could it be?

[steven 250sx]

i just got a 1985 tri-z i'm 4th owner , the guy i cought it off said the engine was never opened like even top end could it be? it is a 22 year 2 stroke

[MTS]

very likely, time for a new one before that ol cast piston flys apart.

[steven 250sx]

should i change it *Edited**Edited* it blows? or let it blow then change it

[MTS]

Change it unless you want to do the bottem end at the same time.

[Nick_R_23]

Definately change it first, if it blows you risk breaking cases and bending cranks and all sorts of sh!t you really dont want to happen. Not saying it will happen every time, but as cheap and easy and quick as top ends are on 2 strokes, I wouldnt think twice about changing it on yours.

-Nick :TrikesOwn