Quick question... anyone able to suggest engines (1 cyl 4 strokes

) which might fit into an NSR125 chassis?
It is a perimeter frame so as long as the head will fit between the rails most other things can be worked around, anyone got engines lying around they could wave a ruler across?
Cheers in advance(!)
Smudge

edited to add, electric start is good as it's aimed at swmbo who doesn't do kickstarting...
