Rims

How to choose BMX rims: With so many options available when choosing a rim, it can be difficult to pick a version that suits your style of riding. Choosing a rim that is not strong enough for your style of riding can result in constant maintenance on your wheels, which can be frustrating. The same can be said for a wheel that is overbuilt, adding unneeded material and rotational weight that can cause a bike to feel sluggish when ridden. This article will outline the common rim material and design differences.

Materials

Before buying, be sure to do your research and read product reviews. Reviews are a great way to find out specifics about a particular model, user impressions, and things to watch out for. After you’ve purchased a product and had enough time to thoroughly test it, we encourage you to leave a review for other people to see when they are researching bikes and parts on the web.

Wall Structure

When looking at a rim from the outside it may appear that all companies use a similar, simple design. However, what you can’t see is the internal wall structure that forms several hollow chambers inside the rim. These would be visible if you were to cut the rim in half, as shown in this diagram.

Generally the number of walls will reflect the rim’s strength. A single walled rim will not provide the same structural support as a double or triple walled rim. However, the increased material used to construct the additional walls adds weight. Because of this, triple walled rims are often overkill for a rider unless they put a huge amount of stress on their wheels. Double walled rims usually give the best strength to weight ratio, and because of this they are the most commonly used version.

Geometry

When looking at rim specifications, you’ll likely see the following two terms:

Rim Width – Rim width descries the width of the rim, from one outer wall to the other.

Rim Height – Rim height is the height of the rim’s wall. It is easy to confuse the rim’s height with wheel size. All BMX wheels use a 20” diameter wheel size.

Spoke Holes – The number of spoke holes in a hub does not affect the structural integrity of the hub, but it is a factor in the construction and strength of a complete wheel. Refer to the Wheel Buyer’s Guide Article for more info.

Pinned vs. Welded

Rims are constructed by bending a piece of aluminum into a circle, then attaching the ends of the loop together at the “seam.”

Welded seams are the strongest option, and are generally used in more expensive, higher-end rims.

Pinned rims use a small piece of metal to hold each end of the rim together at the seam. The issue with pinned rims is that a strong impact to the wheel (casing a jump for example) can knock the pin loose allowing the seam of the rim to separate. Because of this, pinned rims are generally the weaker variation, and are often used on lower end completes and wheelsets.

How Much To Spend

It’s always important to remember the saying, “you get what you pay for” when purchasing new bike parts. When you spend more, you are paying for higher quality materials and better construction. This rule applies to the quality of rims. When you spend more on a rim, you are buying higher quality alloys combined with special wall structures.

When purchasing a rim, you should be looking to spend between $30 and $90. The $30-$60 range will use slightly heavier alloys, a single or double walled rim thickness, and pinned or welded seams. The $60-$90 range will offer the best strength to weight ratio, material quality, design, and manufacturing process.

What To Look For

When purchasing new rims, the first thing that should be considered is your style of riding and how much force you exert on your wheels. If you are a lighter rider or a racer, you will be able to run single walled, lighter alloy wheels without major issues. However, if you are riding dirt, park, or street, you will want a rim that can take the physical stress of spinning, jumping and dropping.

Rim Height can also be an important factor to consider. The rim height and shape will affect the wheel’s braking surface. If you run brakes, a rim with shorter or curved wall may not work as well as a rim with a tall flat wall.

Because wheels are expensive and can take a lot of effort to build and maintain, you want your wheels to last, so picking a rim that will be able to withstand your riding is crucial.

Product Reviews

Before buying, be sure to do your research and read product reviews. Reviews are a great way to find out specifics about a particular model, user impressions, and things to watch out for. After you’ve purchased a product and had enough time to thoroughly test it, we encourage you to leave a review for other people to see when they are researching bikes and parts on the web.

We hope you’ve found this information to be helpful. If you have a question that isn’t answered in this guide, our BMX forums are a great place to get advice from knowledgeable riders. Your local bike shop is also a great resource.

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