What is a semi automatic?

it's a sort of gun! ;)

I remember a manual car without a clutch pedal being called a semi-auto, tho i can't remember what car it was...
 
So would a manual gearbox without a clutch be an automatic gearbox with manual over-ride (so a semi auto) but without the ability to automatically change gear....?
 
hmm, i think i'm wrong about my definition of a semi-automatic.

i'd have thought standard bmw auto 'boxes would count as semi-automatic as they have the steptronic, but it seems that the semi-automatic gearbox on the BMW is the SMG.
but then the VAG DSG is also classed as a semi-automatic.

if it can be used as both a clutchless manual AND a full automatic, then it's semi-automatic as far as i'm concerned..
 
What car companies brand things as and what they actually are are two very very different things.

If in a manual gearbox you have to manually manage the clutch and changing gear, and in an automatic gearbox the clutch and the changing of gears is done automatically, should a semi automatic not be something that does one of the two automatically and not the other? Wether it can do other combinations is besides the point? i.e it does half (semi) of the job automatically?

Although a semi auto that managed the gear change itself but required manual clutch would be pointless lol.
 
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A semi-automatic transmission (also known as clutchless manual transmission, automated manual transmission, or paddle shift gearbox) is a system which uses electronic sensors, processors and actuators to execute gear shifts on the command of the driver. This removes the need for a clutch pedal which the driver otherwise needs to depress before making a gear change, since the clutch itself is actuated by electronic equipment which can synchronise the timing and torque required to make gear shifts quick and smooth. The system was designed by automobile manufacturers to provide a better driving experience, especially in cities where congestion frequently causes stop-and-go traffic patterns. Like Tiptronic, many modern semi-automatic transmissions can operate in the same manner as a conventional type of automatic transmission by allowing the transmission's computer to automatically change gear, if for example the driver was redlining the engine.
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http://en.wikipedia.org/wiki/Semi-automatic_transmission

Google is your friend.
 
most quad bikes have semi automatic gear boxes (well the farm ones we've always had)

no clutch, just up/down foot peddle or up/down buttons on the left handlebar
 
bledd. said:
most quad bikes have semi automatic gear boxes (well the farm ones we've always had)

no clutch, just up/down foot peddle or up/down buttons on the left handlebar
Click to expand...

Yup. I went on a mates quad awhile ago and it was semi auto, had to lift off the accelerator, up gear then onto the accelerator again :D
 
For standard automobiles, a semi-automatic transmission is typically considered to be any transmission whereby you do not have to operate a clutch pedal. Whether the transmission itself is operating a clutch, or is a torque converter-based system, is besides the point :)
 
Quads aren't semi-auto, they've just got crash gearboxes. Constant syncromesh I think they call it, same as motocross bikes. As you said, just need to roll off.

Same with a lot of road bikes, you can get away with just rolling off the throttle and clicking it up. You can do it with cars as well. MX bikes and quads have proper crash gearboxes though, you can stomp it down without the clutch too.

Edit:

Woops, looked it up. Constant mesh and crash gearbox are completely different. Crash gearbox has no syncromesh at all, apparently. Learn something every day :D

I meant constant mesh
 
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BMW tiptronic is pretty good, makes traffic driving easy and still retains a bit of sportiness with the up/down nudges on the open road.
console.jpg
 
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LukeTW said:
Yup. I went on a mates quad awhile ago and it was semi auto, had to lift off the accelerator, up gear then onto the accelerator again :D
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yup

although with the honda atv's you barely need to easy off the accelerator, just a split second as you change, then you can rag it again
 
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