# Displacement: .025 overbore = how many cc's?

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PO said the bike I bought is .025 over. How many cc's does that increase the displacement?

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0.025", 0.025mm, or 0.25mm?

(pi) * r² * h = v

pi = 3.14159

r = cylinder radius

h = height of the cylinder

v = volume

Since you're (probably) dealing with millimeters and need to get centimeters, divide the answer by 1000.

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.025 would be inches, I'm pretty sure. That is somewhere around 0.64 mm.

According to a quick calculation, I get an increase of from 644 to 652cc's for an XR650L.

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Yeah I was double checking that measurement. The PO's said "bored to 0.025".

I'm getting 599 cc. I used 48.82 for my radius, by taking 97mm stock bore diameter adding the.64mm and dividing by 2. Stroke being 80mm.

3.14 x 48.82 (sq) x 80= (X)/1000 to convert to cc's.

Edited by mikesbaron

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If you are talking about a XR600R

25mm overbore (97.25mm bore) will give you a 594cc displacement

.025" overbore (97.64mm bore) will give you a 599cc displacement

Edited by XR650LANE

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Yep...so guess that's a confirmation. .025 isn't anything big after all. Thanks.

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