stuffed crank

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stuffed crank, is basicly the same as a regular shaft but the fill the cutouts with resin, gives you more compression due to the resin filled areas reduce the volume of the crankcase
http://www.davesmotors.com/s.nl/c.885035/n.1/it.A/id.1292/.f

a non- stuffed crank basicly cut the same as a stuffed and vice versa but no resin packed in the cutouts, more crankcase volume less compression, how much? could not say
http://www.davesmotors.com/s.nl/c.885035/n.1/it.A/id.1289/.f

stroker just means the crank conrod is 1-4mm longer which you get the long stroke engine term,

you asked a question that would compare a stuffed to a stroker, which you usually get a stuffed stroker in some of the engines out there
like 30.5 engine, the conrod is already 2mm longer then stock, and the cranks usually are stuffed on most of the 30.5 engines,
even the KM 30.5 comes with a 2mm stuffed stroker engine, with out the 2mm longer con rod the engine would be a 29cc i believe maybe a 28.5cc
 
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A stuffed crank incresses crank case pressure not compresion. A +2mm will do both. Incressing crank case pressure is like turning the boost up on a turbo motor. You stuff more fuel air into the cyl which in turn makes more power.
 
bhilly82 said:
A stuffed crank incresses crank case pressure not compresion. A +2mm will do both. Incressing crank case pressure is like turning the boost up on a turbo motor. You stuff more fuel air into the cyl which in turn makes more power.
Click to expand...
pressure? thats the same as compression the engine it self is sealed other then the inlet and outlet ports, and fuel does go below the piston,so as daves put it the primary compression, so in order to build pressure you have to compress it,
 
chitown joe said:
pressure? thats the same as compression the engine it self is sealed other then the inlet and outlet ports, and fuel does go below the piston,so as daves put it the primary compression, so in order to build pressure you have to compress it,
Click to expand...

The way you made it sound was it increased compresion in the cyl ie cr. but were just compairing apples to apples here. The way I look at it compresion is for the combustion side pressure for the intake side. But no biggie.
 
chitown joe said:
stuffed crank, is basicly the same as a regular shaft but the fill the cutouts with resin, gives you more compression due to the resin filled areas reduce the volume of the crankcase
http://www.davesmotors.com/s.nl/c.885035/n.1/it.A/id.1292/.f

a non- stuffed crank basicly cut the same as a stuffed and vice versa but no resin packed in the cutouts, more crankcase volume less compression, how much? could not say
http://www.davesmotors.com/s.nl/c.885035/n.1/it.A/id.1289/.f

stroker just means the crank conrod is 1-4mm longer which you get the long stroke engine term,

you asked a question that would compare a stuffed to a stroker, which you usually get a stuffed stroker in some of the engines out there
like 30.5 engine, the conrod is already 2mm longer then stock, and the cranks usually are stuffed on most of the 30.5 engines,
even the KM 30.5 comes with a 2mm stuffed stroker engine, with out the 2mm longer con rod the engine would be a 29cc i believe maybe a 28.5cc
Click to expand...

Actually Joe the conrod isnt where the stroke comes from, it comes from the offset of the rod pin in relationship to the centerline of the crank. Moving the rod pin farther away from the centerline makes a longer stroke. Either rod length then needs to be shortened or the cylinder chamber needs to be machined to allow the piston to travel farther up the cylinder without hitting the combustion area.

bhilly82 said:
A stuffed crank incresses crank case pressure not compresion. A +2mm will do both. Increasing crank case pressure is like turning the boost up on a turbo motor. You stuff more fuel air into the cyl which in turn makes more power.
Click to expand...

Actually what a "stuffed crank" does is increases PRIMARY compression on a 2 stroke engine, which will effectively increase secondary compression (cylinder).
 
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