Well, as far as I know the cable I measured was an original. Given that, maybe your best plan is either to remove and measure your exhaust lifter cable and duplicate it, or make a cable to my outer cable dimension with the inner unsoldered and a little longer on the "suck it and see''principle. An observation here, though. The Spares Co. have, in the past, made front brake cables too short, so that the cable and brake arm form an angle greater than 90° by the time the brakes contact the drum. So I'm sorry if you've got a bum steer from me, but the cable I measured was a Twin clutch animal. I think if my outer cable dimension suits, and doesn't flap in the breeze, it may give the cable an easier life because of the greater arc.