I really don't know anything about the hirth engine ,,never seen one fly
long enough to establish any kind of history . The nickle sil cylinders
works well for a four cycle engine but it has failed badly in the two cycle
except model airplane engines . No matter which engine you choose , one will
always have problems of some sort . Rotax seems to be the engine that gives
the least amount of it.
"J.P." wrote in message
ups.com...

wrote:
chuck wrote:
I know that just about everybody has bad-mouthed the 2si, but what are
your
opinions of the Hirth series?

I do not know about all of them but I have had great experience with
a 3203 (fan cooled). The basic concept of nikocil/aluminum jugs is very
sound for air cooled engines. It is how Porsche 911s were made back
when they were aircooled.
As for the 2si, I would take another look at the new ones with the
larger flywheel - ignition trigger spacing. That should have cured
their ignition issues.

Hello, I tought 2si did no longer made engine for aviation

J.P.