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bore help!

1626 Views 4 Replies 4 Participants Last post by  69quadracer
I'm trying to figure out 400ex bore info.

If I have a 400ex and bore it from the stock 85mm to 86mm.
is that considered a 416 bore?

and if i have it bored to 87mm.
is that considered 426 bore?
1 - 2 of 5 Posts
Standard bore- 397cc or 85mm
402cc- .040 over or 86mm
406cc- .060 ever or 86.5mm
416cc- .080 over or 87mm
426cc- .120 over or 88mm
440cc- .160 over or 89mm
440cc with an extra 4mm stroke = 460cc
416cc with an extra 4mm stroke = 440cc

Is this correct for a 400ex?
1 - 2 of 5 Posts
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