Harrison Research Wildcat and Bobcat Mini Bike Information.
I buy and collect minibikes. 12/1/18. Email: cfh@provide.net

Overall Harrison Research Inc. History and Info.

    Here in Michigan, the home of Ruttman and Heald and Harrison and Little Indian minibikes, the Harrison Wildcat (and Bobcat) minibike has a strong following. Elsewhere in the country, I'm not so sure. But here in Michigan, Harrison really has a home. It could be because the Harrison company was located in Utica Michigan (a suburb of Detroit). But it could also be the population of this mini bike is pretty strong, due to its location.

    The Harrison Wildcat (and Bobcat, the kit form of the bike) was a "fat tire" minibike with a long 38" wheelbase. Though it used standard 6" wheels (like many other minibikes of the era), the tires were wide (15 x 6.00 x 6). Hence adults like to ride this bike as it seemed more inline with their size and age. Also the ride was quite stable, even at speed. Hence today the Harrison Wildcat is a favorite of mini bike drag racers.

The 1969 Harrison ad sporting a Briggs 5hp motor.

    Harrison started out about 1969 with the Wildcat and the Bobcat (the same bike but in kit form.) Almost immediately there were some legal issues with Ruttman (Dearborn MI). Ruttman felt that the Harrison copied their minibike design (specifically the Ruttman Pacmule.) After deciding that lawsuites were no good for either company, Harrison and Ruttman came to an agreement... Harrison would continue to sell the Wildcat/Bobcat, but Ruttman would make the frame. Hence the first year Harrison bikes are slightly different than the 1970 and later models (made by Ruttman). You can always tell a Ruttman-made Harrison, because of the way the two top tubes meet the fork tube.

The 1970 Harrison ad sporting a Tecumseh 4hp motor.

    The 1969 Harrison came with a 5hp Brigg &Stratton motor. By 1970 this changed to a Tecumseh (mostly HS40, though the HS50 was available as an option later.) Speaking of options, there were quite a few options available for the Harrison:
    • Seat (18" or 24").
    • Jackshaft (aka Midshaft).
    • Jackshaft puck brake (in addition to the rear drum brake).
    • Clutch brake (on the Bobcat)
    • Salsbury torque converter or Max-torque clutch.
    • Chain idler (chain tensioner, for use without jackshaft).
    • HS50 Tecumseh 5hp motor (about 1972).
    • Remote fuel tank (18" seat required so the tank would fit on the frame).
    • Front suspension.
    • Front ski for snow use.
    • Light kit.

    In addition there were several models of Wildcat/Bobcat (varied through the years):

    • Wildcat Model 100: Max-torque clutch, chain tensioner, 4hp Tecumseh HS40 engine, painted fenders and chain guard, rear drum brake, 24" seat for two, red or blue, $239.95.
    • Wildcat Model 100 Deluxe: Exactly the same as the Model 100 but fenders and chain guard are chrome and frame is painted orange or yellow, $249.95.
    • Wildcat Model 300: Same as the model 100 except has a Salsbury Torque Converter (instead of a Max-Torque clutch.)
    • Wildcat Model 300 Deluse: Same as the model 100 deluxe except has a Salsbury Torque Converter (instead of a Max-Torque clutch.)
    • Wildcat Model 400: Same as the model 300 but with 24" seat.
    • Wildcat Model 500: Same as the model 400 except has a Salsbury Torque Converter and 5hp Tecumseh motor and remote gas tank with 18" seat (1972).
    • Bobcat Scrambler kit. This uses a clutch brake (instead of a rear drum brake), $199.95.

    Here's a Harrison catalog in PDF format from about 1970.

    Today, the Harrison Wildcat/Bobcat have taken on new life, some 40 years later. Besides the Detroit drag racing scene (which likes the Harrison), others like the bike for long rides. It is a comfortable ride. But they have taken on some modifications like installing a Tecumseh 10hp motor (top speeds in excess of 50 mph.)

Adding Springer Front Forks to the Harrison.
    One of the things I don't like about the Harrison is the lack of any suspension. Though Harrison did make a front suspension option, it is rarely seen. Fortunately it is easy to add a springer front end to the Harrision Wildcat. Here's the proceedure...

    First you'll need some parts. OMB warehouse sells a front fork spring and cup kit, you will need that. You will also need two one foot sections of 11/16" solid steel rod. The original front end will need to be cut at 2" below the lower fork triangle. And the lower sections shortened to 7" long. Note these lengths will make the front end rise up an inch or two. This increases fork rake slightly, and makes the bike handle better. Also the front fender mount must be cut off the front fork.

Parts needed and cuts made to the Harrison Wildcat front end to add springs.

    Next the 11/16" one foot long steel rod sections need to be hammered into the lower cut front fork section. Hammer it all the way till it "bottoms out". Then the cups need to be welded to the fork sections, as seen below.

    The 11/16" steel rods should move freely inside the original Harrision top fork tubes. But the welded seems inside the tubes may need to be shaved to get a smooth action. Ideally this is done with an 11/16" drill bit or something similar. Put a little grease on the steel rod and assembly. I drill two 1/4" holes in the lower triangle section so I could attach the front fender using 1" spacers. We're now ready to ride!

Here's a Harrison Wildcat my friend owns. He really did a nice job with many modifications.
Check out the aluminum drum gas tank and custom exhaust and front spring fork!

Here's my Harrison Wildcat with a Tecumseh HS50 motor and torque converter. Uses
a 16 tooth sprocket on the torque converter through the #35 chain to the 72 tooth original
rear sprocket. Top speed 35mph. First picture is how I got the bike off Craigs List.

Here's my Harrison Wildcat with a Tecumseh 10hp motor. This thing flys! But frankly it's
probably too fast and too quick. I actually prefer the 5hp model above. The jackshaft sprocket
on this bike is 20 tooth feeding the original 72 tooth rear sprocket. Top speed 50mph+
This bike has original fenders, see how they are slightly different than the red bike above?