stem

In music notation, a stem is the vertical line drawn next to the note-head on certain notes. The stem begins at the note head and is drawn straight up or straight down, depending on whether the note is in the bottom or top half of the staff. All notes of shorter duration than a whole note use a stem, including the half note, the quarter note, and the eighth note.

For a threaded headset, the stem is an upside-down "L" shaped piece of metal. The downward pointing piece is inserted into the steerer tube and is held there by a wedge-shaped quill that is pulled up tight using a long bolt running the length of the stem. The other section of the stem points forward and attaches to the handlebar via some sort of a clamp. The exact angle of the stem varies between bicycles. On most road bikes, the stem will angle down; the point of attachment for the handlebar is actually below the bend in the stem. Stems for mountain bikes, however, generally angle up a fair bit.
The height of this type of stem can be easily adjusted. Simply loosen the bolt on top of it which runs into the steerer tube, and give it a tap with a hammer. This dislodges the quill inside the steerer tube. Then adjust the height, and after making sure it is centered over front wheel, retighten the bolt. The bolt should be relatively snug, but take care not to overtighten it, as this will only damage the inside of the steerer tube.

Stems for threadless headsets are a much more simple design. On this type of a headset, the steerer tube actuall protrudes above the head tube of the bike. The stem is essentially a piece of tubing with clamps at both ends. One clamp attaches to this piece of the steerer tube, the other to the handlebar. The stem is actually responsible for holding the fork in the bike. This can be a much more sturdy design, and is used on most mountain bikes. Very little changes can be made to the height of this type of stem, however. At best, one can place a few spacers between the stem and the headset, raising it slightly.

Angle and length of the stem are one of many factors that significantly influence the ride of a bike. Longer stems with a very shallow angle will put the rider further forward over the bike. This is very good for aerodynamics and hill climbing. An extreme form of this is seen on road bikes. Shorter, steeper stems, especially when coupled with a riser bar, will make for a tighter cockpit on a mountain bike, increasing mobility. This is very handy on more technical trails.

Stem (?), Steem (?), v. i.

To gleam.

His head bald, that shone as any glass, . . . [And] stemed as a furnace of a leed [caldron]. Chaucer.

© Webster 1913.

Stem, Steem, n.

A gleam of light; flame.

© Webster 1913.

Stem (?), n. [AS. stemn, stefn, staefn; akin to OS. stamn the stem of a ship, D. stam stem, steven stem of a ship, G. stamm stem, steven stem of a ship, Icel. stafn, stamn, stem of a ship, stofn, stomn, stem, Sw. stam a tree trunk, Dan. stamme. Cf. Staff, Stand.]

1.

The principal body of a tree, shrub, or plant, of any kind; the main stock; the part which supports the branches or the head or top.

After they are shot up thirty feet in length, they spread a very large top, having no bough nor twig in the trunk or the stem. Sir W. Raleigh.

The lowering spring, with lavish rain, Beats down the slender stem and breaded grain. Dryden.

2.

A little branch which connects a fruit, flower, or leaf with a main branch; a peduncle, pedicel, or petiole; as, the stem of an apple or a cherry.

3.

The stock of a family; a race or generation of progenitors.

Milton.

While I do pray, learn here thy stem And true descent. Herbert.

4.

A branch of a family.

This is a stem Of that victorious stock. Shak.

5. Naut.

A curved piece of timber to which the two sides of a ship are united at the fore end. The lower end of it is scarfed to the keel, and the bowsprit rests upon its upper end. Hence, the forward part of a vessel; the bow.

6.

Fig.: An advanced or leading position; the lookout.

Wolsey sat at the stem more than twenty years. Fuller.

7.

Anything resembling a stem or stalk; as, the stem of a tobacco pipe; the stem of a watch case, or that part to which the ring, by which it is suspended, is attached.

8. Bot.

That part of a plant which bears leaves, or rudiments of leaves, whether rising above ground or wholly subterranean.

9. Zool. (a)

The entire central axis of a feather.

The basal portion of the body of one of the Pennatulacea, or of a gorgonian.

10. Mus.

The short perpendicular line added to the body of a note; the tail of a crotchet, quaver, semiquaver, etc.

11. Gram.

The part of an inflected word which remains unchanged (except by euphonic variations) throughout a given inflection; theme; base.

From stem to stern Naut., from one end of the ship to the other, or through the whole length. -- Stem leaf Bot., a leaf growing from the stem of a plant, as contrasted with a basal or radical leaf.

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Stem, v. t.

1.

To remove the stem or stems from; as, to stem cherries; to remove the stem and its appendages (ribs and veins) from; as, to stem tobacco leaves.

2.

To ram, as clay, into a blasting hole.

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Stem, v. t. [imp. & p. p. Stemmed (?); p. pr. & vb. n. Stemming.] [Either from stem, n., or akin to stammer; cf. G. stemmen to press against.]

To oppose or cut with, or as with, the stem of a vessel; to resist, or make progress against; to stop or check the flow of, as a current.

Shak.

[They] stem the flood with their erected breasts. Denham.

Stemmed the wild torrent of a barbarous age. Pope.

© Webster 1913.

Stem, v. i.

To move forward against an obstacle, as a vessel against a current.

Stemming nightly toward the pole. Milton.

© Webster 1913.