2024 Polygon Siskiu D7, Large 29" pictured

Is This The Best Budget Short-Travel Mountain Bike?

After owning this bike twice, I feel like it's the best entry level full suspension on the market.

Evan Steinberg

4 Feb 2024

The Polygon Siskiu D7 is a short-travel trail bike with 120mm front and rear travel that I've owned twice now, and I can say its one of my favorite bikes, ever. Not just favorite bikes in its category, favorite all around.

Siskiu D7 Climbing — Siskiu D7 has some pep!

I am 5’9” and I chose a large. On my first ride, basically the first time I pedaled it, I was shocked on how responsive it was. It almost felt peppy like a BMX bike would. Navigating around corners was easier, the steering was more direct, I was having a blast. And looking back, I think this bike ended up making me a better rider.

With my previous bike, I was used to 2.5-2.6” tires. I thought that was the norm for mountain bike tires, the bigger the better. But the Schwalbe 2.3” tires on the D7 enhanced the ride. The big tires can really dampen the trail and soften everything. The 2.3” tires however made me feel the trail more. Before I knew it, I was taking different lines than before, not because I was clapping out the suspension, but the bike felt nimble, and treating it as such felt natural. Plus, changing directions, weaving from one side of the trail to the other, was much easier.

I wouldn’t feel right writing this review without mentioning 2 topics: the consensus of the frame cracking and the bike fitment issues I dealt with the second time I acquired this bike in the D7SE lineup.

Cracking - The D7 and the D7SE are a bit different. Other than some component changes, the D7SE also has a different frame gusset by the seatpost. I don’t have any knowledge as to why, but if you check forums and Polygon community groups, you will sometimes hear that the frame was prone to cracking in that area. As a mountain bike YouTuber, I get a lot of comments and hear about people breaking their bikes. Well I had a guy message me about how his D7 had a catastrophic crack. I asked why and he responded “well I just jumped off a stair set, I landed perfectly flat, so I don't know why it cracked”. I’ve seen other people jump and land in the sitting position with their seats all the way up. When investigated further, it seems like people are riding this bike outside of its intended use.

I can see why. This bike has a very low pricepoint, making it one of the cheapest, best entry level full suspensions on the market. BikesOnline and Polygon probably sell a ton of these, and maybe they are to people who are just buying what they can afford. Then their skills progress past what the bike can handle. Or maybe they’re exceptionally rough on the bike thinking that mountain bikes are meant to handle the roughest terrain (I thought that when I started).

Fit Issues - When I first had the D7, the bike fit me amazing. I had just come off a medium Vitus Mythique that I thought was too small. Then I got on the D7 and it just felt so perfect for me. At some point I did mention on video that the seat did not go low enough, but I never had issues of the seat hitting me in the butt during jumps, although I didn’t have a lot of jumps to hit in Phoenix, AZ.

With the D7SE, I had issues with the tall standover height. I ended up swapping to a OneUp dropper with an ultra low stack height and that helped the issue a lot. Additionally, I did a fun video converting it to mullet and that seemed to completely solve the tall standover height issue. I am 5’9” and its a height that is cursed when it comes to sizes and puts me right in the middle of Medium and Large with pretty much every brand. I’ve never tried a medium D7 or D7SE before, but I will update this article if I do.

TL;DR:

Polygon Siskiu D7 and D7SE are short travel trail bikes that are the best value entry-level, full-suspension bike on the market.

Great pedaling position
Nimble, snappy, makes local trails spicy
Changes directions well, encourages different line selection
It is not a huck machine, it has to be ridden gingerly
A bit heavy, unlikely that it can be upgraded to be <30lbs
Breath of fresh air for me coming off a tanky trail bike

Upgrades - With my first D7, I upgraded the bike to the moon to do some XC races, but I could never get the weight below 30lbs despite a TON of upgrades. The essence of this bike exists in the frame and it’s geometry. The biggest difference was upgrading to a lighter wheelset. And surprising enough, the stock Shimano MT200 brakes have plenty of stopping power for this bike. I even navigated a double-black diamond trail in the HAWES trail system by accident. As mentioned above, wheels would be the biggest performance upgrades. If that’s too expensive, at least going tubeless and removing the heavy tubes would really transform the bike in how its supposed to feel. But the great news is the frame is Boost spacing (148mm rear thru axle) and can handle all the modern parts upgrades. The D7 has a non-boost front hub, whereas the D7SE has a boost 110mm thru axle front hub and you won’t have compatibility issues when considering upgrades.

Geometry - Large 29”

Stack	615mm	Felt a tad low, ran a taller 35mm rise bar (I don’t like running a lot of spacers under the stem)
Reach	465mm	Great rider area for me
Head Tube Angle	67°	Nice and slack for a short travel, more than an XC bike, but not too slack where the steering is sluggish
Effective Seat Angle	76°	No issues with the seat tube angle at all
Wheelbase	1189mm	Very stable, yet playful. Able to take switchbacks with ease.
Standover Height	733mm	Pretty high for my liking. Couldn’t get low enough with drops and rock gardens, until I put a low stack dropper on

Components D7

Bike Part	Component	Comments
Frame	120mm travel, boost through axle, tapered head tube, internal cable routing	Comments on the ride above. The pictures of the frame really don’t do it justice. Great paint job with gloss and matte finishes mixed together. Uses all modern sizing meaning its ready for an upgrade.
Fork	RockShox Recon 120mm travel, non-boost	I have always gotten along with a fresh Recon. They feel great to me for an entry level fork. Sure its a little heavy, but its reliable. Its a bummer that its non-boost, but if you don’t plan on upgrades, thats a non-issue. If you do, the D7SE has a Suntour fork with a boost thru axle and the two are similarly priced.
Shock	Rockshox Deluxe Select 190x45	This shock was okay. Felt great, a little stiff compared to others I tried.
Drivetrain	Deore 11 Speed	Bombproof drivetrain and the shifting with your thumb feels so light. Just make sure you have the clutch on!
Brakes	Shimano MT200	These budget hydraulic brakes surprise me. If you’re riding greens, blues, and occasional blacks, they should have plenty of stopping power (as long as its not super steep). I’ve had to do emergency braking with these and they stopped just fine.
Wheels	Entity branded 30mm ID, sealed hubs	A tad heavy, but most stock wheels are.
Tyres	Schwalbe Nobby Nic Wire bead	Decent traction. Accidentally went tubeless and they held for months. Taking them off though after…difficult!
Handlebar & Stem	Entity 780mm	Nothing much to comment. Nice green accents.
Seatpost	KS Rage 170mm travel	Rock solid the whole time I used it. Dropper lever left a lot to be desired. With the tall standover, I couldn’t have it all the way up.

If you enjoyed this article and you want to check out the Polygon Siskiu D-series lineup more, follow this link. I also have several videos upgrading the bike and doing some fun things to it which I have linked below.

Disclaimer: BikesOnline did provide me with both Siskiu D7’s but no money changed hands and I was never once told what to say, in fact, honesty was encouraged. The above thoughts are solely my own.