Be careful when trying to start the engine for the first time, unless you've done it before, as you don't really know what to expect. When I tried to start mine for the first time within the first 3 or 4 pulls I had snapped the plastic throttle lever. I think I managed this by pulling the starting cord at such an angle that I managed to pull across the throttle linkage snapping the lever. As you can imagine the air was blue.
My first reaction after the swearing had stopped was to look online to see if the part was available separately, it is, and costs £3.95. Not cheap for what it is, but more importantly I would have had to wait 3-4 days to get one.
Rather than wait, when all I wanted to do was get the engine started, I thought I would try to make one. I made it out of a fencing bracket, and although not pretty it seems to do the job. So much so that I don't see any need to change it back to a plastic one.
The only issue I found was that behind the lever is a serrated locking washer that stops the lever from moving and not opening the throttle. This washer obviously locked the plastic lever in place very well but does not dig into the metal lever as well meaning the nut has to be done up extra tight.
Broken throttle lever.
My repair.