Any of you have any experience with Hirth engines ?
Specifically, the Hirth 3503 as a substitute for the Rotax 582-99.
A forum search showed very little in the line of Hirth, but it appears to be a note worthy candidate.
Any input, history or experiences would be great.
Thanks
edit:
hmmm...this is interesting http://www.ultralightnews.com/buz1/rtxhirt.html
Maybe no more needs to be said ?