Story By: Dan Reincheld & ATV Source
Photos By: ATV Source & Dan Reincheld

The Mighty Arctic Cat Thundercat 1000

The new 1000cc two headed beast.

Arctic Cat calls their new H2 Thundercat 1000 ATV a two-headed monster, and they are correct about it being a monster. Monstrous power, thunderous torque, and super quick throttle response are the signature features of this new top of the line Arctic Cat quad.

The manufacturer claims it is the fastest accelerating ATV on the market, sport or utility, and at this time, we believe it. One quick punch of the throttle lever on the Thundercat was convincing that they were right. Throttle response is unbelievably sharp and fast, and in most normal riding conditions 1/4 throttle will yield enough power to get the job done, and quickly.

The heart of the Thundercat

The heart of the beast is a 90-degree twin cylinder, hemispherical combustion chamber, single overhead cam, four valves per cylinder EFI brute. Displacing 950 cc, it is the current King of the Big Bores. Operating two valves per cam lobe with forked rocker arms, the designers developed it for maximum torque, and claim 188 ft. lb. at the crankshaft. When questioned about the huge torque figure (more in fact, than a 4 cylinder, 2.7 Liter DOHC truck engine), company representatives assured us of the accuracy of the figure. Arctic Cat will not release hp ratings, but from our ride time on the Thundercat, we can say it is considerably higher than other ATVs in its class. Of course, at the time of this writing, there is no other quad in its class (although there are rumors that both Polaris and Can-Am are working on one). Some have questioned whether Arctic Cat used the Kawasaki 650 cc twin bored out, but it is not a Kawi engine. This motor is new from the gear case up, and totally an Arctic Cat design.

The chassis design of the Thundercat is also new. It utilizes the same basic frame design as the H1 650 but is stretched by 2.5 inches, to better handle the quick acceleration and tremendous torque output of the Thundercat engine, yielding a 52.5" wheelbase. The added length was also used to help limit the tendency of that much power in a 716 pound quad to raise the front end on hard accelerations. Suspension components were redesigned to maintain stability without the use of an anti-sway bar, to allow full travel of the fully independent suspension. They succeeded admirably as body sway is minimal except in very hard cornering, and the body stays nearly level even in off-camber situations. Some front-end push was noted in very loose material conditions, but we suspect this can be minimized by adjustment of the 5-way pre-load shocks and tire pressures according to the rider's weight and riding style. The new Maxxis 4-Speed(R) radial tires in 25x8x12 and 25x10x12 sizes on stylish cast aluminum wheels round out the suspension package. The tires were specifically designed for the Thundercat by Maxxis, to yield stiffer sidewalls, which resulted in better handling characteristics over standard off-the-shelf 4-Speed(R) tires.

The full functioning of the IRS components made it difficult to power slide, as the rear tires bite too well to get the rear to slide, a plus in some riding conditions. The Arctic Cat standard of 10" suspension travel has been maintained in the Thundercat, but it sits an inch lower with 11" of ground clearance for better handling. When mounting the Thundercat the suspension squats about 2" or so (depending on rider weight and load weight). This helps to "dial-in" the suspension for each rider and loading condition. When unloaded the quad has 13" of ground clearance. The seat design was changed to allow a lower rider position, thus lowering center of gravity and improving handling. Arctic Cat calls this sitting "in" the quad rather than "on" it. An optional anti-sway bar will be available from dealers for those who require maximum stability and can afford to give up some rear suspension travel and rear wheel traction. This might be the ideal set-up for aggressive trail riding.

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