MikeM,
As if you don't already have enough reasons to go with the Subaru, let me chime in too.
DO IT! You won't be sorry. While I've had problems with my bike and I don't ride much anymore, the motor has been SUPERIOR. From day1, right out-o-the-box, it has been a winner. Tip: get one now; run it about 15-20 min./day; and by time you're ready to build your THING, it'll be broken in and you can--ride that--THING like you stole it!. HAHA
Seriously, though, I can't say enough good about that motor. I'm building a new heavier duty bike from the ground up and that Subaru friction drive will be installed with a chain drive and CVT transmission. But, as a friction drive with a 1-1/8" roller; 100lb commuter bike (with all tools, battery/lighting system, racks, baskets and a 200lb ME, it cruised at 20-22MPH; top speed-27; highest recorded speed (for what it's worth)35 with tailwind,slight decline--FRIGHTENING!!!
Mechanically: Oaky, I'm a little anal about changing oil. Every 2-4 weeks depending on use. But, with such a small amount, a quart goes a long way. Early on, after about 200 or so miles, my engine would bog down on a long hill climb, and even got to pinging. 1st I tried higher octane gas. Worked but sometimes would bog. Next, air filter modification. I removed the paper?? element behind the foam one and it seemed to breath a bit better.
Then I got to messing with timing and valves. Advancing the cam gear +1 or -1 tooth--GARBAGE;ran like poop. Valve lash tinkering--BINGO!!! When I checked the valve gap, the factory settings were waaaaay off! There was NO GAP AT ALL!!! On either valve. Set to the manual specs; some better but not perfect. Being a bit of a 'twiddlefreak' I began messing with the valve lash and found that the engine ran best with the exhaust valve at 1/2 the factory (or .08) and the intake AT the factory setting. Long story short--never a problem again. Seems at the factory setting I was getting a bit of valve float on the exhaust side at WOT. Back to regular 87 oct. gas and no problems anywhere/anytime. Not saying this would work for all motors. You may have to do your own experimentation. But don't be afraid to with this engine. It's easy as pie.
Can't wait to get my next bike in shape and install the SUPERU motor. At only 1.6HP, it's a tried and true motor.
Sorry for the long post; hope--THIS helps.
WC