Inside Line: Rocky Mountain expands Thunderbolt line with carbon frames

Take a peek at the new Rocky Mountain Thunderbolt MSL. We have an aluminum version of the 120mm chassis in for testing now, but before we could finish our review the team from British Columbia have upped the ante with a carbon fiber frame.

Blurring the lines between cross-country and trail, the Thunderbolt MSL pairs 27.5 wheels with an all-new Smoothwall carbon frame with a bit of a first for Rocky Mountain. By switching to a the new Pipelock main pivot, all the pivots now move on bushings rather than bearings, and with grease ports in key locations, they say it provides a stiffer, lighter and easier to maintain bike.

Like the aluminum bike we’re riding, the Thunderbolt MSL uses Rocky Mountain’s Smoothlink suspension design, but where it differs is the inclusion of the Ride-9 geometry adjustment. First seen in the Altitude bikes, the Ride-9 system allows for nine different shock mount placements for a huge range of suspension tuning based on how you want the bike to perform. Two interlocking chips let you adjust for terrain, style and rider weight.

Keeping on top of all the modern technologies, the Thunderbolt MSL frame is compatible with Shimano XTR Di2 with full internal cable routing with an integrated stealth battery port in the downtube. The BB92 bottom bracket keeps things extra stiff where they need to be.

If you’re into the numbers, the head tube angle is a pretty aggressive 67.2-68.4 degrees, depending on how you set up the Ride-9 chip. This ain’t your grandpa’s XC bike. The chainstays are an extra short 16.6 inches too, so it should feel just as fun and nimble as the aluminum version.

There are three models of Thunderbolt MSL for 2015:

779 MSL

• Shimano XTR Di2 11-speed
• Fox Float suspension
• Stan’s NoTubes Valor carbon wheels
• RaceFace Next SL carbon crankset
• Rockshox Reverb Stealth dropper post
• $10,999

770 MSL

• Shimano XT brakes and drivetrain
• Fox Float suspension
• Shimano XT hubs laced to Stan’s NoTubes Crest rims
• RaceFace Turbine 2x crankset
• Rockshoxk Reverb Stealth dropper post
• $5,499

750 MSL

• SRAM X7/X9 drivetrain
• Shimano SLX brakes
• Fox Float suspension
• Shimano SLX hubs laced to SunRingle rims
• Raceface Turbine 2x crankset
• X-Fusion HiLo dropper post
• $4,299

But wait, there’s more…

The folks at Rocky Mountain love to get rowdy on a bike, especially in their home turf in British Columbia, so they’ve created the BC Edition line of bikes that are built just a little more burly.

The Thunderbolt MSL gets the BC Edition treatment for 2015 with wider bars, shorter stem, bigger tires and stronger wheels. The geometry gets tweaked thanks to the addition of a 130mm Rockshox Pike with a new head tube angle of 66.5-68.2 degrees.

790 MSL BC Edition

• Rockshox Pike RT3 fork and Monarch RT3 shock
• SRAM X0-1 drivetrain with RaceFace Turbine direct-mount crankset
• Shimano XT brakes
• Stan’s Flow EX wheels
• Rockshox Reverb Stealth dropper post
• $6,399

The Thunderbolt MSL models will be available in Rocky Mountain dealers this fall.