Up until a few years ago, 165mm cranks were reserved mostly for flatland riders—and actually kind of on the long side for them at that. With shorter bikes and the front and rear wheels closer together, having shorter cranks makes perfect sense for flatland. So why run 165mm cranks on a full-size BMX bike? Traditionally speaking, 165mm would typically be reserved for a shorter rider (although Dan Conway rides 165mm and he's 6' 3"). Nowadays, two of the most popular reasons are leverage and your stance. Shorter cranks have less leverage so they are less likely to bend. However, less leverage also means less torque, so it's easier to pedal, but you can't go as fast before "spinning out"—that's why racers typically run longer cranks. As for your stance, with shorter cranks you stand on your pedals with your legs closer together—which is closer to how you stand normally. Some riders feel this gives them better balance and more control for quick spins. There is also the added benefit for those riders who run a peg behind their back foot, shorter cranks helps keep their heel from hitting the peg as easily. Regardless of the reasons, 165mm cranks are gaining in popularity and today you have a number of brands to choose from.

BSD
Substance Cranks
Colors: Black, chrome
Weight: 1.95 lbs.
Lengths: 165mm, 175mm
Price: $159.99
bsdforever.com

"Single bolt design, 2.5pc cranks. Heat-treated 4130 chromoly arms with rectangular cross section for increased stiffness. Heat treated 4130 chromoly 22mm diameter CNC machined 48 spline hollow spindle. Extra beefy pedal boss with angle on the back for frame clearance. RHD/LHD compatible."

Words from Grant Smith:
“Some the team liked the shorter cranks better because of the clearance between the back of their foot and the rear pegs. Also they are a bit lighter due to the length difference. 175mm cranks are really just the standard because of racing, street riders don’t really need that length of crank.”

Fit
Indent 24 Cranks
Colors: Matte black, matte white, chrome
Weight: 30.85 oz. (175mm)
Length: 165mm, 170mm, 175mm
Price: $169.99
fitbikeco.com

"FIT 'Indent' Arms: Concaved design increases strength and dent resistance, matched to 23.80mm (24mm) hollow CrMo spindle. Works with all 15/16" center bore sprockets. RHD / LHD compatible with two sprocket bolt locations. B/B Kit included (replacement bearings also available)."

Profile
Race Cranks
Colors: tons
Length: 145mm to 190mm
Price: Varies, but $164.95 without a BB
profileracing.com 

"The Profile Racing Chrome Moly Race Crank Kit is everything you need to run Profile cranks except the bottom bracket (bearings, tube spacer and cone spacers). Kit includes crankarms, GDH heat-treated Chrome Moly spindle, crank bolts, sprocket bolt, flush washers, 6mm GDH crank bolts, and the Profile Crank Installation Tool. Titanium upgrade for the sprocket bolt is available. No Boss kit comes without a sprocket bolt. Comes with gun drilled hollow CrMo or titanium Spindle."

Premium
16 Spline Cranks
Colors: black, white, acid bath
Weight: 28.2 oz. (w/o BB)
Length: 165mm, 175mm
Price: $104.99
premiumbmx.com 

"The Premium 16-S V2 Arms/Spindle feature 4130 tubular chromoly arms with a single pinch bolt design to help keep the arms tight and ease assembly. The 19mm, 16 spline chromoly spindle is hollow and uses hollow aluminum bolts to save addition weight. RHD/LHD compatible."

Subrosa
Bitchin' Cranks
Colors: matte black, matte white, matte red, matte blue, matte army green, chrome, gun metal gray, trans orange
Weight: 30.6 oz for 175mm
Length: 165mm or 175mm
Price:  $179.99
subrosabrand.com

"Low profile, lightweight 2.5pc construction. Crank arms and spindle sold as set (bottom brackets sold separately). Seamless 4130 chromoly with post weld T5 Deathproof heat treatment. T5 Deathproof heat treated 4140 chromoly 19mm/20mm, 48 spline spindle. Includes installation/removal tool."

Wethepeople
Royal Cranks
Colors: black, raw, trans red, trans blue, chrome plate
Weight: 1.89 lbs. (crankarms, spindle, bolts), crankarm 11.14 oz. (175mm)
Length: 165mm, 170mm or 175mm
wethepeople.de

"Full seamless Japanese 4130 crmo tubing, liquid post heat-treated. 3/4" (19 mm) 4130 butted crmo spindle. Comes without BB set, but does include fitting and removal tools."

Solid
Bitch Cranks
Colors: Black, chrome
Length: 165mm, 170mm, 175mm, or 180mm
Price: $180 (arms, spindle, bolts, and shipping)
solidbmx.com

“The new Solid cranks are made in the US from US made steel and welded by Americans in America under strict US factory worker guidelines and practices while following the DIY movement founded on the principals of Minor Threat and the heart and soul of die hard riders that know exactly what the modern day rider needs and more importantly wants. The shorter cranks are stiffer and stronger than longer arms and keep your feet closer together and your toes away from the front wheel while spinning the bars.”

The Set
Stealth Crank
Colors: gloss black, clear over raw, clear, rough polish
Weight: 32.8 oz.
Length: 165mm, 170mm, 175mm, or 180mm
thesetbmx.com

"2.5 piece. Heat-treated 'rectubular' chromoly crank arms. Wraparound pedal gusset. LHD/RHD compatible. 19mm, 48-spline holloy chromoly spindle. Flush mounting and sprocket locator bolts included. Micro drive compatible. We wanted to offer more sizes in cranks as most brands only make 175mm and that's great if everyone was the exact same height and rode the exact same size bike but that's not the case so for a young smaller guy or someone on a smaller bike of fixie these are perfect ! Also When you have your feet closer together it helps you hop, try jumping without a bike with your feet apart then with your get together and note the difference. So there’s guys out there riding 175mm that should probably try some 170mm out. These cranks ain’t no joke…Super Strong & Light. And don’t worry about the holes we guarantee they will never crack from the holes!  If they ever did we’re going to give you and mate a free pair and some parts for good measure!.. But that aint gonna happen.”