Algodoo

I added a spring-loaded idler which works great as a chain tensioner!

Excellent tutorial!

Thanks for the suggestion.

Nice tutorial! The chain generator you made way back looks better though

Is there any way to make a scripted 2:1 transmission without much variation in its angle? I just remembered a scene I have lying around on my scenes folder just because the timing gears slip after some time. With that, we may be able to reach 4 stroke, 7000 RPM engines now.

Maybe use two circles with hinges. In one circle postStep: angle = scene.my.angle. In the other circle postStep: scene.my.angle = 2.0 * angle.

Another way might be to do something similar to Transmission Hinge

Maybe the transmission hinge is what I wanted. I tried doing the other idea before but it didn't work properly. I have a couple of ideas using the new engine's angle spawner though

You can set the bendTarget of a hinge to the angle of one of the connected bodies. The angle may or may not need to be inversed. That way, you have a reliable 2:1 gear ratio.

The same thing I did in my single cylinder engine. The camshaft is always synchronised with the crank http://www.algodoo.com/algobox/details.php?id=158419