetor and change the advance of their ignition when the temperature changed 10 degrees. They looked down on you as not a "real" car guy because you weren't as connected to your machine.

You would laugh and laugh at them, as your car just started no matter if it was 100 degrees outside or 20 below... whether you had just driven it or let it sit for a month. You had equal if not better performance with infinitely less effort... but at the expense of not being completely in control.

Watch out, because you're becoming that dinosaur you used to laugh at.


RE: Main issue
By theapparition on 10/19/2009 11:19:52 AM , Rating: 2
Well said.

DCTs are here to stay and will eventually replace manuals for the majority of cars. While some of my cars are still stick, and I love rowing through the gears, I don't look down on automatics like some do. Little changes like a high stall TC, and an Auto will consistanly beat a manual any day of the week, reguardless of higher parasitic loss. In the end, that's what your looking for in a performance car. Who cares about dyno numbers, the only thing that matters is real world numbers.

The only advantage manual transimissions have now are on road courses, where lack of individual gear selection hampers driving. With paddle shifts and DCT, this is a thing of the past.


RE: Main issue
By Spuke on 10/19/2009 2:32:33 PM , Rating: 2
quote:
DCTs are here to stay and will eventually replace manuals for the majority of cars.
Currently, DCT's are replacing auto's not manual transmissions.


RE: Main issue
By lightfoot on 10/19/2009 6:29:35 PM , Rating: 2
I don't look down on automatic transmissions, I look down on automatic transmission drivers. Why? When you take the physical effort out of driving, people automatically remove the mental effort from it too. If I have a clutch to operate with my left foot, and a transmission to operate with my right hand that is one less foot and hand I have for sending a text message, eating, or fixing my hair with. And that is NOT a bad thing.

How fat and lazy do we have to get when operating a petal is too difficult to travel 20 miles?? A clutch pedal still beats the hell out of walking or even riding a bike. How many drivers today don't even know how to operate a clutch??

We are at the point where the only thing that the driver is responsible for is thinking, and now most drivers don't even bother with that. With all this technology, people are no better at staying on the roads and not running into things.


RE: Main issue
By Pirks on 10/19/09, Rating: -1
RE: Main issue
By weskurtz0081 on 10/19/09, Rating: 0
RE: Main issue
By The0ne on 10/19/2009 2:16:38 PM , Rating: 2
I like to shift myself but lately I have not been very impress by the clutch systems of the vehicles I've test drove. In short they are clunky and are more obtrusive than I would like them to be. They get in the way of actually shifting gears properly and timely. This alone negates any benefits others have been saying about being in control and being faster than the computer *roll eyes*

The last good gearbox I had used was in one of my relatives Eclipse GSX. That gearbox was so smooth I fell in love with it. Now, I wish I had gotten the EVO X MR instead of the GSR. But wanting to shift manually made me decide otherwise and now I'm regretting it anytime I do any type of performance driving.


RE: Main issue
By Iaiken on 10/19/2009 10:10:59 AM , Rating: 2
Don't be obtuse... Even my steptronic allows for engine breaking. :P

Basically, any shifting system that allows the driver direct control over the shift pattern will allow it. The only time my steptronic will execute an override is if I go over 7000 (rev limit is 6500) or below 1000 (in which case I am already risking a stall).


RE: Main issue
By Omega215D on 10/20/2009 3:07:08 AM , Rating: 2
When I rally race I love the idea of possibly going into a stall, it adds more to the already available tension to driving a rally car. For autosport I prefer the clutch and shift rod to anything else.

For what it's worth I operate an Audi 4000CS Quattro, and a dabble a bit with SuperBike racing on a Kawasaki Ninja ZX-6R (all amateur racing).


RE: Main issue
By DeepBlue1975 on 10/19/2009 9:28:20 AM , Rating: 2
No, these gear shifters don't diminish power. On the contrary, VW's and Audi's cars equipped with DSG or S-Tronic gearboxes, feature faster acceleration figures while reducing fuel consumption vs the same car with a manual gearbox.
Besides, the acceleration is uniform, you don't feel any creeps or drops in rpms while the shifting is done (2 gears are always engaged on these, so that the gear transition feels seamless)

I used to hate every kind of auto gearbox, but I find dual clutch ones really very appealing.

And CVT ones, well... I love the concept. And seems to be working quite allright for some nissan models like the Murano.


RE: Main issue
By Gul Westfale on 10/19/2009 9:30:37 AM , Rating: 2
a dual clutch box is not an autobox. there is no torque converter. the shifting process itself is automated, but the driver decides when to shift. they all do have a mode in which the computer can be allowed to shift on its own, but that is not the primary role of a dual clutch box.

http://www.myturbodiesel.com/1000q/dsg_faq.htm


RE: Main issue
By Calin on 10/19/2009 9:55:18 AM , Rating: 2
All the gears are always engaged in a gearbox, the input/output shafts change the gears by changing the engaged shafts (using some dog teeth gears).
There are creeps and drops in rpms, as the rpm must change when the speed stays the same (the ratio changes with the gears)


RE: Main issue
By Brandon Hill (blog) on 10/19/2009 9:28:12 AM , Rating: 2
But DCT are more often than not faster and just as fuel efficient (and in some cases, more fuel efficient) than their manual counterparts -- the added weight and power robbing arguments don't hold much water.

That being said, I guess the only professional drivers that are "focused on driving" and "far more connected with the road" are NASCAR drivers (since they have manuals) -- just about every other professional race car series uses semi-automatics and have for quite some time (at least the early 90s IIRC for F1).


RE: Main issue
By Omega215D on 10/20/2009 3:07:56 AM , Rating: 2
No, Rally drivers are.


RE: Main issue
By Calin on 10/19/2009 9:47:07 AM , Rating: 2
They lack a torque converter, so they won't rob power while running. They are heavier indeed, as they are not manually-operated, and the automatic operation uses mass. They have the added complication of one more clutch and "automagic" shifting.
Totally agree with "connected with the road" though.


RE: Main issue
By Iaiken on 10/19/2009 10:06:23 AM , Rating: 2
The only problem I have with the the technology is the balancing issues of 7-speeds that cause severe torque limitations unless the manufacturer uses exotic plate/shaft materials. This basically kills off aftermarket power tuning for such cars; instead, it forces tuners hands into widening the powerband (Twinscrolls for everyone! :)

I'd rather see widespread semi-automatic transmissions that are reliable and aren't prohibitively expensive...


RE: Main issue
By Spuke on 10/19/2009 2:36:16 PM , Rating: 2
quote:
This basically kills off aftermarket power tuning for such cars; instead, it forces tuners hands into widening the powerband (Twinscrolls for everyone! :)
I guess a 600hp supercharged M3 is not "power tuned" to you?


RE: Main issue
By Iaiken on 10/19/2009 8:46:47 PM , Rating: 2
quote:
unless the manufacturer uses exotic plate/shaft materials.


So glad you can read.

If it is anything like the 7-speed dual clutch assembly for the GT-R, then it has friction materials were developed specifically for that high-tensile application.

Happy failing! :D


RE: Main issue
By mmcdonalataocdotgov on 10/19/2009 11:02:46 AM , Rating: 1
Porsche has had this in production since the Mid-1980's.


RE: Main issue
By mmcdonalataocdotgov on 10/19/2009 11:10:40 AM , Rating: 2
From MotorAuthority when Porsche announced PDK production in June 2007:

quote:
The sports carmaker used the design for some of its race cars during the 1980s, and now it’s set to be available in Porsche’s production cars, as reported by What Car? magazine.


RE: Main issue
By jjmcubed on 10/19/2009 7:57:11 PM , Rating: 2
Not in a production car unless you count the 962 as a production car... They have used them in race cars since the mid 80's


RE: Main issue
By corduroygt on 10/19/2009 5:49:20 PM , Rating: 3
I love shifting for myself as well, but a GTO is not the best example for a fun manual transmission. I had more fun shifting a honda fit.


RE: Main issue
By lco45 on 10/19/2009 6:53:38 PM , Rating: 2
I think the system can allow full user control as well.
I agree, there's nothing quite like dropping back to second or third and flooring it.
Luke


RE: Main issue
By Nik00117 on 10/20/2009 4:55:43 AM , Rating: 1
Yea, I don't wanna see an automatic anything on a bike.

PLus we don't need hybrids on bikes, it's useless & costly.


RE: Main issue
By otispunkmeyer on 10/20/2009 4:56:30 PM , Rating: 2
you dont understand the way a Dual clutch tranny works

yes its automatice, but its function is exactly like a manual...so it doesnt rob power like a torque converter does and thanks to the second clutch effectively having the next gear ready to go, it can switch cogs faster than you can anyday of the week and in the right conditions is more fuel efficient

granted it might be heavier than a standard manual... but not overly so.


RE: Main issue
By inperfectdarkness on 10/21/2009 9:36:21 AM , Rating: 1
my main concern is durability. the technology is superior, but as with the CVT, the durability and ability to handle LARGE amounts of power gives me pause.

the highest hp application for a dual-clutch transmission that i can currently recall is in the GT-R--which has a notorious achillies heel with regards to the "factory advertised" launch mode. the GT-R is 480chp (crank hp).

i'd love to be freed from torque converters; however, the one advantage a torque converter has is its inherent ability to "cushion" the shock to drivetrain components that can be easily caused by directly-connected transmissions.

until and unless performance cars made with dual-clutch transmissions are proven to be capable of sustaining repeated launches, hard driving, etc, at 500whp (wheel hp) or greater--then i will stick to "old" technology in favor of reliability. this statement applies to both the transmission as well as driveshaft, axles, differentials, etc.


VFR
By Gul Westfale on 10/19/2009 9:21:37 AM , Rating: 3
the new viffer looks much better than the current VFR800, but it's incredibly heavy... more touring bike that looks sporty (like a big BMW) rather than a sports bike that can go touring. a bit disappointing.

here are full specs:
http://www.visordown.com/motorcycle-news-new-bikes...

http://www.visordown.com/motorcycle-news-new-bikes...

267kg... about 50kg too much. but some say they are replacing bot the VFR800 and the ST1300 with this one bike, so maybe the larger chassis makes sense that way, after all the ST was a popular police bike and honda may not want to lose that market.




RE: VFR
By gixser on 10/19/2009 3:42:17 PM , Rating: 2
I know its probably not the right bike to go popping wheelies on but how can you clutch up a wheelie with this technology?

Sounds like the VFR1200 is gonna replace the ST, the VFR and the old Blackbird CBR1100xx. I have the Blackbird and I've been waiting to see what replaces it. Thanks for the specs.


RE: VFR
By Gul Westfale on 10/19/2009 6:25:35 PM , Rating: 2
congrats on the blackbird. awesome machine.


RE: VFR
By Omega215D on 10/19/2009 5:33:30 PM , Rating: 2
This new VFR is said to also bring high MPG figures along with higher performance to hopefully become the top sport tourer and outshine a Hayabusa. As for me I still like the look of the VFR 800/ Interceptor because it has plenty of lighting both front and rear and the 4 into 4 exhaust (it may look like 2 but there are 2 holes on each can).

I would like them to tune the VTEC a bit more so it would be less abrupt.


It's not the performance, It's the simplicity
By ulkram on 10/19/2009 3:23:42 PM , Rating: 1
I like manuals transmissions because they cost less and are less complicated (easier to fix). The speed limit is 65mph, and I don't need to go much faster.

Do they still make cars without power steering and brakes?




By Spuke on 10/19/2009 4:23:27 PM , Rating: 2
quote:
Do they still make cars without power steering and brakes?
Not in the US. But I wouldn't call power steering and brakes complex. It's just a couple of pumps and some lines. LOL! Hardly brain surgery. Complex is the Bosch direct injection ECU software.


COST
By dijuremo on 10/20/2009 7:38:58 AM , Rating: 2
Great, now instead of having to pay ~$1000 for a clutch replacement I will have to pay ~$2000, a grand for each clutch...




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