I must have read that 725cc in one of the articles I found on lawnmower racing.
Could have been for ARMA.
Do they measure bore and stroke to determine what displacement/HP you are using? If thats the case I would guess boring or stroking is not allowed? [
Very new to this, trying to get the engine figured out first.
One other thing, rules say "Crankshaft must be in original orientation and clearance hole in the frame"
Since my tractor had a single cylinder Briggs with the hole ofset from center, can the hole be extended so the v-twin can be mounted centered in the frame side to side?
Thanks
Are you building to ARMA rules or USLMRA?
You stated a BP, which is a USLMRA class.
Must be in Original hole means just that, no you can't modify that hole.
Also you have to have a license to run BP in USLMRA.
The reason for that is because if your new you shouldn't be on a BP yet, those things are wild and take some experiance to drive!