This summer, I learned how capable the combination of a lightweight carbon frame, 140mm of travel and 27.5+ wheels can be! I got a chance to test Rocky Mountain’s 2018 Pipeline Carbon 70, and was delighted to discover it’s a highly versatile and very fun bike that encouraged me to push my limits on both the ups and downs.
Aboard the Pipeline I found myself suddenly enjoying the tougher sections of climb trails, and on the descents I was pushing corners and creeping down rock slabs with a new level of confidence. The plus sized tires on the Pipeline’s lightweight frame makes this bike feel like a rally car with monster truck wheels.
This was my first experience on plus-sized wheels, and I was immediately impressed with the traction but also surprised how much the tires help absorb impacts. Even compared to the last bike I rode with 2.5” tires on 29mm wide rims, the 2.8” treads on 35mm rims made such a difference that the 140mm Pipeline felt almost as plush as my 160mm bike.
The big tires also carry momentum well, and I felt like I was climbing faster than ever on the Pipeline. My local trails saw an arid summer, but no matter how steep and loose it seemed I could clamber up anything without spinning a tire. Descending traction was equally inspiring, particularly in the corners where the extra width lets you lean over just a bit further. Also, if you like inching down rock slabs you’ll love the extra grip the plus tires provide.
The top-of-the-line 2018 Pipeline 70 features a full carbon front and rear triangle. This frame borrows a design cue first seen on Rocky Mountain’s Maiden DH bike; the Pipeline’s pivot at the chainstay/seatstay is hidden from view, and only accessible from the inside. While the frame looks slim overall, the head tube junction and chainstay yoke are noticeably beefy.
I really enjoyed Rocky Mountain’s four-bar Smoothlink suspension. I loved how supple yet poppy this bike felt when descending, but it does rely on its multi-position shock for efficient climbing. Pedalling the Pipeline with the shock wide open, I could see the bike bouncing with every stroke. Thankfully modern shocks have different modes to compensate.
The frame’s rear end offers plenty of clearance for the stock 2.8” tires. Cables are internally routed through the downtube but run externally on the rear triangle. The Pipeline uses a press fit BB, a Boost 12x148mm rear axle (and 110mm front), and there’s one bottle cage mount on the inside of the downtube. I really like Rocky Mountain’s integrated Spirit Guide. It’s a sleek and simple unit that bolts directly to the chainstay, and it did its job- I never dropped a chain.
The Pipeline provides what I’ll call a ‘classic modern’ fit and feel. I ride medium-sized frames, and this one felt comfortable right away. Its lengthy 601mm front end, 435mm chainstays and steep 74.6 degree seat angle combine to center your body nicely between the wheels. The best part is, Rocky Mountain’s Ride 9 chip allows you to fine-tune the geometry and shock rate. The figures above are based on the neutral position (5), but the Pipeline gives you nine positions to play with.