These engines are great, they might be a bit heavy, but their powerful and strong and last for ages.
The long thing is a tuned pipe and gives you more power for more RPM or to swing a bigger prop.
If the engine is new you might think its a pig to run, but it needs a long run in period, dont worry about running it rich, it just takes ages for it to settle down, espicialy on bottom end, but once it is, they are lovery.