520sx cylinder and piston on a 2000 400sx to make it a 450? *DELETED*

Post deleted by MotoGyro

seems to me that putting a 520sx cylinder and piston on a 2000 400sx to make it a 520 :cry:


Well, it won't make it s 520.

THe new 450 and 525 share the same bore, but the strokes are different.

The 400 and 520 though - I dunno. Assuming everything lines up, and the strokes are the same, yeah, it should make it a 520. If the strokes are different (520@ like 72mm, 400@ say 60mm) it wouldn't work at all would it? You'd have to lengthen the crank, otherwise you'd have a, say 1.75:1 compression ratio with the longer cylinder.

seems to me that putting a 520sx cylinder and piston on a 2000 400sx to make it a 520 :cry:

Bore and stroke

400SX 89mm X 64mm

450SX 95 X 63,4

520/525SX 95 X 72

400EXC 89 X 64

450EXC 89 X 72

520/525EXC 95 X 72

Note the diffrens on 450SX and 450EXC

A 95mm piston in a 400 will give you 453cc.


You CANNOT drop a 520/525 piston in a 400 it will not work. The deck hight of the piston will be too low.

The 520/525 cylinder will fit with a special made wiseco piston that is avalible through selected dealers.

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