The Polygon Siskiu T9

Serious Bang For Your Buck

Words by Robert Johnston
Photos & Video by Brian Niles/Treeline Cinematics


Polygon has established themselves firmly as a brand who excels in terms of value proposition, with a range of reasonably priced mountain bikes that are still down to be ridden hard. With the Siskiu T9 though, the spec list reads a little different to usual, with high-spec components throughout that may have you expecting a high price tag to accompany. At under $3,000 though, the Siskiu T9 will avoid sticker shock for most riders, and the performance it delivers as a result of its high-quality spec is quite impressive. Read on to learn all about it.

As with all of our Dissected Features, this is not intended to be a long term review or endorsement of a product but is instead a chance for our viewers and readers to get a deep dive look into some of the newest tech and products in the mountain bike space. We thank Bikes Online for the opportunity to create this feature and getting you some valuable beta on this impressive value Trail MTB.

2024 Polygon Siskiu T9 Profile Photo


The Siskiu is Polygon’s All Mountain machine, designed for long days in the saddle but still packing capability to tackle some fairly gnarly descents. It’s been around for a little while at this point, but continues to feel modern and packs some impressive versatility and all around fun. Offered in a range of specs at various price points, the value proposition on these bikes is very high and the performance level for the money is excellent.

The Polygon Siskiu Frame | In order to offer the best fit and performance for riders of all sizes, Polygon takes a size-specific approach to the wheels on the Siskiu. They fit a pair of 27.5” wheels with a specific frame on the Small; offer the choice of dual 27.5” or dual 29” wheels on the size Medium; and fit a pair of 29” wheels on the Large and XL frames to suit taller riders best.

27.5” wheel-equipped bikes receive a 140mm travel rear end with a 150mm fork, whereas 29ers have a 135mm rear end and 140mm fork. The rear suspension is delivered by a Linkage Driven Single Pivot – or “Faux Bar” – platform, offering dependable performance.

ALX | Polygon manufactures the Siskiu frame out of their top-spec ALX aluminum. This combines triple-butted 6061 tubing with complex forgings to minimize weight and keep strength where required, and is heat treated to ensure it’s in it for the long haul.

One Piece Linkage | Polygon opted to forge the main suspension linkage in one piece, creating a unibody structure at the heart of the Faux Bar suspension system for a stiffer and lighter weight connection.

Paint Job | Typically bikes in this sort of price range are given a fairly simple paint job that reflects their budget positioning in the market. For the T9, Polygon produced a stunning metallic forest green and black paint job, which looks great in the flesh and matches the high spec componentry.

Features | Polygon opted to go for full internal cable routing to give clean looks and keep the cables out of harm’s way. Within the front triangle there’s room for a large water bottle to ensure you can stay hydrated.

The Siskiu comes with all modern frame standards you might expect, from a threaded bottom bracket to boost axle spacing. There’s even some ISCG-05 tabs fitted to let you run a chainguide with bashguard if you’d like to add the extra protection.

Polygon Siskiu T9 Dissected

Geometry | Polygon wanted to ensure their Siskiu trail bike retained plenty of fun factor, without sacrificing capability for slightly gnarlier descents or how well it climbs. Standing out for this category of bike is the short chainstay length – just 430mm on the 29” wheel frames – and the low BB sitting at 335mm to keep the rider nicely integrated into the bike.

Depending on the wheel size selected, the geometry differs slightly to provide the best performance. For example, the head tube angle on the 29” wheel-equipped frames is half a degree steeper to regain some steering agility.

The size range goes from Small to XL, and riders will appreciate the small 20mm jumps in reach as you climb the size range, letting them get close to the perfect fit.

Stack heights are low on the smaller sizes to allow shorter riders to obtain a low enough bar height. Larger riders receive higher stack heights to avoid the need for excessively high handlebars in order to obtain the desired riding position.

A 76.5-degree effective seat tube angle should leave most riders in a nicely centered spot when climbing in the saddle, without being overly upright for flatter seated efforts.

2024 Polygon Siskiu T9 three quarter view


Polygon is offering the Siskiu in a range of build specs from the T6 at $1,699 to the T9 at $2,999. As you step up the range, you get the same proven Siskiu Trail frame, but the part spec increases in quality. That means you could buy one of the cheaper Siskiu models and upgrade to get something similar to this T9 build over time. But opting to get the T9 initially is likely to yield some significant cost savings compared with upgrading the parts yourself.

Looking at the sub-$3,000 Siskiu T9, the spec fitted is very impressive overall in terms of bang for your buck, and the result out on the trail is notable.

Suspension duties are handled by Fox, with their highly tunable 36 Performance Elite fork and a Float X performance shock. Both are air sprung for easy setup and lighter weight, and the fork features full 4-way compression and rebound adjustments to help you get the performance dialed in to your liking. The rear shock has an easy-to-reach lockout lever to quickly boost pedaling efficiency on the climbs.

Taking a look at the drivetrain, there’s a Shimano XT shifter, derailleur and crankset, with a Deore 12 speed cassette featuring Hyperglide + shifting technology. This has a full 10-51T range to help to get you up the steepest climbs.

2024 Polygon Siskiu T9 Brake Spec

The braking is provided by a pair of powerful and dependable TRP DH-R EVO brakes, with 180mm rotors allowing them to be modulated more easily. These are some of our favorite brakes on the market, so it’s great to see them fitted to a bike at this price point.

Polygon opted to use the Trans X dropper post, which uses the very common JD internals. Small and Medium sizes get a 150mm drop unit, whereas the L and XL get a 170mm drop. This is topped with a WTB Volt saddle.

The cockpit is by Polygon’s in-house brand Entity, with the Expert 35mm diameter alloy bar with 780mm width and 25mm rise, and a 35mm long expert stem. These aren’t flashy offerings, but look clean and have comfortable geometry for most riders.

Entity also provides the XL2 double wall alloy rims, with a 35mm inner width to suit the 2.6” Maxxis Assegai EXO tires. These are laced to dependable Shimano hubs, which should keep rolling for many miles.

Overall for $2,999 rrp, it’s fairly safe to say the level of componentry on the Polygon Siskiu T9 is quite exceptional. But can the spec elevate the performance of this bike to new heights? Keep reading to find out about how the Polygon Siskiu T9 has performed on the trails so far.

2024 Polygon Siskiu T9 Descending


As with all of our Dissected features, this is not intended to be a long-term review of this bike or a report on its durability. So far, we’ve managed to log a couple of solid rides to get an initial impression of its character, and it’s safe to say we’ve had a good time doing so.

We’ve previously enjoyed a time on board lesser-spec’d versions of the Siskiu, but the T9 has really proven to us that the Siskiu Trail frame is a solid performer – especially for the money – and that the components on the cheaper builds limit its ultimate capabilities.

Spec Impressions | Suspension performance improves considerably once you climb out above the entry-level units, and the Fox 36 Performance Elite fork and Float X shock offer an excellent suspension package that we’d be unlikely to upgrade if we owned this bike ourselves.

The TRP DH-R EVO brakes are incredible to see on a bike at this price point, offering up fantastic power in a controlled manner, even with the 180mm rotor spec. These are brakes we’d happily run on a dream build, never mind a bike under $3k.

The mainly Shimano XT drivetrain feels great to shift and never skipped a beat, and though the Deore cassette adds a little weight, it’s also a longer lasting option thanks to all of the teeth being steel. They still save some weight thanks to an alloy spider, so it’s not overly portly.

The Entity cockpit is the first area of the spec that lets down the premium looks a touch, but on the trail it offers solid performance and certainly doesn’t impact the overall function of the bike. The Entity XL2 rims are sturdy, but certainly on the heavier side and contribute to the fairly portly overall weight.

The TransX dropper post is no-nonsense and goes up and down without a fuss. I don’t love the feel of the lever, but it’s passable. The Entity grips are comfortable, which is more than can be said for many stock grips, so that’s one less thing riders are likely to need to upgrade straight out of the box. And that’s really the theme overall here – all but the most discerning riders are going to be able to ride the Siskiu T9 happily, straight out of the box.

My one gripe with the spec choice is the rear Maxxis Assegai EXO 2.6” tire. I love the Assegai, but feel like the 2.6” EXO tire doesn’t make a huge amount of sense for this bike. It’s also very wide for the rear triangle, leading to some clearance issues. I’d rather see a slightly narrower, lower profile tread pattern, and perhaps a bump up to an EXO+ or Double Down casing to better match the rowdier intentions of the piggyback shock and Grip 2-equipped fork.

2024 Polygon Siskiu T9 Climbing

Riding The Polygon Siskiu T9 | In terms of trail character, with this capable suspension package, powerful brakes and solid wheels, this Siskiu T9 is a serious amount of fun. It avoids any notions of being in the more affordable space, and lets you just focus on enjoying the trail ahead.

The Siskiu is not the lightest and most efficient bike, but even so it is a comfortable machine to climb. The geometry puts you in a good position to balance steep terrain pedaling ability and comfort on flatter stretches. The suspension platform offers plenty of support without being overly harsh, and the lockout lever on the Fox Float X shock is easy to access on-the-fly to quickly boost efficiency for smoother stretches. Pedal clearance can be an issue in the tech at times due to its low bottom bracket, but it’ll be manageable in most parts of the world.

On the descents, the geometry lends itself to being playful, which is backed up with plenty of support and pop in the suspension to let you have a good time. The riding position is poised and comfortable, with the short rear end letting you quickly pop the front wheel up for a manual or wheelie and the low BB giving excellent feeling of integration and safety between the wheels.

In the rough stuff, the Siskiu is about average in its category. It is still absolutely capable of tackling some rough and rowdy terrain thanks to the excellent sensitivity and control of the Fox suspension package, but with a trail bike mindset that’ll have riders avoiding the most chunky lines.

Aside from some easily remedied rear tire clearance issues, the Siskiu T9 ran quietly and felt every bit as dialed as bikes twice the price. Polygon has done a killer job at putting this bike together, and we’re sure that many riders would be stoked on it after dropping their hard earned cash. If you think the Siskiu T9 is for you, then be sure to head to Bikes Online to pick one up if you’re in North America.

2024 Polygon Siskiu T9 Dissected