Hi guys,

I need some advice regarding engines. I am fairly new to pattern flying and have recently acquired a pattern plane. The trouble I have is that I am not sure what engine to buy. The requirements of this plane states 60 to 90 2-stroke.

Firstly I do not seem that there are any engines larger than 60 with a rear exhaust. Is there any?

I have also looked at 4-stroke engines, specifically the OS Surpass 90 with pump and the YS110. At this point I am all confused as there seem to be many disadvantages with 4-stroke engines i.e. weight and vibration to name a few. Some person also told me that the YS engine will only run properly with a 25+ percentage nitro, is this true? If this is true why does it not apply to the OS 4-strokes?

What is the main pro’s and con’s of 2-stroke vs. 4-stroke?

I guess that is enough for now, I would really appreciate it if some one could enlighten me regarding all these issues.

Thanks