Suicide clutch

Suicide shifter is a common name for a motorcycle hand-shifter,^{[1][2][3][4][5]} found on early designs from around the turn of the 20th Century to the 1940s or 50s, and reappearing on modern retro styled custom motorcycles and choppers. Modern motorcycles do not require removing a hand from the handelbars to operate the clutch or to shift gears, using only the fingers for the clutch and the toes of one foot to select gears.^[6] In contrast, the fanciful slang "suicide" was applied to designs where the rider removes one hand to change gears, or cannot put both feet on the ground while using a foot clutch to disengage the transmission. Sometimes the shifter is referred to as a jockey shifter while the foot clutch is called a suicide clutch.

More technically, suicide clutch can refer to clutch controls lacking a detent on the foot clutch, which would otherwise allow the rider to lock the clutch in the disengaged position. Early foot-clutch motorcycles, such as those from Harley-Davidson and Indian, allowed the rider to lock the clutch foot pedal, so they could place both feet on the ground when stopped. If this device was disabled, or a custom foot clutch installed that had no detent, it was referred to as a "suicide clutch" because stopping the motorcycle in gear required the rider to keep his foot on the pedal. Should he lose his balance and put the left foot down, the motorcycle could lurch forward into cross traffic.

Suicide clutch

The suicide clutch is sometimes referred to as a suicide shifter. The suicide clutch is a foot-operated clutch that is mounted on the left side of the motorcycle's forward foot controls.^[7] The suicide clutch moniker has derived from difficulties in operating this form of clutch and shifter. On a motorcycle equipped with a conventional hand clutch and foot shifter, the rider places the left foot on the ground when stopped and holds the motorcycle in place with pressure on the rear brake pedal with the right foot, while engaging the clutch with the left hand. On a motorcycle equipped with a suicide clutch, the clutch is held in with the left foot, requiring the right foot to hold the bike in place, with the right hand applying pressure to the front brake.

Types of shifters

Regular clutch hand Shifter - This is where the shifter is a regular knob and involves the semi-complex task of two-handed shifting. One hand is used to press the clutch lever on the handlebars and the second hand is used to shift gears. A poorly designed motorcycle will have the clutch and a shifter on the same side making shifting annoying.

Clutched Shifter - This shifter has a clutch lever on it allowing one-handed shifting. This shifter has no advantage over the regular foot "suicide" clutch/jockey shift method, except that the rider has their left foot free.

Usage

Suicide clutches were common on mid-20th century Harley-Davidson motorcycles and many custom bikes today still employ this system. Harley-Davidson introduced the hand clutch, with uncharacteristically little fanfare, on the 1952 Panhead.^[8]

Trikes based on cars such as the Volkswagen Type 1 usually keep the original shifter.

The jockey shifter is a gear shifting device used on motorcycles before the use of a foot-operated shift lever. A jockey shifter also known as a slap shifter gets its name from the location of the motorcycle rider's hand when shifting gears, it is under his seat like the position of a jockey's hand while using his riding crop on his horse. This hand shifter lever is directly mounted to the transmission and is just long enough to clear the primary drive cover or belt drive. A motorcycle equipped with this type of shifter requires the use of a foot clutch. The foot clutch comes in one of two configurations; either a rocker foot clutch which was stock on many early motorcycles, or a suicide foot clutch which was never available on production motorcycles but was manufactured by daring motorcycle enthusiasts. The rocker foot clutch is easier to use than the suicide foot clutch because it can be rocked into a position where the clutch is either engaged or disengaged - leaving the rider's foot free to be put down, at a stop, to steady the motorcycle. Sometimes a tank shifter is referred to as a jockey shifter, but this is not technically correct due to the rider's hand position being in front of him, not behind him like for a horse jockey. The earliest known use of a foot clutch and hand shifter on motorcycles was with the first multi-geared transmission on the 1915 Harley Davidson.^[9] It is a mechanical linkage that is typically mounted to the left side of the motorbike's fuel tank and is held in place by a slotted piece of metal welded to the frame or the tank.^[7] Through a series of linkages it is connected to the transmission shift selection lever. In terms comparable to a motorcycle of current construction it is simply a way to relocate the shift lever from the front foot controls to the side of the gas tank. Early motorcycle customizers who were trying to reduce their motorcycle's weight so as to increase its power-to-weight ratio would sometimes replace their stock rocker foot clutch with a hand fabricated suicide foot clutch, and remove the tank shifter's linkage and instead attach a shifter arm directly to the transmission. This reduced weight would not only make their bike accelerate better, but they would have bragging rights of riding a motorcycle which required more skill to operate.

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