Monkey Ride: Neil’s Rohloff/Belt Drive-Equipped Moots 29er

In preparation for the 2008 North American Handbuild Bicycle show in Portland, OR, Neil worked with Moots on this custom 29'er soft-tail as a test bed for the then-recently-launched Gates Carbon Drive belt system. The previous fall, Gates released the belt system, which promised improved durability with comparable efficiency to the tried and proven metal chain. In terms of improving overall drivetrain reliability, the new Gates belt system looked like a great complement to the highly durable Rohloff SPEEDHUB 500/14.

After the show, Neil planned to ride the bike around the trails in the East Bay hills near the Cycle Monkey office. Since most of the legal local riding is fire road and smooth single track, Neil opted for a longer top tube for a more stretched out, racier setup. This was Neil's first 29'er and, coming from a background of riding long-travel full suspension bikes, he chose the Moots’ Mooto X YBB titanium soft-tail frame as a compromise to a hardtail. With 28.6mm (1 1/8") of pivot-less travel, this frame seemed to offer the best characteristics of a hardtail while still having a bit of give. The micro-suspension relies on the inherent flexibility of titanium to allow the chain stays to bend slightly and compress the coil spring located in the seat stay yoke.

Since belts can’t be disconnected like standard bike chains, frames that use a belt drive require a split somewhere in the drive side of the rear triangle so that the belt can be installed. Moots came up with a simple modification to their YBB seatstay yoke that allows the stays to fully separate from the soft-tail’s suspension plunger. Instead of using a collar with a single clamp, they added a second clamp on the opposite side and split the collar into two pieces, much like a stem with removable face plate.

For the wheelset, the Rohloff SPEEDHUB 500/14 rear hub and Chris King 15mm through axle front hub were laced to white Stan's NoTubes ZTR Flow rims for a sturdy, trail-style build. Titanium spokes and allow nipples offset the additional weight of the Flow rim and keep the wheels fairly light.

Outside of the frame, Rohloff SPEEDHUB, and headset, this bike has seen various parts over the past six years. The current setup includes an array of titanium parts that complement the frame: Moots stem, handlebar, and seatpost, King Kage water bottle cages, Chris King headset, generic seat collar, and USA Brand spokes. An Ergon SM3-L saddle and ESI foam grips ensure comfort at the bike's contact points, and Rock Shox’s 100mm-travel SID fork handles suspension duties up front. A pair of white Groovy Cycle Works Hotrod cranks turns the sprockets, and we used Cycle Monkey’s own Monkey Bone rear brake adapter to secure the Rohloff hub to the frame.

The frame has performed very well over the past six years. As expected, the micro suspension takes the edge off the bumps - especially small, high-speed stutter bumps - and has proven to be more comfortable than a full hardtail. It still offers the solid pedaling and acceleration performance that you expect from a hardtail. The stretched-out rider position is comfortable for general XC riding, and the long wheel base is very stable on high speed descents. The bike feels right at home on the fireroads and wider, smoother single track readily available in the East Bay.

Durability of the belt system has been very good, with no replacement parts needed in two years of regular off road riding using the current Center Track parts. The system has been very low maintenance with low friction that feels comparable to a chain and no skipping during hard efforts. The only issue we have run across is that the belts tend to squeak in dry, dusty conditions, which can be irritating on long, slow climbs. Gates recommends using CRC Silicone spray on the belts to quiet them. This seems to last for 50-60 miles before needing to be reapplied. We have recently begun using Rohloff's biodegradable chain lube, which seems to last much longer.

Overall, Neil's Moots project has given us enough confidence in the Rohloff and belt drive combo to recommend it to our customers. This has lead to a number of recent belt drive bike builds and frame conversions that we have done recently. We feel that the Gates belt system is a good compliment to the performance and durability of the SPEEDHUB. Contact us to ask how we can do a belt drive/Rohloff setup for you!

Build details:

·  Frame: Moots Mooto X YBB Soft Tail

·  Fork: Rock Shox SID 100mm travel 29”

·  Headset: Chris King Titanium

·  Stem: Moots Titanium

·  Handlebar: Moots Titanium 

·  Shifter: Rohloff

·  Grips: ESI Latex Foam

·  Seatpost: Moots Titanium

·  Saddle: Ergon SM3-L

·  Seat Clamp: Titanium

·  Front Hub: Chris King 15mm through axle

·  Rear hub: Rohloff SPEEDHUB 500/14

·  Spokes: USA Brand Titanium

·  Nipples: Sapim Alloy

·  Rims: Stan’s No Tubes ZTR Flow 29”

·  Tires: Specialized Fastrack

·  Cranks: Groovy Cycleworks Hot Rod Cranks

·  Bottom Bracket: Chris King

·  Chainring: Gates Carbon Drive Center Track

·  Pedals: Shimano M959 SPD

·  Chain: Gates Carbon Drive Center Track Belt Drive

·  Brakes & Levers: Magura Marta