Big Dog Mastiff




Make Model.

Big Dog Mastiff




Four stroke, 45° V-Twin, OHV, 2 valves per cylinder.


1916 cc / 117 cu-in
Bore x Stroke 104.8 x 111.1 mm / 4 x 4 ⅜"
Compression Ratio 9.6:1
Cooling System Air cooled


EFI or Super G carburetor


Electronic single fire




6 Speed

Final Drive

Frame Standard downtube,  4" Backbone
Rake 39°

Front Suspension

Ĝ41 mm Telescopic fork

Rear Suspension

Hidden shocks

Front Brakes

Single disc PM, 4 piston caliper, differential bore

Rear Brakes

Single disc PM, 4 piston caliper

Front Tyre

MH120/70-21, Avon

Rear Tyre

250/40 -18, Avon
Seat Height 622.3 mm  /  24.2 in

Dry Weight

308 kg  /  680 lbs

Fuel Capacity 

17.4 L / 4.6 US gal

While the Mutt and Pitbull represent new blood in Big Dog's Pro Street line, the Mastiff retains the bread-and-butter styling cues that got BDM where they are today.

The 8.5-foot long cruiser has a six-inch oversized backbone stretch with stock downtubes, the same frame geometry as last year. The A-Frame swingarm has been redesigned with the intentions of smoothing out the ride and still supports a 300mm meaty rear, the healthiest backside amongst the Pro Streeters.

An adjustable hidden shock suspension should assist the swingarm in making the Mastiff rider-friendly. Rider comfort will also benefit from the under-molded rubber grips and pegs that BDM claims to reduce vibration felt in the hands and feet. Sweet-looking rubber-mounted low-rise chrome handlebars sweep back for an arms-forward, upright riding position, assisted by a low 24.25-inch seat height. The 41 mm telescopic fork is set at a 39 degree rake angle with an extra 3 degrees provided by the tree rake, time-tested dimensions for a Big Dog bike.

The motorcycle has color matching fenders, gas and oil tanks that are complemented by plenty of requisite custom chrome. One of the best moves BDM has made for '08 is allowing riders to choose the fuel system for the Mastiff, EFI or a Super G Carb. Buyers always like to feel empowered by having a say in their build.

And though the body of the Mastiff doesn't differ much from last year's model, customers can always individualize their bikes by choosing one of seven base colors and topping it off with one of the 70 graphic packages Big Dog offers. And you don't have to stop there. Big Radius or Mean Mother exhausts are other customization options that can help set your bike apart. Custom seats, sissy bars, touring bags and more are also on the list of BDM aftermarket accessories readily available to help you pimp your ride.