On Test | The New 2020 Polygon Siskiu D6 Is A Full Suspension Trail Bike For Less Than $2,000


It’s no secret that there are some seriously expensive mountain bikes kicking around in 2020. What with all the SRAM AXS wireless stuff, Fox Live Valve automated suspension and carbon whizz-bangery. Oh, and the fact that many are now coming with an electric motor now too. Add in a tanking Aussie dollar and fluctuating global currencies, and the price for the cutting edge continues to rocket skywards.

Seeing as it’s the premium end of the market that typically enjoys all of the media hype, it can be easy to forget that entry-level mountain bikes have been evolving and improving too though. Now more than ever, the technology we see at the top-end has been quietly trickling its way down, and as a result we’re seeing better and vastly more capable entry-level bikes. Case in point – this new 2020 Polygon Siskiu D6.

2020 polygon siskiu d6 full suspension mountain bike
Polygon has got a new Siskiu D trail bike for 2020, and we are digging what we see.

What Kinda Bike Is The Polygon Siskiu?

Indonesia’s Polygon has had the Siskiu in its lineup as far back as 2016, when it replaced the Recon as the brand’s popular full suspension trail bike. Highlighting the popularity of the platform, the Siskiu has since split into three distinct versions with differing amounts of suspension travel, and differing intentions;

Within each platform you’ll find various spec levels, which are denoted by a number. The higher the number, the higher the spec (and the price).

We’ve tested all three platforms over the past few years, including the Siskiu D8, the Siskiu T8, and the Siskiu N9, all of which have offered stonking value for money. It’s been a while since we’ve had a Polygon in at Flow HQ though, and having caught wind of a new changes to the Siskiu D platform for 2020, we decided to get one in to see how exactly what’s changed, and just how good this sub-$2,000 full suspension bike really is.

2020 polygon siskiu d6 full suspension mountain bike
Up front is a 120mm travel SR Suntour fork with an adjustable air spring, rebound damping, and a lockout.
2020 polygon siskiu d6 full suspension mountain bike
There’s an X-Fusion air shock also with adjustable rebound damping and a lockout. The shock is driven by the seatstays with a neat one-piece rocker link connecting them to the seat tube.

Any Changes For 2020?

Loads! At its core, the Siskiu D remains as a value-packed alloy trail bike, which uses a single pivot suspension design with a linkage-activated rear shock. Travel sticks to 120mm front and rear, though the kinematics have been updated to provide a more progressive leverage rate. Overall it’s designed to provide good pedal efficiency for the climbs, with enough cush to make the descents more comfortable, and more fun than a hardtail.

Frame geometry has also had a hefty refresh. The head angle is slacker (now 67.5°), the seat angle is steeper (now 76°), the bottom bracket is lower (now 326mm), and the top tube has been made longer to facilitate the use of a shorter stem. And by moving to Boost 148x12mm rear dropouts, Polygon has also tucked the chainstays in further (now 436mm).

The geometry and suspension updates also mean there’s now room for a water bottle inside the mainframe, just below the rear shock. Su-weet!

2020 polygon siskiu d6 full suspension mountain bike
For 2020, the Siskiu D gets a slacker head angle, a steeper seat tube angle, a lower BB and shorter chainstays.

Err, How Much?!

We don’t normally harp on about price here at Flow, but it’s impossible not to mention that when you’re talking about a full suspension bike that sells for less than most carbon wheels on the market. For 2020, there are three spec levels available in the Siskiu D range. We’ve got the Goldilocks D6 model on test, which is sandwiched by the D5 and D7;

Worth noting is that the cheapest Siskiu D5 only comes in S-L frame sizes and with 27.5in wheels. In comparison, the D6 & D7 models spec 27.5in wheels on the Small size, while M-XL sizes come with 29in wheels.

Now if you’ve read any of our Polygon reviews before in the past, you’ll know that the bikes are sold direct-to-consumer in Australia via Bicycles Online, a big reason why the pricing is so sharp. It also means that if you do decide to purchase one, it’ll turn up on your doorstep in a cardboard box, and requires a small amount of assembly to get it rideable. It’s all pretty easy, and Bicycles Online has some great video resources on how to carry out the various steps required to get you rolling on the trail. There is an additional shipping cost though, which is calculated based on your postcode.

2020 polygon siskiu d6 full suspension mountain bike
While the frame is 2x compatible, Polygon has spec’d the Siskiu D6 with a Shimano Deore 1×10 drivetrain.

Siskiu D6 Highlights

We’ve only just finished building up our test bike, but already we’re impressed with the attention to detail that Polygon has gone to. For a start, you’ve got air-sprung suspension front and rear with adjustable rebound damping, which means a shock pump is all you need to increase or decrease pressures to set the bike up for your weight and riding style.

There’s also an internally routed KS dropper post, 760mm wide handlebars and a stubby 45mm long stem. And while the wheels may not be tubeless ready out of the box, Polygon has spec’d double-wall alloy rims with a 25mm internal width to support the 2.25in tyres. Props for the ‘Spiderbait’ tyre name too – we love it!

You’ve also got Shimano hydraulic disc brakes, along with a Deore 1×10 drivetrain – an excellent choice that delivers a much cleaner setup than a 2x drivetrain, and that’s allowed Polygon to spec a proper under-the-bar remote for the dropper post. All good stuff that isn’t necessarily standard fare on a bike of this price.

But while there are certainly lots of nice details and plenty of value to be found, but just how good can a sub-$2,000 full suspension perform? Are you better off with just getting a better-spec’d hardtail instead? Those are questions we hope to answer over the next few weeks as we get stuck into our new Budget Bouncer. In the meantime you can check out the full specs below, and make sure you shoot us through any questions.

2020 polygon siskiu d6 full suspension mountain bike
Suspension kinematics have been updated to work with a shorter-stroke shock, which provides a more progressive spring curve.

2020 Polygon Siskiu D6 Specs

2020 polygon siskiu d6 full suspension mountain bike
760mm wide hangers with a stubby 45mm long stem on all four frame sizes.
2020 polygon siskiu d6 full suspension mountain bike
Just how well can a sub-$2K full suspension bike ride? Stay tuned for our full review of this Budget Bouncer!

Mo’ Flow Please!

Enjoyed that article? Then there’s plenty more to check out on Flow Mountain Bike, including all our latest news stories and product reviews. And if you haven’t already, make sure you subscribe to our YouTube channel, and sign up to our Facebook page and Instagram feed so you can keep up to date with all things Flow!

It appears you're using an old version of Internet Explorer which is no longer supported, for safer and optimum browsing experience please upgrade your browser.