Category: BMX Parts Info
18Jul

In this post we will discuss the specs and features of most aftermarket BMX Handlebars.
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Rise
The Rise, or Height of the Handlebars will be measured in inches from the bottom of the knurled clamping surface to the top of the grip surface.
Most modern Handlebars are offered in sizes varying from 8.25″ up to 10″+.
Generally speaking, the shorter the Handlebars, the more room you have to pull the front wheel off the ground, therefore making it essier to hop higher.
However, taller bars have been proven to help posture while riding, which can make a major difference for those that experience back pains/cramps from riding.
Using this information, it is important to pinpoint your “sweet spot” for maximum comfort without minimizing your hop height. Everyone’s sweet spot is different, especially for those with back problems that need a little extra rise, however these are some fair recommendations for Handlebar Rise based on rider height.
5’5″- : 8.25 – 8.5″
5’6″ – 5’10” : 8.5 – 9″
5’11” – 6’2″ : 9 – 9.5″
6’4″+ : 9.5 – 10.5″

Width
The Width of the Handlebars is the distance from bar-end to bar-end measured in inches. 
Most handlebars come in options from 27″ up to 30″+, however any set of handlebars can easily be cut to your width preference with a pipe cutter or a sawzall/other power saw (so don’t worry if your favorite handlebars are wider than you’d like.)
Generally speaking, the ideal Handlebar Width for BMX is the rider’s shoulder width, or close to it, because this provides the most efficient use of your arms when pulling up to hop (try doing a push-up with your hands at shoulder width, and another with them spread out past your shoulders, you will notice that you lose efficiency of your muscles when half your force is being exerted outwards instead of straight up & down.)
Trick-wise, narrower Handlebars make bar spins much easier, while wider Handlebars make turn downs easier to click.

Upsweep
The Upsweep of the Handlebars is the upwards angle of the grip-section, and most Handlebars are available with anywhere from 1 to 5 degrees of Upsweep.
This is a tricky spec, due to everyones’ wrists being slightly different & how Handlebar Width affects it.
What the Upsweep does is create a level contact surface for your hand on your grips, so you can properly absorb impact into your arms while minimizing any harm to your wrists from doing so.
Examples; If you are not riding enough Upsweep, you may notice pain/uncomfort in your inner wrist. & if you are riding too much Upsweep, you may notice pain/uncomfort in your outer wrist.
The “perfect” amount of Upsweep will allow both your inner and outer wrist to be in contact with the grip simultaneously, providing maximum comfort.
And with all that said, the wider you hold your hands apart, the more you increase the angle of your wrists, thus needing more Upsweep to compensate & vice versa (so if you plan on changing your Handlebar Width on your next set, you may want to consider a slight difference in Upsweep to compensate.)

Backsweep
The Backsweep of the Handlebars is the backwards angle of the grip-section. Most handlebars will be available with anywhere from 9 to 12 degrees of Backsweep.
Quite similar to Upsweep, Backsweep is to ensure a proper hand-on-grip contact for comfort & proper impact absorption into the wrists. This spec is also entirely dependent on the rider’s wrist angle, how wide they hold their hands apart, etc.

Heat Treatment
A lot of aftermarket Handlebars are Heat Treated, which means the tubes have been heated and cooled in a way that strengthens them. 
The first and cheaper method is to use heat treated tubes to build the Handlebars. However, the heat of welding can negate the treatment of the tube near the weld, which brings me to method #2..
Post-weld Heat Treatment is a process that consists of heat treating the Handlebars post-production so that the properties of the metal are the same through out the welds. This is the most efficient way to strengthen both the tubes and the welds.

2 Piece vs. 4 Piece
2 Piece (2pc) & 4 Piece (4pc) both refer to the amount of tubes used to build the Handlebars. This does not necessarily effect the strength or function of the handlebars, and is entirely aesthetic. 
2pc Handlebars usually are built by bending a long tube into what will be both the grip-sections & the knurled clamping area, with a second, shorter tube used as the Crossbar.
4pc Handlebars generally use two separate tubes for the grip-sections, along with two Crossbars, one of which has the knurled clamping area.

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With all of this information taken into consideration, you should be ready to pick out your own new BMX Handlebars! 

Info taken from: https://www.vitalbmx.com/forums/General-BMX-Talk,2/BMX-Handlebar-Buying-Guide,1319933#edit_post_2302697
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18Jul

2, 2.5, 3 Piece
This spec refers to the amount of Pieces required to assemble the Cranks.
3pc (2x Crank Arms & 1x Spindle) is the Industry Standard, and 2 / 2.5 are functionally the same.
2pc feature the 3pc design, but with one of the Crank Arms welded on to the Spindle.
2.5pc is similar to 2pc, except the Crank Arm can be removed from the other side of the Spindle.
All 3 of the options above are drilled for 9/16″ Pedals.
Avoid 1-pc Cranks at all costs. They are significantly weaker and do not fit most modern Bottom Brackets.

Spindle Diameter (19, 22, & 24mm)
The Spindle Diameter is the thickness of the Cranks’ “axle” that runs through the Bottom Bracket of the Frame. This spec is solely personal preference, and doesn’t effect how the bike maneuvers. Sizes include 19mm, 22mm, and 24mm (15/16″.)
Generally speaking, larger spindles are stiffer & lighter, without sacrificing strength in the Cranks. However, with a larger spindle means smaller bearings, which are more prone to blowing out.
(WARNING: I do not recommend running Spline-Drive [SD] Sprockets with 22mm or 24mm set ups, as there is different styles of splines that effect whether or not the cranks and sprocket are compatible. The chances of you getting an appropriate SD Sprocket for your cranks, without prior knowledge, is slim.)

Crank Arm Length (160-180mm)
The Crank Arm Length is the measurement regarding the distance from the Spindle Boss to the Pedal Boss. This does effect how the bike handles. Sizes for 20″+ BMX Bikes range from 160mm to 180mm.
The shorter your Crank Arms are, the easier spin tricks will be since your feet are closer together. Having shorter arms also clears a bit of room for your feet, so you’re not as likely to hit your heel on your rear peg. Shorter cranks are known to also feel stiffer than their longer counterparts. 
The longer your Crank Arms are, the easier it will be to pedal, as you have more leverage over your Drive Train. They are also renound for making the bike feel more stable, and less twitchy.

Spindle Interface
The Spindle Interface is the way the Crank Arm(s) connect to the Spindle. This can range from 6-Spline to 48-Spline set ups, to even Splineless Interfaces, such as Primo’s square-shaped Spindle & Odyssey’s patented Socket Interface (nonagon-shaped Spindle.)
As far as buying aftermarket Cranks goes, you will want to avoid 6 / 8 / 10 / 16 Spline set ups. They are generally cheaply made and are prone to failing at the split Spindle Boss.
Majority of quality aftermarket Cranks are 48-Spline. They allow for the Crank Arms to fit snug on the Spindle without the help of any unnecessary bolts or a split Spindle Boss. This is your best option for Splined Cranks.
There is also a few different Splineless options. #1 being Odyssey’s patented Socket Interface, which features a wedge system that is guaranteed to stay snug on the Spindle and never wear itself loose. You cannot run Spline Drive with Splineless Cranks.

Tubular / Square-shaped Crank Arms
This is another feature that doesn’t effect how the bike rides & is solely rider preference. 
Most people are fine with a simple Tubular Crankset, meaning the Crank Arms are round in shape.
However, a lot of riders who do Crank Arm Grinds prefer Square-shaped Crank Arms for their flat surface that is optimal for locking into grinds.

Bolt-Drive or Bossless
These are two different styles of Cranks for different Sprocket compatibility.
Bolt-Drive Cranks are the most common kind of Cranks, with a boss for a Sprocket Bolt located on the back of the Crank Arm(s). You can also run Spline Drive on Bolt-Drive Cranks, so long as they are 48-Spline.
Some companies also utilize the Bossless design, meaning there is no Sprocket Bolt Boss on the Crank Arms, limiting you to Spline Drive/Socket Drive Sprockets. Some riders opt for Bossless Cranks for the weight savings & clean look.

Heat Treatment
A lot of quality aftermarket Cranks are Heat Treated, which means the tubes have been heated and cooled in a way that strengthens them. 
The first and cheaper method is to use heat treated tubes to build the cranks. However, the heat of welding can negate the treatment of the tube near the weld, which brings me to method #2..
Post-weld Heat Treatment is a process that consists of heat treating the Cranks post-production so that the properties of the metal are the same through out the welds. This is the most efficient way to strengthen both the tubes and the welds. 

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With all of this information & your own preference taken into consideration, you should be ready to pick out your own new BMX Cranks!

Info taken from: https://www.vitalbmx.com/forums/General-BMX-Talk,2/BMX-Crank-Buying-Guide,1318289

18Jul

In this post, we’re going to go over all the different specifications & features of modern freestyle frames. 
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These are all important specs to consider when purchasing a new BMX frame. The specs, or specifications, are the geometric measurements of the frame that give it it’s own unique feel.

Top Tube (TT) Length
This is the first and most important spec to take in to consideration when it comes time to pick your new frame. It is the length between the frame’s Seat Tube and its Head Tube, and it is used generally to describe the size of a frame. Most modern 20″ frames come in actual sizes between 20.25″ & 21.75″. Typically you will choose a size based on your own height, but personal preference also comes into play. A slightly longer top tube will be more stable & comfortable, but harder to manipulate for some tricks. A slightly shorter top tube will be less roomy & stable, but can make a lot of tricks simpler. Here is a list of estimated frame sizes based off of height. Using the this plus the information above will help you decide on an appropriate frame size for yourself. 
5’1″ – 5’3″ / 20.25″
5’4″ – 5’6″ / 20.5″
5’7″ – 5’9″ / 20.75″
5’10” – 6’0″ / 21″
6’1″-6’3″ / 21.25″
6’4″ – 6’6″ / 21.5
6’7″+ / 21.6 – 22″

Chainstay (CS) Length
This is the length between the Bottom Bracket and the frame’s Drop Outs. They generally span from 12.7″ to 14.5″. This spec is solely based on personal preference. 
The shorter the Chain Stays, the easier it is to manipulate the bike for tricks. They also make it easier to get up on the rear wheel for manuals and such, but at the same time makes it harder to “lock in” and balance it. Shorter chain stays also make for a twitchier bike.
The longer the chain stays, the harder it is to initiate manuals and rear wheel tricks, but the easier it is to lock in and balance them. Longer chainstays will make for a stable tail end of the bike. 

Head Tube Angle (HTA)
This is the angle of the Head Tube, which is relevant to steering, stability, and front wheel tricks. The Head Tube Angle will usually range from 74 degrees (mellow) to 76 degrees (steep.)
The steeper the head tube, the more responsive your steering will be, and the easier it will be to initiate front wheel tricks like nose manuals.
The mellower the head tube, the more stable your front end will be, aswell as it will be easier to lock in and balance front wheel tricks.

Bottom Bracket Height (BBH)
This is the height of the Bottom Bracket. It will usually range from 11.5″ to 11.8″. 
Lower bottom brackets are renound for bringing a super stable feel to the bike, aswell as making it easier to balance manuals and other rear wheel tricks.
Higher bottom brackets make for a more “poppy” feel in the bike, especially when hopping and doing tricks. They make it easier to initiate rear end tricks, but harder to lock into them.
Also keep in mind that when you change your BBH, it changes the distance between your feet and your handlebars. Lowering your Bottom Bracket by .25″ will make your bars feel .25″ taller.

Stand Over Height (SOH)
This is the length of the Seat Tube. This will usually range anywhere from 7″ to 10″. The taller you go, the harder it becomes to do tricks such as can-cans or tailwhips, as the Top Tube is now that much higher and more in the way. Taller Stand Overs are also said to make for a stiffer, stronger frame. This spec is pretty dependant on personal preference and riding style. 

Seat Tube Angle (STA)
This would be the angle of the Seat Tube. This alters the effective feel of the Top Tube, in correspondence to the Stand Over Height. The industry standard for STA’s is 71-degrees, but can range from 69-degrees to 72-degrees. 
Basically, when you change the STA, you have to add or remove some Top Tube material, without altering the position of the Bottom Bracket. And the taller the SOH, the larger the difference. 
Example: A 21″ TT frame with a 9″ SOH and 71-degree STA will ride identical to a 21.3″ TT frame with a 9″ SOH and 69-degree STA (assuming all other specs are the same aswell.)
This is because the difference between the 71-deg and 69-deg on a 9″ SOH is 0.31″, meaning you have an extra .31″ of top tube but your Bottom Bracket is still the same distance from the Head Tube. 

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Now that you’ve figured out what specs should suit your body and riding style, you are ready to choose a frame based off of its features. The features of the frame are the technical specifications that decide its structural integrity and its weight.

Heat Treatment
Most aftermarket frames are Heat Treated, which means the tubes have been heated and cooled in a way that strengthens them. There are two different ways a frame will be treated. 
The first and cheaper method is to use heat treated tubes to build the frame. However, the heat of welding can alter the heat treated properties of the tube near the weld, which brings me to method #2.
Post-weld Heat Treatment is a process that consists of heat treating the entire frame post-production so that the properties of the metal are the same through out the weld. This is the most efficient way to strengthen both the tubes and the welds. 

Investment Casting
Investment Casting in BMX is essentially a way to move a weld away from a joint for a stronger or larger connection. It is done by casting pieces of the frame, such as a Head Tube or Drop Outs, with segments of the corresponding tube built in to it. This usually, but not always, makes for a more durable section of the frame. 

Ovalized Tubing 
Some frames will use Ovalized Tubing for the Down Tube and the Chain Stays. Due to the shape of the tube, they are much less likely to dent or bend on the bottom of the tube. This is preferable for riders who hit their their frame in those spots on grinds and such.

Wave Tubing
This option is only available from Sunday Bikes. Similar to Ovalized Tubing, they make the tube dent proof by adding “waves” to the bottom of the tube. This feature is limited to a few of their frames. 

Tapered Tubing
Some companies will use Tapered Tubing to save weight without a significant difference in strength. A tapered tube is one that is slightly narrower in diameter on one end than it is on the other.

Butted Tubing
Butted Tubes are tubes that are thicker on the ends than in the center. This can be done for two very different reasons.
The first being that you can essentially beef up the end of the tube for a stronger weld with very little difference in weight compared to a straight gauge tube.
The second method is to remove material from the center of ideally a straight gauge tube, making a lighter tube without sacrificing strength from the weld.

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Info taken from: https://www.vitalbmx.com/forums/General-BMX-Talk,2/BMX-Frame-Buying-Guide,1317923#edit_post_2273371

18Jul

In this post we will discuss the specs and features of most aftermarket BMX Forks. 

Offset
The Offset of the Fork is the distance from the center of the fork leg to the beginning of the axle slot in the drop out. This effects stability, steering, & front wheel tricks noticeably. 
The shorter the offset, the easier it will be to initiate front wheel tricks like nose manuals or footjams. You will also notice your steering is more responsive with shorter offset forks.
The longer the offset, the easier it will be to balance front wheel tricks & the more stable your front end will feel.
Here’s a list of general recommendations for different types of riding, though it truly comes down to personal preference. 
Flatland / Streetland : 0mm – 15mm
Street / Park : 15mm – 32mm
Trails / High Air : 25mm – 35mm

Height
The Fork Height is the vertical distance between the Wheel Base & the top of the Fork Crown. This is a pretty general spec that can noticeably change the feel of your bike.
Majority of aftermarket BMX forks are 315mm in height, which is the industry standard. However, some companies, such as S&M and WTP offer 320mm & 310mm forks.
The taller you go, the more mellow your Head Tube will feel, and your Bottom Bracket may even feel slightly taller.
The shorter you go, the steeper your Head Tube will feel, and the lower your Bottom Bracket may feel. 
Fork Height is irrelevant to Offset or Tire Clearance.

Steerer Tube Length
This is the length of the Steerer Tube, or the tube that goes into the Frame & Stem of the bike. This is another general spec to take into consideration, depending on your frame and personal preference. 
This mainly effects how high you can run your stem, & also what frame(s) the forks are compatible with.
The industry standard for Steerer Tube Length is around 160-166mm. This is ideal for frames with an average Head Tube Height.
S&M and other companies are now offering XL Steerer Tubes, which are around 170-175mm in height. These are necessary for some frames with extra tall Head Tubes. They also make a nice option for those looking to raise their stem on their bike. 

Compression Bolt
This is the bolt that holds down the stem on the steerer tube. Most high quality forks come with H24 or H25 bolts and an internally threaded steerer tube. I would avoid any forks with a welded/star nut, as they can be more likely to fail. 
Note that H25 forks have a reputation for breaking inside the stem due to the steerer tube having to be so thin. H24 is the way to go.

Heat Treatment
A lot of aftermarket forks are Heat Treated, which means the tubes have been heated and cooled in a way that strengthens them. 
The first and cheaper method is to use heat treated tubes to build the forks. However, the heat of welding can negate the treatment of the tube near the weld, which brings me to method #2..
Post-weld Heat Treatment is a process that consists of heat treating the forks post-production so that the properties of the metal are the same through out the welds. This is the most efficient way to strengthen both the tubes and the welds. 

Investment Cast Drop Outs
Investment Cast Drop Outs are drop outs that have been made in a cast with sections of the Fork legs. This makes for a bigger & more efficiently placed weld.

Integrated Bearing Race
Most high end Forks will come with an Integrated Bearing Race built into the crown/steerer tube junction. The integrated race is just a small lip that eliminates the need for a cheap, removable race.

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With all of this information taken into consideration, you should be ready to pick out your own new BMX Forks! 

Info Taken from: https://www.vitalbmx.com/forums/General-BMX-Talk,2/BMX-Fork-Buying-Guide,1317982