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Threadless 31.8 mm 45 mm Bicycle Stems

Bar clamp diameter is the diamater of the handlebar.

Stem length is measured from the center of one clamp to the center of the other clamp. This measurement is sometimes known as the reach or extension.

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Showing 23 products:

Dimension Trail Stem - 45mm, 31.8mm, +/- 6 Degree, Aluminum, Black  Dimension Trail Stem: 45mm, 31.8, +/-6 Deg, 1-1/8", Black
Dimension Trail Stem - 45mm, 31.8mm, +/- 6 Degree, Aluminum, Black Dimension Trail Stem: 45mm, 31.8, +/-6 Deg, 1-1/8", BlackDimension

For cross country and all-mountain riding, Dimension Trail Stems provide a broad array of sizing options--lengths from 35 to 120mm--rigorously tested … read more

your price $36.99 + ships free

BuyBuyPART NUM 551340
Ritchey Trail Stem - 45 mm, 31.8 Clamp, +/-0, 1 1/8", Alloy, Black
Ritchey Trail Stem - 45 mm, 31.8 Clamp, +/-0, 1 1/8", Alloy, BlackRitchey

The Ritchey Trail Stem is the first Ritchey stem specifically designed for today's 5 to 6 inch travel trail bikes using wide bars. C220 with forward … read more

your price $44.95 + ships free

BuyBuyPART NUM 303891
Kalloy Uno Advanced Project Stem, 31.8 x 0d x 45mm Black
Kalloy Uno Advanced Project Stem, 31.8 x 0d x 45mm Black

Lightweight 3D forged 6061-T6 aluminum 4-bolt faceplate Opposing 2-bolt steerer clamp stack height = 40mm 125g (45mm) … read more

your price $16.99

BuyBuyPART NUM 775099
Origin8 Flow 3D MTB Stem, 45x31.8x28.6 0d, Black
Origin8 Flow 3D MTB Stem, 45x31.8x28.6 0d, Black

3D forged AL6061-T6 alloy construction 40mm stack height 4 bolt front loading faceplate design ISO-Mountain safety certification … read more

15% offretail $51.99 your price $44.19

BuyBuyPART NUM 200739
FSA Gradient Stem, 31.8 x 45mm, 1-1/8", Black
FSA Gradient Stem, 31.8 x 45mm, 1-1/8", BlackFull Speed Ahead

BTI Part Number: FS-4320 Vendor Part Number: 170-0009002050 Steerer Diameter: 1-1/8: Bar Diameter: 31.8 Rise: … read more

your price $74.00 + ships free

BuyBuyPART NUM 647506
Origin8 Flux MTB Stem 1 1/8" x 31.8mm clamp  45mm 0 degree
Origin8 Flux MTB Stem 1 1/8" x 31.8mm clamp 45mm 0 degree

Full CNC machined AL6061-T6 alloy construction 35mm stack height 4 bolt front loading faceplate design ISO-Mountain safety certification … read more

your price $84.99 + ships free

BuyBuyPART NUM 297238
Ritchey WCS Trail Stem: 45mm, +/- 0, 31.8, 1-1/8, Blatte
Ritchey WCS Trail Stem: 45mm, +/- 0, 31.8, 1-1/8, BlatteRitchey

Ritchey Stems 3D Forged 2014 alloy C220 with forward facing bolt design for easy installation 220 degree, extra-wide bar clamp improves … read more

your price $89.95 + ships free

BuyBuyPART NUM 383693
Chromag Riza Stem, 45 x 28.6, 90 Degree, Gold
Chromag Riza Stem, 45 x 28.6, 90 Degree, Gold

M6 bolts Wide clamping area spreads load over large area 1 piece faceplate CNC machined in Whistler, Canada Faded edges … read more

your price $135.00 + ships free

BuyBuyPART NUM 601824
Chromag RIZA Stem, (31.8) 90d X 45mm - Silver
Chromag RIZA Stem, (31.8) 90d X 45mm - Silver

CNC machined in Whistler, Canada from premium 6061 billet aluminum Features a new faded edge on the clamp face to help avoid hot spots and … read more

your price $135.00 + ships free

BuyBuyPART NUM 599714
EVO, Caliber, Stem, Diameter: 31.8mm, Length: 45mm, Steerer: 28.6mm, 0 degree, Black
EVO, Caliber, Stem, Diameter: 31.8mm, Length: 45mm, Steerer: 28.6mm, 0 degree, Black

3D forged alloy construction Fits 1-1/8 (28.6mm) steerer forks Fits 31.8mm handlebar clamp Heat treated hardware Item … read more

your price $39.99 + ships free

BuyBuyPART NUM 721298
Chromag RIZA Stem, (31.8) 90d X 45mm - Red
Chromag RIZA Stem, (31.8) 90d X 45mm - Red

CNC machined in Whistler, Canada from premium 6061 billet aluminum Features a new faded edge on the clamp face to help avoid hot spots and … read more

$13 offretail $135.00 your price $121.50 + ships free

BuyBuyPART NUM 262128
Chromag Riza Stem, 45 x 28.6, 90 Degree, Blue
Chromag Riza Stem, 45 x 28.6, 90 Degree, Blue

M6 bolts Wide clamping area spreads load over large area 1 piece faceplate CNC machined in Whistler, Canada Faded edges … read more

$13 offretail $135.00 your price $121.50 + ships free

BuyBuyPART NUM 674993
Chromag Riza Stem, 45 x 28.6, 90 Degree, Black
Chromag Riza Stem, 45 x 28.6, 90 Degree, Black

M6 bolts Wide clamping area spreads load over large area 1 piece faceplate CNC machined in Whistler, Canada Faded edges … read more

$13 offretail $135.00 your price $121.50 + ships free

BuyBuyPART NUM 170652
Promax Gryf 31.8mm MTB Stem, Length 45mm, 1-1/8" Threadless Black
Promax Gryf 31.8mm MTB Stem, Length 45mm, 1-1/8" Threadless Black

Promax Gryf Stems. Rugged, durable, dependable. The GRYF stem was designed and cold forged to hold up on any ride. City, trail, mountain. Item Specifications … read more

your price $44.99 + ships free

BuyBuyPART NUM 960766
Ritchey Comp Trail Stem (35) 0dx45, Black
Ritchey Comp Trail Stem (35) 0dx45, BlackRitchey

Extra-wide 41mm wide bar clamp improves stiffness and fits most riser bars 3D forged 6061 alloy 42mm steerer height 142g (90mm) … read more

your price $59.95 + ships free

BuyBuyPART NUM 881290
Thomson X4 1.5" 45mm 0 Degrees 31.8 Black
Thomson X4 1.5" 45mm 0 Degrees 31.8 BlackThomson

Thomson X4 One Point Five Stems feature custom heat-treated bolts with corrosion-preventative plating. Machined 7000-series extruded bar … read more

Currently Sold Out

your price $114.95 + ships free

InfoInfo
Tag Metals T1 Stem, 31.8 x 45mm, Black
Tag Metals T1 Stem, 31.8 x 45mm, Black

CNC machined 2014 aluminum body with 4-bolt bar clamp TAG speed adjust bar markings for quick and easy set up 166-222g including bolts … read more

Currently Sold Out

$35 offretail $109.99 your price $74.99 + ships free

InfoInfo
Spank SPLIT 35  Stem - 45mm, 35mm Clamp, 0 Degree, 1-1/8", Green Metal
Spank SPLIT 35 Stem - 45mm, 35mm Clamp, 0 Degree, 1-1/8", Green Metal

Highly weight optimized single crown stem, ideal for Enduro applications with 31.8mm handlebars Human Factor Design features micro increment size options … read more

Currently Sold Out

your price $99.99 + ships free

InfoInfo
NS Bikes Quantum Lite Stem, 31.8 x 45mm, 0 Degrees, Black
NS Bikes Quantum Lite Stem, 31.8 x 45mm, 0 Degrees, Black

Lightweight, cold forged, CNC machined 6061-T6 aluminum Knee friendly steerer tube clamp design with 5mm tapered-head bolts. 140g Item … read more

Currently Sold Out

your price $84.99 + ships free

InfoInfo
Octane One Tone Stem, 31.8mm x 45mm, Blue
Octane One Tone Stem, 31.8mm x 45mm, Blue

3D forged 6061 aluminum, perfect for All Mountain and Trail riding 40mm steerer clamp height 138g (31.8mm) Item Specifications … read more

Currently Sold Out

your price $31.99

InfoInfo
Dimension

Dimension makes quality components to repair or custom-fit the vast majority of bikes being ridden today, and provide the accessories that make them fun to ride.

See all Dimension

Ritchey

"Ritchey bicycle components have been raced to victory in some of the biggest cycling competitions in the world including the UCI World Championships, the Tour de France and the Olympics and it all began in a simple garage in Menlo Park, California with Tom Ritchey.'

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Full Speed Ahead

"We move forward with a desire to deliver the best possible components to our customers and a determined spirit of competition."

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Thomson

Thomson is leading with innovative design for two primary markets - aerospace and cycling.

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We define color as the main color of the item. It may have accents or highlights in other colors.

These models are available for online purchasing and can be shipped directly to you.

Bar clamp diameter is the diamater of the handlebar.

Stem length is measured from the center of one clamp to the center of the other clamp. This measurement is sometimes known as the reach or extension.

S.H.I.S clamp diameter is the steerer tube diameter.

Stem angles are measured perpendicular to the clamp. For example, a 90 degree stem is straight. Sometimes, this may also be refered to as a 0 degree stem. If two measurements are listed, the stem can be flipped for angling up or down.

Stem Type

This is the part number or identifier for this item from the manufacturer

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