Half a croissant, on a plate, with a sign in front of it saying '50c'
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Offset Crank

Offset the crank to prevent side-loading during expansion
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As the piston goes down during expansion, the angle of the connecting rod creates a reaction force of the piston against the cylinder wall. On older engines you can tell which way the engine was spinning because the walls become more worn from the expansion reaction than from the compression reaction. Proposed is an crankshaft off center from the center of piston travel. A compromise would be made to balance the advantages of reducing this side-loading while not interfering too much with TDC dwell characteristics and with compression-stage side-loading.
kevinthenerd, Jun 14 2012

[link]






       already done.
WcW, Jun 14 2012
  

       I was pretty sure we'd already done this one at least twice, because I remember being embroiled in an intense discussion involving side-loading and unveven cylinder wall wear. I'm also reasonably certain that real-world attempts to bake this have been made.   

       I didn't say anything at first because, well, I was feeling too lazy to go searching for links to back up my claims. Thanks to mob rule, I now feel comfortable to make groundless accusations. Thanks [WcW].
Alterother, Jun 15 2012
  

       Piston slap has been an issue since the first IC engines were designed. Take away the crosshead and slide (reducing mass, thus allowing higher revs) and the piston starts to oscillate round the gudgeon pin.   

       Sorry, you're about a century late with this one ...
8th of 7, Jun 15 2012
  

       //done this// most recently was yours truly's "Squiggle Cylinder" which totally eliminates downstroke sideloading, using a "Donut Piston" where the contact area is a circle instead of a cylinder.   

       But there are existing designs which offset the cylinder angle.
FlyingToaster, Jun 16 2012
  

       I thought this was just going to be me, standing a little to one side.
not_morrison_rm, Jun 16 2012
  

       or slightly tipped over.
FlyingToaster, Jun 16 2012
  
      
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