I played the arcade version back in 1976 and the gameplay and physics were awesome .. I spent about $10 trying to master it.
When I got the home console at discount in 1979 ($20) , I was disappointed in the weird physics .. cycle hangs low, high, low for the first few busses. Later busses show more realistic jumps.
What surprises me is that the engineering is Atari but the stunt cycle chip is made by General Instruments in 1977. So the GI engineers saw the arcade game, talked to Atari and made the chip and sold Ataris game to them. They must have been working together. And the Sears version which has the pong games must have used a GI Pong chip to make the unit electrically compatible. The Atari version of SC has a volume (low / high) switch instead of the PONG / SC switch. Also has a plastic insert in the side where the Sears Pong controllers plug in.
Inside the Atari is the same circuit board which has connections to add the four Pong controller ports ... my plan is to install a port there to allow the Atari SC to function as a throttle controller for both the Atari 2600 proto and the Vectrex version of SC which is due to be released soon. Also I plan to use it as a throttle controller for my arcade Asteroids Cocktail which has the Lunar Lander arcade ROM built in. That will allow for analog thrust instead of digital button thrust!
In Radio Electronics magazine, January 1979, theres an article about building the SC with input from the GI engineers. All parts including the circuit and the AY-3-8760 SC chip were available for purchase for $61.75 from an outfit in Mesa, AZ which sadly does not exist anymore. Of course the spring loaded pot was not available then. I imagine that by Jan 1979, GI was unloading these chips ..
I havent looked at the 2600 proto of SC in years .. I would love to see / play the arcade version again!!