Steam or oil smoke? Oil smoke would be fine, steam would be a concern. If it runs at normal temperature, there aren't bubbles coming up in the coolant filler neck and it doesn't lose coolant I probably wouldn't be overly concerned.
Perth, Western Oz 1975 RE5M x 2 02 Beemer R1100S mature conveyance Some dirt bikes for fun! Wish list: Just about everything in Jay Leno's garage
Kim Are you loosing water through the pressure release overflow pipe ? ( Filler neck pipe that runs under fuel tank and exits under battery/swinging arm) If your engine is pressurizing you maybe loosing water this way without noticing as it steams out under the bike , I had this some years ago for a few thousand miles and kept topping up coolant until the unit failed due to cracked housing, Spark plug was always very clean as was the unit when I spit it ( Steam cleaned ) I hope this is not the case with your unit. Rog
Now Bikes RE 5 M,(UK )Blue 1974 RE 5 M (UK) X 6 H/D XR1200 X1 Sports RE 5 A (UK) Black 1976 Norton Rotary Classic 1988, Norton IP2 1986