We’ve been testing the Pocket Rocket for over two years now, and finally saw it fit to put into production. Its a 4″ travel URT design optimized for dirt jumping, park riding, and slalom racing. It does quite well as a short-travel trail bike to boot. In short, the ideal all-around play bike.
What is URT, and why are we using it? URT stands for Unified Rear Triangle – it means the bottom bracket is mounted to the swingarm rather than the front end. For this application, with this layout, its the perfect choice. Mounting the bottom bracket to the swingarm means zero chain growth – you can run it singlespeed without a tensioner, and geared with the shortest, tightest chain possible. Awesome. Also, no moving parts between your feet and your wheel mean excellent power transfer, perfect for gate starts.
But wait, how can the suspension work if you’re standing on the swingarm? Well, it works remarkably well. Imagine putting a pivot in the middle of a 2×4 with a spring under it. If you jump on the 2×4, you’re going to compress the spring no matter what side of the pivot you’re standing on. The reason early URT designs were so bad was that they would place the pivot way up high. This meant that the bottom bracket would move an enormous amount as the suspension compressed, and this sucked for two reasons. One, you had a seat height that would change as the suspension compressed. Two, the suspension would only work when you were sitting down. This was advertised as a benefit, but in reality it was horrible. When was the last time you flew into a rock garden sitting down? The reason the Pocket Rocket works so well is that our pivot is right about the bottom bracket – the BB only moves .5″ through the entire stroke of the shock. Its almost impossible to notice as you’re riding along that the BB is moving at all. The suspension works just fine when you’re standing, and seat height variation is negligible.
-7.2 lbs. frame and shock
-30.9 mm seat tube
-44 mm head tube
-68 mm bottom bracket shell
-Shock 6.5″ eye to eye x 1.5″ stroke Fox CTD
-Head tube angle 69 degrees (100mm travel), 67.7 degrees (140mm travel) w/zero stack headset
-Seat tube angle 73 degrees
-Top tube Short 22″ Long 22.75″
-Head tube length 4.5″
-Seat tube length 14.5″
-Bottom bracket height 12.625″ w/2.25″ tires
-Chain stay length 16 to 16.5″
$2100 Frame, shock, derailleur hanger, vinyl decals
In the media:
- Mybikestand Review
- Mentioned in Wired Magazine (please note the price listed is inaccurate)
- Pocket Rocket at NAHBS 2012 from Bikerumor