hi there :)
I made some edits .. but;
You might have to reevaluate what you tried up to now.
As it looks, you only applied friction on the back wheel, and probably been looking at your running application, comparing effects with effects from your front wheel.
Not sure if thats the case, but I did in first instance.
It gives a total wrong picture of whats wrong/not working propperly.
So I added friction to the front wheel too, because, as you move forward, pushed by the rear wheel, the front wheel drags itself in circles over the ground, by friction.
Seeing as you are on top (bike > ground), I supose whats below deserves a bit more friction as it carries all the weight.
I believe this results in a more propper mechanic.