Not uncommon. In my experience, typically, the seat strut is not cut off due to the use of a larger seat, it has been removed due to the use an inboard clutch. Lots of guys are doing that very same thing when utilizing the Euro type chassis in the new LO206 and four stroke motors. Seems easier to remove the seat strut than to use an entire jackshaft assembly. Might get with the previous owners to verify this.
Can’t say either way whether the handling is affected becuse I have no first hand experience with it, but I know a couple of guys which are now using the chassis minus the original seat struts, in Rotax and haven’t heard of any complaints.
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