Testing the Polygon Siskiu T7E was a rollercoaster ride, with a terrifying battery ejection, but fixing the issue made it my budget e-bike test winner

Polygon builds on the success of the popular Siskiu T series analogue trail/enduro bikes, by going all in on a sleek new e-bike version with the same progressive geometry and ride-hard attitude. There are currently only two models in the range and we are testing the top-end Siskiu T7E. But can £4k really get you an enduro worthy e-bike? And is it worthy of a spot on our list of best budget e-bikes? Time to find out. Polygon Siskiu T7E Need to know Enduro ready e-bike with a Shimano EP801 motor Shimano 630Wh removable battery 29in wheels as standard Geometry flip-chip for MX wheel conversion Fully adjustable SR Suntour suspension 150mm travel fork, 144mm travel frame Four-piston Shimano SLX brakes Shimano SLX 12-speed drivetrain Weight 24.62kg (54.28lb) size L Frame and geometry The burly aluminium Siskiu T7E frame is designed around Shimano’s excellent EP801 motor and 630Wh removable battery. It comes stock with 29in wheels, but the frame also sports a flip-chip to correct the geometry for an MX setup with a smaller 27.5in rear wheel. Now, given that Polygon offers the Siskiu T7E in four frame sizes, S to XL, and that the flip chip is such a great feature, we’d like to see Polygon deliver the size small and medium bikes with the 27.5in rear wheel as standard, as this would offer shorter rider more room to get off the back of the bike on steeper descents without buzzing the rear tyre. With a short 435mm seat tube, our size L test bike had plenty of standover clearance. It also had considerably slacker and lower geometry than claimed – 2º slacker at the head tube and 12mm lower in BB height! It was also the only bike in test with a relatively short 445mm chainstay length. Taken together, the Polygon instantly felt like a modern enduro e-bike. No bad thing, right? And that wasn’t the only anomaly. We couldn’t find the claimed frame travel for the Siskiu T7E anywhere on Polygon’s website, but seeing as we measure all of our test bikes, we know for sure that the Siskiu T7E pumps out 144mm of vertical rear wheel travel. Overall, the details on the alloy frame are neat. The bridgeless seatstays offer stacks of mud clearance, but we’d like to see the chainstay protector extend all of the way along the chainstay, like on the Decathlon Rockrider in this group test, because even after a couple of rides the paint was chipped next to the chainring where the chain had been hitting the frame. Not only would this protect the frame finish, it would also ensure an overall quieter ride. Suspension Most entry-level e-bikes don’t come with all of the top-end suspension bells and whistles. That’s clearly not the case with the Polygon, the SR Suntour suspension offering both adjustable rebound and compression damping and then some. The piggyback Suntour TriAir2 3CR rear shock features rebound adjustment and a three-position compression lever to firm things up for climbing. And … Continue reading Testing the Polygon Siskiu T7E was a rollercoaster ride, with a terrifying battery ejection, but fixing the issue made it my budget e-bike test winner