B.C. Rider
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So doing a beefed out 48cc CD and i was curious if anyone knows of a 40mm piston other then the stock one that is compatable with them?
Piston options
- Thread starter B.C. Rider
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607Underground
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You'd have to measure with a caliper and take many notes.
Total piston hight crown to skirt
Skirt to center of wrist
crown to center of wrist
wrist pin diameter
Bore and stroke are just a fraction of the equation because if the wrist is too low is doesn't matter if it's otherwise the same exact piston you'll hit the head. Likewise if the wrist is too high, or the piston skirt too long, you'll end up bombing the skirt on the rod geometry.
You can usually drill for a wrist pin one mm larger, or drill an imperial to the nearest larger metric and vice versa and get away with it "safely"... but it's not a recommended practice because it's not entirely safe.
If any one measurement doesn't match up just don't risk a swap (obvious signs of galling and wear are an exception but the bore should be looked at as well in that case)
Total piston hight crown to skirt
Skirt to center of wrist
crown to center of wrist
wrist pin diameter
Bore and stroke are just a fraction of the equation because if the wrist is too low is doesn't matter if it's otherwise the same exact piston you'll hit the head. Likewise if the wrist is too high, or the piston skirt too long, you'll end up bombing the skirt on the rod geometry.
You can usually drill for a wrist pin one mm larger, or drill an imperial to the nearest larger metric and vice versa and get away with it "safely"... but it's not a recommended practice because it's not entirely safe.
If any one measurement doesn't match up just don't risk a swap (obvious signs of galling and wear are an exception but the bore should be looked at as well in that case)
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