Monday, June 2, 2014

Shifting Gears

The title of this essay is “Shifting Gears.” It is not a metaphor for making life changes, nor is it an allegory about going in new directions. No, it’s about shifting gears; driving a stick; using a clutch; a manual transmission; gear jammin’.

I’ve always had a natural ability with machinery. I didn’t need a “lefty-loosey” or “righty-tighty” to get along with tools and machines. I’ve got an innate ability and a natural predilection with machinery. Oh, I can have a tough time starting a lawn mower like anyone else, but mostly machinery works well in my hands. And none better than a good old stick shift.

My first driving experience was with my dad’s ’52 Chevy Sedan Delivery, or — using the more common description — “panel truck.” Like most cars and small trucks of the ‘50s, it was a simple machine. You started it with a button on the dashboard. It did have an automatic choke, but that’s a story for another time. It had no radio. The only controls were a knob for the lights and another for the wipers. A simple heater completed the dashboard. We never used the key. In those days an ignition switch had three settings: on, off, and lock. There was a lip around the key slot, so you could turn the switch without the use of a key. We never used the key; just switching from off to on and back to off as needed. (Without the key, you couldn’t put it in “lock.”) Never locked the doors either. It was a small town. This way you never had to ask “who has the key?”

It had the common three-speed shifter on the steering column. You’d pull it toward you and down for first gear, up and forward for second, and down for third. For reverse you’d pull the shifter back toward yourself and up. It was the familiar “H” pattern of all shifters, but most modern gear jammers are used to floor shifters. Back then most levers were on the column. (If you go way, way back, the shifters were on the floor to keep the mechanism simple. Column shifters were considered very modern in the fifties.)

The mechanism was spring loaded to the forward position: second and third. You had to pull back slightly as you cleared the center of the “H” to get the low gear and reverse. It was a natural motion that the body performed more like using a hand to catch a ball or a foot to kick your brother. As you pushed the lever up from first, it would pop down into the back part of the H and continue on up on its path to second gear. It was more automatic muscle memory than thoughtful process. The center of the H was the neutral position. No gears engaged. If you put the truck in neutral, let out the clutch, and stepped on the gas, the motor would rev and race. But that had a purpose. Read on.

In those days second and third had “synchromesh” gears. These are small parts in the transmission that speed up (or slowed down) the gears during shifting to assure they meshed without any grinding. That allowed you to shift to second and between second and third while moving. First gear, however, didn’t have any synchromesh. The designers intention was for you to only shift into low when stopped … same for reverse.

Here’s a more technical explanation via my friends at Wikipedia:

Among many different types of clutches, a dog clutch provides non-slip coupling of two rotating members. It is not at all suited to intentional slipping, in contrast with the foot-operated friction clutch of a manual-transmission car.

The gear selector does not engage or disengage the actual gear teeth which are permanently meshed. Rather, the action of the gear selector is to lock one of the freely spinning gears to the shaft that runs through its hub. The shaft then spins together with that gear. The output shaft's speed relative to the countershaft is determined by the ratio of the two gears: the one permanently attached to the countershaft, and that gear's mate which is now locked to the output shaft.

Locking the output shaft with a gear is achieved by means of a dog clutch selector. The dog clutch is a sliding selector mechanism which is splined to the output shaft, meaning that its hub has teeth that fit into slots (splines) on the shaft, forcing that shaft to rotate with it. However, the splines allow the selector to move back and forth on the shaft, which happens when it is pushed by a selector fork that is linked to the gear lever.

The fork does not rotate, so it is attached to a collar bearing on the selector. The selector is typically symmetric: it slides between two gears and has a synchromesh and teeth on each side in order to lock either gear to the shaft.

In this way two different gears can be selected. Since most automobile transmissions have more than two gears or "speeds" there are more than one selector fork. In the old-fashioned, three-speed transmissions, second and third are on one spine and shifted back and forth, typically with the aid of synchomesh, while first and reverse are on another shaft that usually lacked synchro. The shift mechanism selects between the two shift forks. One is selected when you pull back on the shifter (first and reverse) and the second when the shifter is forward (third and fourth). A locking system assures that, if one selector fork is choosing a gear, the other selector fork is held in the central position or "neutral." With the advent of four forward speeds and more, additional shift forks are usually added.

If the so-called dog teeth make contact with the gear, but the two parts are spinning at different speeds, the teeth will fail to engage and a loud grinding sound will be heard as they clatter together.

For this reason, a modern dog clutch in an automobile has a synchronizer mechanism or synchromesh, which consists of a cone clutch and blocking ring. Before the teeth can engage, the cone clutch engages first, which brings the selector and gear to the same speed using friction.

Until synchronization occurs, the teeth are prevented from making contact, because further motion of the selector is prevented by a blocker (or baulk) ring. When synchronization occurs, friction on the blocker ring is relieved and it twists slightly, bringing into alignment certain grooves or notches that allow further passage of the selector which brings the teeth together.

The exact design of the synchronizer varies among manufacturers and with the total number of gears or "speeds."

There, you are now well on your way to a degree in mechanical engineering. Next time I’ll explain planetary gears … now, back to my kid’s tale.

In those days, woe to anyone that tried to pull the shifter down into low while still moving. There were no “dog clutch” or “blocker cones” for low, and this motion would be accompanied by a terrible mechanical noise called “grinding the gears.” Anyone within earshot would shout out derisive comments on your mechanical ability such as “grind me a pound,” a reference to the preparation of hamburger in the butcher shop; or, my favorite, “they’re gonna make ‘em out of rubber next year.”

However, a true gear jockey, a title of which I was eminently entitled, could “double clutch” into low while still moving. The process was complicated and consisted of putting the shifter into neutral, releasing the clutch momentarily while revving the engine, and then push in the clutch and pull into first without any mechanical noise. What such an expert was accomplishing when releasing the clutch in neutral was to spin the gears up to exactly the speed matching the moving back wheels so that the gears would mesh without the benefit of synchro gears. Us “gear jammers” were practiced at such maneuvers and we were as proud of that ability as Liberace on the pie-an-oh was in his art.

I don’t recall when I learned this skill of “double clutching,” but I could do it for as long as I can remember, probably since I was a baby! It was a natural thing more made of muscle memory and reflexes than head knowledge, and I would often demonstrate this skill to the amazement and felicitations of my friends. And if you believe that my friends would congratulate me when I did a perfect double clutch, then you don’t know my friends very well and I’ve got a bridge in Brooklyn I’d like to sell you.

Although column shifters were the typical stock item, the long levers and mechanisms made fast shifting a bit of a clumsy act. Real racers wanted to fly from first to second to third with hardly a hesitation or loss of power to the wheels. Back then the greatest automobile modification you could make was to move the shifter from the steering column to the floor. That made the connection from lever to transmission as short as possible and allowed fast, smooth, and decisive shifting that was called for any time maximum acceleration was required.

This modification was called “four-on-the-floor,” although you usually included reverse in that count. Soon Detroit was making these shifters standard equipment in the muscle cars of the period. The best shifter of all time was made by Hurst. Some had a handle called a “tee” and it was the goal of any red blooded American boy to have a big V-8 and a Hurst shifter. Hurst is still around providing maximum shift to Mustangs, Cameros, GTOs, and even included in some hot dealer models as standard equipment.

Now days, with automatic transmissions in most cars, you only find a “stick” in either a very low cost model or in a performance automobile, however even the cheap one’s typically have four forward speeds. The shifters are now all on the floor and the meager three-speed has been replaced by an honest four-on-the-floor at a minimum, and many modern autos have five-speed trannies. My Miata has six. I have to admit that some times I forget just what gear I’m in. I long for some light on the dash to remind me I’m in fifth, not third, or sixth rather than fourth. You see, the familiar “H” is still there, but now it has extra arms. Sort of “|-|-|.”

Now first is in the upper left; down for second; up for third and down for fourth. Fifth is a push to the right and up and sixth, if you got it, is down with the same push. In all these modern cars, reverse has a special location. It may be way to the right and down, or even to the left and up. There’s a strong spring you have to overcome to get into reverse, and some have a lever you pull to unlock the backward gear. On my Miata it is a hard push to the right and down, and sometimes that doesn’t work. It helps to put the shifter in neutral and double clutch before shifting into reverse. So old habits not only die hard, but are actually quite useful still.

You see, all modern manual transmissions have synchro even on low gear, so double-clutching has become something of a lost art; sort of like putting the harness on a team of horses. Some still have the skill, but most modern men and women have lost that ability just as they’ve lost the knowledge to hunt dinosaurs with a spear.

Some people today can’t drive a stick, even with full synchro-mesh. It typically isn’t the gear pattern that’s the problem, it’s using the clutch. Especially for starting out. That’s the problem. Oh, most learn quickly, but I know a few that it just doesn’t ever come natural.

I took drivers ed. in High School. We drove a little Corvair with a manual transmission. We were taught to stop on a hill and then start out moving without any rolling backward. That was a challenge. There you were with one foot on the clutch and one on the brake, and — except for the rare circus oddity: the three legged man — most people could not run the throttle while pressing the brake and clutch pedals. I suppose “heel and toe” techniques could be applied, but we learned simpler methods. In one you would let the clutch out just enough to apply some friction and holding power from the idling engine. Then you’d quickly move the right foot from brake to gas, pressing down to rev the engine as you released the clutch further for a smooth start and no “roll-back.”

That was a tricky maneuver, but I was expert at it, and still use it on the steep hill to third avenue in Longmont. The second method requires a hand brake (sometimes called an emergency brake or a parking brake) and won’t work on those foot pedal parking brakes since the situation has already used up both feet for clutch and regular brake. If you have a hand brake you pull it out and hold the car steady so you can release the foot brake and, using gas and clutch in the regular way, as the hand brake is slowing released, up the hill you go with zero roll-back.

My dad says his old 40-something Studebaker had a "hill holder" feature that prevented backward roll. It was a great car for Seattle's steep hills. Those old cars had some neat features that are unknown by today's drivers. By the way, my dad loved Studebaker.

(Hand brakes are also useful for flipping some great “brodies” on snow covered roads when you lock up the rear wheels. That’s another skill I used to practice as a kid and admit I still use in my cul-de-sac at home. You can take the kid out of Montana, but you can’t take the Montana out of the kid — I always say.)

My old Navy buddy, Woody, had a Javelin back in the sixties made by American Motors or AMC. It was AMC's answer to the Mustang, a nice sporty two-door, but it only had a three-speed and a column shifter. The engineers had added synchro to first, so they would advertise it as a “three-and-one-half” speed.

Now those TV Babies (a term I borrowed from Donald Fagen of Steely Dan fame for anyone born after 1962) out there that never drove a car from the fifties or early sixties, don’t worry, you didn’t have to know how to double-clutch. Cars in those days had a lot of torque, which is low speed power, and you could do a lot in second gear. You really only needed first for starting from a dead stop. Actually, I could get the car going from a dead stop in second gear, but it required you ride the clutch a bit, letting it slip to keep up the rpm’s and that wasn’t good on clutches. Sort of a “these are professional drivers, don’t try this at home” procedure.

I did teach both my boys and my granddaughter to drive stick. (Linda already knew … as she’s from my generation … “I'm just talkin' 'bout my g-g-g-generation.”) As most realize when they first try, the hardest part of using the clutch is starting out without killing the engine or revving to the red line or starting with a jerking motion like some jack-in-the-box bobbing on the end of its spring. My secret is to find an empty parking lot and have the learner only use the clutch and no gas. Without worry of synchronizing the engine rpm and the clutch it is much easier to learn how to hesitate at that fine point where the clutch engages. You can start a car moving with an idling engine after a bit of practice. From there, “adding some gas” is a simple proposition. I’ve even taught a few adults how to shift for themselves using this technique, but it is clear to me that some have the natural ability, and some will always struggle a bit with the method. For them, we have “automatics,” which are also good for driving while drinking coffee and talking on the phone.

My wife is an expert shifter as she takes our pickup truck through the gears, even with its long and ungainly shifter. I don’t let her drive my sports car (although she’s snuck it out a few times), but I’m sure she would have no problem with that Mazda shifter which only moves about one-quarter of an inch in going from first to second and is apparently lubricated with butter because nothing else would be so smooth. I’m pretty sure the Miata could be shifted using only mental telepathy, it’s so easy, but I prefer doing it by hand. A little too futuristic to just think it into gear.

There is a secret to a good shift. I starts with the correct hand position. Don’t push the lever side-ways. No, just let the mechanism take the inevitable trajectory with only the slighted hint from the palm of your hand or you curved fingers when pulling down into second or fourth or sixth — all right, sixth is a little hard give a bit of a push. I used to put the old delivery truck shifter in the palm of my hand facing the windshield and just smoothly move the hand up. It would jump into second as smooth as silk. Then grasp the handle with palm down to move into third. It is all about hand position and no conscious effort required. You really do just “think it into gear.”

Some modern cars with automatics have added shifting ability, with the controls a little tab on the steering wheel. Even a little, cute “plus” and “minus” symbol to indicate direction of the shift. A little too much of the “Jetsons” for me as I’m “old school” … and simply, down-right “old.”

So that’s my story friends. I’m a gear jammer from way back. I admit the big truck I drive on Thursday for Habitat is an automatic, but I’d be at home with any lever that moves those little spinners in the gear box. Eight-speed, ten-, twelve-, it doesn’t matter. It’s in my blood, and I’d soon be zooming down the highway, double clutchin’ and talkin’ on the CB. So 10-4 good buddy, and see you on the flip side.

First gear, it's all right
Second gear, I'll lean right
Third gear, hang on tight
Faster, it's all right.

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