Saab didn't license the DKW triple, they copied the DKW twin and then added an extra cylinder later :lol: The Ursaab gas tank says Auto Union on it
Freewheel is great because you don't need to use clutch to shift if you know what you are doing, so screw VW and all this bad DSG super-fast gearshift stuff, Saab had it in the 1950's!
Any one remember 96 freewheel?!
It works like the rear hub on a bicycle. You know how on a bicycle, you can pedal and it turns the back wheel via a chain... but when you're coasting, the wheel spins freely but the pedals don't turn...? The saab freewheel does exactly the same. When you're applying power via the engine, the freewheel hub (inside the transaxle) locks up and transmits the power to the wheels. Once you've got some momentum, you can lift off the gas -- the freewheel hub spins freely, and the car will coast along just as if you had put the tranny in neutral.
Why did SAAB install this mechanism? It originated in the era of the 2-stroke engines, in which the moving parts were lubricated by oil mixed with the gas. Without freewheel, if you were coasting down a mountain with your foot off the gas, the engine could be turning several thousand RPM with the throttle completely closed, meaning almost no oil would be getting to the moving parts. With freewheel, the engine drops off to idle as you coast, reducing engine wear.
This was no longer an issue once SAAB introduced 2-stroke engines with oil injection, as well as the conventional 4-stroke engines in subsequent models. So why did they keep the freewheel? There are a lot of speculations on this. Saab had advertised freewheel as an advantage, so maybe they didn't feel they could back away from it. They claimed it improved fuel economy a bit (which it does, slightly.) Some customers liked the smoothness and quietness it provides -- lift off the gas and there's no jerk of engine braking, and the engine noise drops off. Best of all, it allows you to downshift without using the normal clutch -- when you lift off the gas, the freewheel disengages drive, so you can just move the lever into a lower gear and then bring up the throttle again. This is really convenient in city driving , where you're always having to slow down for corners and then pick up again.
So if it was so great, why did they drop it? Well, it did add cost, without being seen by most potential buyers as a big benefit; it confused some drivers; and, well, it was one more thing to break, and occasionally it DID break -- immobilizing the car and requiring removal of the engine and transmission to fix. In fact, you find a lot of cars now on which the freewheel failed and was permanently locked.
Why did SAAB install this mechanism? It originated in the era of the 2-stroke engines, in which the moving parts were lubricated by oil mixed with the gas. Without freewheel, if you were coasting down a mountain with your foot off the gas, the engine could be turning several thousand RPM with the throttle completely closed, meaning almost no oil would be getting to the moving parts. With freewheel, the engine drops off to idle as you coast, reducing engine wear.
This was no longer an issue once SAAB introduced 2-stroke engines with oil injection, as well as the conventional 4-stroke engines in subsequent models. So why did they keep the freewheel? There are a lot of speculations on this. Saab had advertised freewheel as an advantage, so maybe they didn't feel they could back away from it. They claimed it improved fuel economy a bit (which it does, slightly.) Some customers liked the smoothness and quietness it provides -- lift off the gas and there's no jerk of engine braking, and the engine noise drops off. Best of all, it allows you to downshift without using the normal clutch -- when you lift off the gas, the freewheel disengages drive, so you can just move the lever into a lower gear and then bring up the throttle again. This is really convenient in city driving , where you're always having to slow down for corners and then pick up again.
So if it was so great, why did they drop it? Well, it did add cost, without being seen by most potential buyers as a big benefit; it confused some drivers; and, well, it was one more thing to break, and occasionally it DID break -- immobilizing the car and requiring removal of the engine and transmission to fix. In fact, you find a lot of cars now on which the freewheel failed and was permanently locked.
I was looking after my mums Corgi once, which had the annoying habit of burying itself under the seat when in a car.
This particular day it buried itself under the drivers seat, there I was happily driving along when someone turned out from a side junction and then stopped to do a U turn back into side road.
I slammed the brakes on, guess what happened?
dog gets thrown out from under seat, and ends up jammed lengthways under all 3 pedals!
no brakes, no clutch and its in freewheel
Heading toward stationary vehicle at 40-50 mph and no way of stopping;oops:
Somehow managed to drag dog out whilst keeping control of steering wheel, slammed freewheel lever back in (its right at front of footwell under dash) and kept hold of steering wheel all at same time.
Any one else had a similar experience?
I wonder why cars don't have freewheel any more
??!used to hate the fact that when you came to a hill there was no engine braking! He used to sit rigid clinging on to anything he could! This was the guy that totalled his 325 BMW by clipping a bridge at 80mph and rolling it 3 times into a field!
Plus of course you can left foot brake too!
It also must be the only car you can drive home if your clutch fails! You can start the engine with first gear engaged and (with a bit of kangarooing) drive off. Then you don't need to use your clutch after that, just kill the engine when you come to a halt!
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