Seismic Defcon Bushing: Deep testing by Phil Dupuis

Famous for its high-end wheels highly valued by downhill competitors (Fulkit's Boss Pierre was one oth their team riders on the world circuit from 2009 to 2011), Seismic is now venturing into the production of bushings. Our friend and tester Phil Dupuis had the opportunity to experience these new precision accessories, and here is his feedback after numerous sessions...

For some time now, I've been experimenting with adjustments on my skateboard trucks to make comparisons between the recently introduced Seismic Defcon bushings and the brands I commonly use, such as Riptide, Bones HC, or the 'discontinued' Abec11. Additionally, I've been testing the Jimmys that come with Bear trucks and occasionally trying out Sabre or Divine bushings on Paris trucks.

It's amusing to note that some bushings are even significantly more effective on different trucks than the original brand, just as some excellent trucks may come with completely inappropriate bushings from the factory. Never hesitate to make changes if you want to explore all aspects of a setup!

So far, the Seismic Defcon bushings are only available in a barrel shape, but notably, in three different heights: standard/15mm (0.6 inch), medium/16.5mm (0.65 inch), and tall/19mm (0.75 inch). All of these come in 8 durometers: 73A, 77A, 81A, 84A, 87A, 90A, 93A, and 97A.

As far as I know, only Chris Chaput's from the Abec11 brand had released bushings that play on these three heights within the same range. While the standard height is the most widely used, when it comes to freeride and downhill trucks, an increasing number of manufacturers are opting for geometries that incorporate tall barrels for the depth they provide in turns (the lean). Some trucks can combine both heights, whether intended or not.

It's actually a setup that I really like, especially with a standard barrel on the board side and a tall one on the roadside, to play with an initial consistent lean and a firmer lean towards the end."

For the Seismic Defcon bushings, I had the opportunity to try out the standard size, as well as a pair of medium and a pair of tall, available in 84A, 87A, and 90A durometers. It's worth noting that across various brands, I most commonly use hardness within this range. These cushions come in vibrant and distinct colors compared to competitors, making them easy to identify.

A big thank you to Pierre Gamby from Fulkit, for his contribution and unwavering commitment to the longboard scene!

We could notice that the less common medium size corresponds to the Bones Hardcore of Aera trucks as well as the geometry of Sabre trucks. This is primarily how I have ridden this 16.5mm dimension, on RF-1 and Sabre forged trucks in 150mm.

For standards and tall, I tested it on slalom trucks from Tracker and Bennett, machined Hakis from Don't Trip, chopped Reverse Gullwings, and 160mm Kodiaks. The truck widths I most commonly ride range from 130 to 160 mm. Another specificity that is less common among riders is that my rear truck is set softer than the front, even when it has less angle, and not harder. Whether on a very long board or an 80cm board, this setup suits my riding style better, with a light rear foot, within my speed range (70-75 max). It is also in this mindset that I choose my bushings, with each rubber having its own 'personality'.

Test

Overall, I would have ridden these Defcon bushings in 90A duro less. It must be said that for my current habits and sensations, it's already at the top end of the hardness range, so a bit firm. In terms of rebound, these new bushings would fall between Riptide APS and Venom, but the sensation can vary from one duro to another.

As I rarely equip my setups with a single bushing model, I preferred to continue comparing them in this way, alternating the position (roadside/boardside, front/rear, etc.), the type of truck, and their coexistence with other brands. I've become a big fan of the Defcon 87A, which I find to be well-balanced between responsiveness and stability. They pair quite nicely with the 84 for a slightly softer setup in the same durometer, but they are also very interesting when combined with 87.5 and 90A Riptide APS, as well as Bones HC 88A, to either enhance or mellow out the truck's response. The Seismic bushings in these durometers respond well to tightening/loosening, allowing for a wide range of adjustments (the 90A 'turning off' more quickly for my 63 kg when applying too much tightness, so I had to let it live around the minimum tightness).

Note: Bushings perfectly tailored to the kingpin diameter, without any annoying play. Their dimensions are highly precise in thickness because one of the faces is machined after molding, ensuring consistent characteristics from one bushing to another. No rounded or hollowed ends, an even contact surface across the entire rubber. Thus, fewer unwanted movements.

In terms of behavior, they reveal in the supports a blend of sharp feedback without excessive bounce and a consistent lean in their depth. In a straight line, a configuration where I've had a bit fewer opportunities to ride lately, they seemed precise and predictable, without the nervousness of, for example, a Krank. Linear and energetic in their response, without any confusing aspects, they manage to maintain a well-defined central point.

Of course, our dear little bushings are subjected to quite a bit of mechanical stress and temperature changes. The urethane also evolves over time, so it can be said that, in general, their behavior softens gradually, and their rebound would tend to decrease with use.

"The Seismic Defcon bushings boast excellent craftsmanship, precise molding with few bubbles, a flat contact surface, and well-defined edges. There is no doubt that the brand's expertise and diligence in the chemistry and manufacturing of wheels contribute to the quality of this type of product. These Defcon wheels, therefore, represent a new range that proves to be both highly effective and enjoyable to ride, responsive without causing instability, allowing for clear and incisive turns. Numerous combinations await exploration!