Trek Rumblefish FS 29er Review

The Trek Rumblefish is a beautiful mountain bike with clean lines, modern hydroformed tubing, asymmetrical chainstays, and hot graphics that I had to ride during my time at Interbike. Like the other Gary Fisher 29er descendents, the Rumblefish has a reputation for being a solid big wheel bike with excellent handling characteristics.

The 2012 Rumblefish is currently spec’d with 110mm of rear travel and a 120mm travel fork which is a bit unconventional most manufacturers prefer to match front and rear travel numbers. The rep I spoke with admitted the set-up wasn’t ideal and that the frame designers were still trying to make the geometry work (early adopters beware!).

Even with just 110mm of rear travel, Trek classifies the Rumblefish as a Trail bike which is traditionally 5-inch (120-140mm) travel territory. Of course some will argue that a 29er effectively rides like a longer travel bike than one with 26-inch wheels, making it difficult to pinpoint equivalent ranges of travel for big wheel bikes (XC vs. Trail vs. AM, etc.). Anyway, enough with semantics and classifications I wanted to see how the Rumblefish handled itself on the trail.

On the climbs the Rumblefish definitely felt dialed in and efficient. While other companies are turning to carbon frames to moderate the 29er weight penalty, the Rumblefish is actually quite light despite its fully-suspended aluminum frame. On the descents the Rumblefish was agile and responsive and I had a hard time finding fault with the mismatched front and rear travel. This bike, like most of the other FS 29ers I rode, was a lot of fun on the trail and the geometry felt just right to me.

Still, I never got the feeling that this bike was more of a “Trail” bike than any of the other 29ers I rode at Outdoor Demo. Just about the only thing that screamed Trail to me about the Rumblefish was the wide, 2.4″ Bontrager tires on the demo model. If you ask me the Rumblefish (starting around $2,400 MSRP) rides like a fast, fun big-wheel XC bike in the same way as the Giant Anthem X does. It will definitely be interesting to see how the frame and geometry on the Rumblefish evolves over time!

Update: The Trek website is now showing the 2012 Rumblefish comes with 120mm of travel front and rear (thanks Neil!). The rep we spoke with at Interbike apparently didn’t have the latest information – either way, the bike rode well!