Yes I would think a 24 would be ok with the alloy pulley on the motor as the motor is a distance away from the cutting part of the deck just as long as it doesn't get covered with grass.
On a side note ,I got a chance to look at the Honda Line Trimmer UMK 425U ,pulled the carby down, blew some compressed air at it ,dismantled the original fuel filter and gave it a clean but when I connected a hose to the filter and blew air down it, it just seemed a little restricted ,so I took a filter out of another snipper that was less restricted ,then changed the fuel hoses $1.70 a meter ,replaced the pump diaphragm in the carby with one from an old 2 stroke carby that was a acetate blue diaphragm , and now runs like new.
I can get a new red engine cover for $20. or just find another Honda snipper for a cover.
Also this snipper would not rev out properly until I changed the fuel hoses and the filter even though there weren't any obvious defects and the primer does blow a few air bubbles down the fuel hose back to the tank if you push the primer fast.
