Crawl Force is a new company dedicated to rock crawling with UTVs, and its first gear-reduction product is the Crawl Force YXZ1000R Crawl Box two-speed final drive for the Yamaha YXZ1000R and Sport Shift. The Crawl Box installs between the engine and gearbox and replaces the YXZ drive shaft; High range is 1:1, while Low range is a 300-percent reduction at 3:1. We got a chance to experience the Crawl Box on both the manual clutch YXZ and the auto-clutch Sport Shift at King of the Hammers’ Cougar Bluffs, and the Crawl Box units were two of six prototypes.

There will be 35 Crawl Boxes in the first production run (all pre-sold), and the production units have a drain plug, more fluid capacity (Redline Synthetic Heavy Shockproof Gear Oil), thicker dog gears, an enhanced shift fork, and a direct actuator controlled by a solenoid. The beauty of the Crawl Box is that the YXZ performs like stock with five gears in High and five gears in Low, making it perfect for Ultra4 races like King of the Hammers. The Crawl Box works with the GYTR Torque-Assist Gear kit and Rekluse slipper clutch, Tubeworks 70/30 gears, extra clutch packs and lockers.

Crawl Force’s YXZ1000R-4 rock crawls at a slow walking pace in Low range, and seconds later it rips to 60–70 mph in open desert and High.



The YXZ Crawl Box kit comes with the two-speed Crawl Box, electric-shift actuator, mid-drive shaft flywheel coupler, seals and all mounting hardware. Ron Schneider of Crawl Force teamed up with Chris Weismann of Weismann Traction Products to brainstorm Crawl Box and Weismann machines Crawl Box in-house. The customer provides the desired control switch and vent, and Sport Shift requires Tubeworks’ GSE module ($400), which alters the throttle map for Low range.


Internal dog gears, shafts, the shift fork and the mid-drive yoke are CNC-machined from high-grade steel. The Crawl Box starts out as a big block of billet aluminum, and the actuator is also billet aluminum.

Here’s a prototype Crawl Box installed that’s ready for fluids. The Crawl Box works with any YXZ clutch, engine or transmission configuration or mod.



Everyone who has demo’d the Crawl Box has written a check. Anyone who wants to rock crawl or do slow-speed exploration of steep trails, woods, rock gardens and deep mud in the racing YXZ1000R will benefit from the Crawl Box.


Since the transmission is in front of the triple-cylinder engine, Crawl Box installation requires removing the passenger seat, seat mount, passenger-side firewall plastic, mid-drive shaft and clutch cover. Crawl Box is actually three pieces; install the backing plate to the transmission case and then install the Crawl Box housing. The assembled gear pack and flywheel coupler slides into the housing. Run the wiring to the selected toggle switch, and plumb the desired vent to a filter. Installation takes 3.5–4 hours, but Schneider has it down to 1.5 hours.


Starting on page 58, check out the one-off YXZ1000R4 that Crawl Force built; it has Tubeworks’ 70/30 wide-ratio gears, so Low on the Crawl Box slows first gear to a walking pace. We literally loped along at 1–2 mph with no throttle in Low and first. Fifth topped out at 10–11 mph. With standard YXZ gears, fifth tops out around 20 mph. Shift to High, and the YXZ gearbox has the normal top speed and shift points. Gear noise is noticeable when taking off from a standing start in High, but the exhaust soon drowns out gear whine with more speed. Shifting requires a quick stop, and the solenoid reacts instantly.


We know people who fried their clutches trying to rock crawl a stock YXZ1000R, and one sold his afterwards. The Crawl Force YXZ1000R Crawl Box turns the racy Yamaha into a true dual-sport machine that can be fast for desert and dunes and a cruiser for trails, mud or rock crawling. It will even work with Yamaha’s and Weller Racing’s turbo kits. It’s pricey at $4999 (plus $400 for Sport Shift), but, as we said, everyone who has tried it ended up buying it. Crawl Force is also looking at gear-reduction solutions for Talons and CVT-driven UTVs.


RATING: ★★★★

PRICE: $4999; $5399, Sport Shift

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