| All valid points, Henry. Depends on the confidence level of the rider, I think. I bought a 600cc Yamaha, sit up and beg variety, the day after passing my direct access course, so had only ridden a 125 and only for 5 days, nothing prior to that. My first reaction was '**** it's fast', but that was the only thing that felt really different, because other than the weight and the speed, the riding position and everything I'd learned on the Yamaha 125 was the same.
I would always recommend buying a first bike that mirrors the riding position of the bike you learn on, whether it be sports or sit up and beg. That's one less thing to think about. Passing your test gives you a great feeling of confidence. That confidence is easily dented if you immediately throw too many differences into the equation.
Generally, I'd say a 600 isn't too big to move up to immediately. Buying a bike that makes her want to get out on it as much as possible is key. Enthusiasm can overcome reams of reservations. Buying a bike that doesn't feel right, eg feet not flat on the floor, tank too wide, handle bars too much of a reach, all of those things add to the discomfort a new rider has and could be enough to discourage regular outings.
Hope that's helpful.
Best of luck
Ruth  | 
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