High roller built for comfort and mileage
When I saw this near SL-II spec Challenge Seiran 26″ USS in the LaidBack showroom I couldn’t resist taking some photos, but I didn’t ride it, as it wasn’t a demo – just waiting around to be boxed and shipped to its happy owner.
I thought it might be especially useful to put the Seiran up against the wall and compare it with the Furai 24″ which I reviewed in depth earlier this year:
Roll over for a comparison between the Furai 24 and Seiran 26
Despite the wheels only being a little larger (1″ greater radius) you can see that the Seiran dwarfs the Furai, with a seat height of around 62cm versus 46cm (24 1/2″ vs 18″).
Both bikes fill a similar role- big days on the road, potentially with a heavy load, but not racers. The carbon SL-II seat on the Challenge Seiran doesn’t preclude the use of a rack (although it would be an aftermarket mod unsupported by Challenge, plenty of people drill carbon seats for tailboxes) – I think this bike is intended more for a seatbag like the Radical Solo Aero though.
The front edge of the carbon seat is nicely down-turned which helps get the feet flat on the floor, but I wouldn’t want to be much shorter than my 5’10” (~43″ x-seam) – this was about my limit to get my heels on the ground, which is pretty much a pre-requisite of a well-mannered urban bike.
I thought that Challenge fitted Velokraft carbon seats, but the seat on this Serian is quite different to my own VK seat (which might just mean Kamil makes seats differently now, or makes them differently for Challenge, or indeed they come from somewhere else).
Either way, it’s a slender item – mine weighs 580g which isn’t much more than the 440g of a Ventisit seat pad!
The bike was fitted with a lovely pair of carbon cranks and a very light looking chain (hollow pins and side plates..!) but does still feature the aluminium boom, hence “near SL-II”.
The next couple of shots are just close-ups of the USS mechanism. It seems to be quite a nice clamp-on solution that (in theory) could be fitted to any kind of fork:
The bars on the USS Challenge Seiran can be adjusted for angle and width using an allen key (signficant narrowing might require you to use a hacksaw!)
If the carbon’s not enough, the Seiran can also be specced with a variety of shocks to further improve the ride and handling (especially with a load):
There’s plenty of clearance for big tyres, with full mudguards. BB7 discs and Velocity rims round out the package.
Being able to use standard tyres might be a good reason to go with the Seiran over the Furai (especially if venturing into less-travelled parts of the world where 700C and 24″ sizes are like hen’s teeth). However, if you’re staying local, Schwalbe do a strong range of tyres in both sizes.
Without riding this bike, I can hardly make any recommendation. There’s no reason not to expect it to roll along like a champion, and it looks the business.
It is really big – it’s perhaps worth noting that the Seiran is so much bigger than the Furai that the bikes weigh the same, even though this Challenge Seiran is built nearly to SL-II component standards.
Overall, the feel is almost like a high-racer (although the USS will give no steering obstruction problems like open-cockpit does) – shorter riders will certainly want to look at the Challenge Seiran 24 or Challenge Furai 24 as alternatives.
If the chance to ride one comes my way, I’ll provide fuller coverage of course.
- My main Laid-Back reviews page – all recumbents on one page