Easiest build possible

[happycheapskate]

I agree. Dax Friction Drive is where it's at for easy entry level bike. The dax will work off-road (jeep roads, country roads). Use whatever front tire you like (full knobby even), and cheap beach cruiser tires in the back, something with either linked knobs, a flat center belt, or "semi-slick" (knobs on sides, belt in middle). Be careful about riding on park roads. On the street they probably won't care, but on trails, you should check the rules.

Message me if you want help.

I just got an engine for $50, and the Dax kit is $150 shipped. You can get rigid mtn bikes for $50 on auctions or online.

http://www.motoredbikes.com/showthread.php?41776-43cc-Viper-engines-on-eBay-for-cheap

If you want an easy build I'd suggest the DAX friction drive kit with the Super Titan Engine. With the DAX Engine Bracket you can simply disengage the roller by loosening the lever & lifting the bracket/roller off the tire & securing the whole bracket/roller in place by simply tightening the lever so you can pedal. Whole installation should only take 1 hour at the most even for the most marginally mechanically inclined.

 

[Otero]

I have a dax & a staton, both easy to set up. Even though
it's not a big semi-slick tire, I've had good luck & longer wear
with a 1.75" Bell cruiser tire. Instead of 55 psi as I was told
was best pressure, I've learned that 40 psi let's you press
the roller further down on the tire to make a stronger contact.