2017 Yeti SB4.5
Size Tested: Medium
- Turq series frame
- Drivetrain: Shimano XT
- Brakes: Shimano XT
- Fork: Fox Float 34 Factory
- Rear Shock: Fox Float Factory
Travel: 114 mm rear / 140 mm front
StatedWeight: 27.8 lbs (12.6 kg) without pedals
Reviewer: 5’9”, 155 lbs.
Test Location: Moab, UT
We swung through Outerbike in Moab a few weeks ago to hang out, ride some bikes, and partake in the good times that happen when bike people gather together in the desert.
If you don’t already know about Outerbike, you should; it’s a great opportunity to demo new bikes on some great trails. There are three Outerbike events throughout the year — Moab in the spring; Crested Butte in the summer; and Moab again in the fall. Each event lasts 3-4 days, and you can get more information at outerbike.com.
So we had three days to ride some of this year’s new bikes on a smattering of Moab’s best trails. And while it was a great opportunity to learn a good bit about a number of new bikes (including the one reviewed here), we only rode these bikes for a few hours each, so keep in mind that this isn’t our normal full-scale review.
Last fall, I spent a while on the SB4.5’s big brother, the SB5.5. I said then, and still think now that for pretty much any trail that’s at least moderately pointed downhill, the SB5.5 is the fastest bike I’ve ever been on. But there are plenty of trails where the longer travel of the SB5.5 is overkill and a shorter travel wagon wheeler is the drug of choice.
Enter the SB4.5. Take the 5.5’s penchant for speed and blend it with a snappiness and efficiency that clearly has roots in the world of cross country race bikes and you end up with the SB4.5. So how’s that work as a trail bike?
The SB4.5 is available in a variety of builds and two flavors of frame – there’s the regular SB4.5, and there’s the Turq series frames, which incorporate some higher modulus carbon that saves a considerable amount of weight, but also adds a considerable amount to the price.
Like all of the SB series bikes, the SB4.5’s suspension is built around Yeti’s Switch Infinity design – a pair of little sliders made by Fox that help Yeti tweak the wheel path and dictate the leverage ratio on the suspension. For more discussion on that design, take a look at the SB5.5 review, where I also get into some longer term conclusions regarding durability of the system (synopsis: it holds up really well).
I rode the Turq version of the SB4.5 equipped with the XT package. As the name implies, the drivetrain and brakes are mostly Shimano XT bits, and they all performed nicely. The bike isn’t front-derailleur compatible, but the 30t chainring paired with the wide range 11-46 XT cassette made steep climbs entirely manageable. If I’m going to nitpick, I find the XT cassette to have too big of a gap in the gearing from the 37t cog to the 46t cog, but it shifted fine, so that’s a fairly minor quibble.
Suspension on all Turq series SB4.5’s is Fox Factory series, front and rear. Non-Turq bikes bump down to the Performance series suspension, which loses out on the Kashima coatings and gets a different damper in the fork. The 34 up-front and the Float on the rear of the SB4.5 that I rode performed flawlessly. I’ve spent a fair amount of time on that fork and rear shock on a variety of bikes, and I’ve found them to be consistently strong performers that have held up pretty well on the durability front. Notably, the fork comes set at 140 mm travel, which is pretty long for a bike in this class, and it affects how the bike rides — more on that below.
The SB4.5 was rolling on DT Swiss wheels, with 350 hubs laced to XM421 rims. The XM421’s are a great choice for a bike like this — wide enough to work well with bigger tires, but light enough that they don’t make the bike feel boat-ish. The 350 hubs are high on the list of most durable and easiest to service, but I will continue to gripe about their poor engagement, which is annoying on techy climbs.
Other noteworthy bits from the build kit: A Fox Transfer dropper post is a solid performer, and so far seems to be well-regarded in terms of durability. Maxxis Ardent tires aren’t a personal favorite of mine, but they’re a fairly safe, inoffensive choice on a bike like this. A Yeti carbon bar (740 mm) and an Easton stem (55 mm) work fine, although I’d lobby for a wider bar that could be cut narrower as needed.
NEXT: Fit and Geometry, The Ride, Etc.