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For many years, protecting carbon steel from corrosion typically involved either the use of hot-dip galvanizing (HDG)* or some type of paint or powder coating system*. However, more and more corrosion specialists are utilizing both methods of corrosion protection in what is commonly referred to as a duplex system or duplex finish: simply painting or powder coating steel that has been hot-dip galvanized.

Triple B is the leading company bringing the benefits of Duplex Finish to motorcycle enthusiasts, giving access to next generation corrosion protection.

Note: If you are wondering why we use Carbon Steel instead of Stainless Steel please click here!

According to the American Galvanizers Association, Duplex Finish corrosion protection is superior to either protection system used alone and can last from 1.5 to 2.3 times the combined lifetimes of both systems:

The synergistic effect of using two coatings extends the service life for unparalleled corrosion protection, while the metallurgically-bonded galvanized coating serves as an ideal primer to provide an impervious barrier for the base steel. When paint and galvanized steel are used together, the corrosion protection is superior to either protection system used alone and can last from 1.5 to 2.3 times the combined lifetimes of both systems. In other words, if you had a paint system that lasts 10 years and a hot-dip galvanized system expected to last 70 years, the duplex system would last 120 – 200 years –if you just let the paint and galvanizing wear away naturally.

Duplex Systems: Paint or Powder Coating over HDG – Galvanizeit.org – American Galvanizers Association *

The superiority of Duplex Finish in more detail:

Until now, steel parts used in the motorcycle industry are either galvanized or powder coated but not both.

Hot-dip galvanization is basically the process of coating iron and steel with zinc.  When done correctly (i.e. according to the ASTM standards), the zinc layer provides cathodic and barrier protection, preventing the steel from oxidizing, resulting in a longer part life.

However, the finish of the hot-dip galvanized steel is silvery-grey and as it naturally oxidizes it will turn dull grey. Even the brightest hot dip galvanized finish loses its shine in a short period of time and turns dull.

Galvanized coatings can also take on a number of different appearances, mainly due to the steel chemistry, which are not under the galvanizer’s control. The corrosion protection is the same, but the appearance differs. The differences will become uniform over time as the material weathers naturally.  But as you can imagine, the different appearances for the same product line can be challenging for manufacturers like ourselves, mainly due to the lack of uniform finish.   

Another issue with the hot-dip galvanized steel is surface imperfections. Due to the nature of the Hot Dip Galvanization (HDG) process, surface imperfections such as excess zinc formed on the surface of the steel, high spots or pits may exist on parts. Such minor imperfections on Hot Dip Galvanized parts may not be considered as manufacturing defects, but this does not change the fact that the surface finish is far from aesthetically pleasing. If you look close enough at the surface of the hot-dip galvanized steel you’ll notice that it resembles the surface of the moon.

So due to the dull finish, variance in appearances, and surface imperfections many manufacturers and designers prefer powder coated steel over hot-dip galvanized steel. Also in general the initial cost of powder coating process is cheaper than hot-dip galvanizing.

However, the biggest issue with powder coating or painting bare steel as the only barrier against corrosion in moving parts (i.e. drop and drag links of the rear suspension system of a motorcycle) is that the powder coating or paint under the fasteners won’t last long. This happens because, in a moving part like suspension drop or drag link fixed with nuts and bolts, the fasteners scrape the paint, exposing the bare steel underneath. Since there is no protecting layer anymore, the exposed metal starts to corrode rather quickly.

This is what a used EPDM Powder Coated steel drop link looks like!

So why choose between HDG or Powder Coating when you can have both in Duplex Finish?

We don’t like installing a dull looking part or a part that will look good for a short period of time but then eventually corrode on our own bikes. Guess no one does. Every rider that we know of, who is passionate about their bikes likes to use the highest quality product that truly lasts. Since we have the capability, experience and know-how to manufacture high tensile strength steel parts with Duplex Finish, without substantially increasing the price, we thought why not.
As a result we started manufacturing 3B Racing Lowering Link Kits, made out of special high tensile strength steel with Duplex Finish that can truly outlast the lifetime of your motorcycle. We think you’ll also appreciate the quality of Phantom Black Matte finish in these products.

3B Racing Drop Link with Duplex Finish

Since we are confident in our manufacturing process, 3B Racing Lowering Link Kits with Duplex Finish come with a Limited 5 years (Five years) Warranty against corrosion.     

*Please kindly note that the link opens up in a new window taking you over to a third party website, namely Galvanizeit.org that belongs to the American Galvanizers Association.
Triple B Worldwide, Inc. has no affiliation, and/or association, whatsoever with the American Galvanizers Association, nor their website Galvanizeit.org. The link appears on this page in order to provide you more information on the subject and for citing the source of the quote used on this page.

Triple B uses special high tensile strength carbon steel for 3B Racing suspension links (drop and drag links) with Duplex Finish. Some of you may ask, why Carbon Steel over Stainless Steel (S/S)?

The short answer is, on a moving, structurally crucial  part, Stainless Steel becomes brittle under stress and can fail without  warning. So Stainless Steel is not a suitable material for suspension links

The longer answer is, suspension links are moving parts that bear heavy support loads, and they constantly move together with your bike’s working rear suspension. Therefore, flexibility and tensile strength are extremely important for such a moving part. On top of that, the material used in a suspension linkage must withstand both the heat cycles and the oscillating stress involved without hardening and suffering from metal fatigue. Stainless Steel hardens with each heat cycle and under stress becomes more brittle. Usually tiny hair cracks develop in S/S before failure but these can be hard to spot, especially without proper lab equipment.

Currently there is not a single motorcycle manufacturer that we are aware of that uses Stainless Steel for suspension links. And the reason for this is really simple: No one wants a suspension linkage failure.

So at Triple B, we also use special high tensile strength carbon steel but with the added benefit of an industry first: Duplex Finish.

We take pride in our products and 3B Racing suspension links will truly outlast your bike’s lifetime!

The problem with Stainless Steel in more detail:

The greatest safety concern with Stainless Steel for load-bearing moving parts is notably its modulus of elasticity and the fracture point which cannot be determined accurately. The fracture point (force/area) when failure occurs is not consistent for stainless steel, failure may occur already at as little as half the force for material that has sustained repeated pulling forces over time, compared to laboratory test of new material.

So at Triple B, we do not put our customers at risk and use special high tensile strength carbon steel with an industry first, Duplex Finish.

3B Racing Drop Link with Duplex Finish

Since we are confident in our manufacturing process, 3B Racing Lowering Link Kits with Duplex Finish come with a Limited 5 years (Five years) Warranty against corrosion.