The two cycle engines are -air cooled - and will be damaged by heat ,unless you get them into the air ,were they should be broken in - In the air !
Run the engine rich ,to prevent heat build up ,if its on a stand
Run 20% oil , with castor oil ,on a stand

If you go to the forums - scroll down to -Glo engines ,scroll down to - Tips and technics- then go to - Things i have learned to keep my glo planes flying reliably over the years
You will have my own complete explination on how to run and fly two cycle glo engines and aircraft in the 40 and 60 size airframes
I do every aspect of flying this style airframe ,for over 20 years ,with an Outstanding track record ,to look back on
Build battey packs ( nicads ) and do all my engine work and air frame building ,at times from plans and a pile of balsa wood
My galley ,on the left of this post ,will have pictures of some of the best two cycle aircraft and power plants from the last 20 years
Many of my collection have hundreds of flights on them
i have thousands of flights on a 60 size stik ,that is very very modified , to my liking
The 20 size stik ( a kit ) was the first kit i built , the 40 size stik ,is a plane i have redone three times , over the years and the second plane - i ever flew ,and they are still going strong
Constant maintenance and inspection is the key ,to keeping the airframes in tip top condition
Building it right ,after years of hands on experience ,then working out the BUGS the first 10 flights of a new plane , is the key to long term success
The jouney is all about the FUN , of getting it right

Enjoy