It’s a funny one in the world of Paramotoring. It seems that Most people (that I have spoken too) think around 100ish hours is the time to get rid and buy a new one, however they will go indefinitely with correct maintenance and replacement parts.
2 stroke engines do need more work than a 4 stroke and require parts replacing more often, but if done right and you want to keep the motor going there is nothing stopping you.
I guess the big part is supply of the parts and as engines get older manufacturers may stop making what you need. The biggest part however is engine development with engines getting lighter, more power from smaller units, better fuel economy and so on.
I say if you are happy with the engine and can get the parts why not keep it going if you don’t feel the need for a new one.
I had an engine at the start that I was struggling with and ended up selling it on but that was mostly due to confidence issues early doors but now wish I had stuck with it but the metal block I was having made me move it on (fully declaring the issues I had with the motor)
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