Gold Cup 1.20 twin center crankshaft

HP engines (Hirtenberger, AG Austria) tech support. Owned by RJL Industries since 1990

Moderator: SteveM

Gold Cup 1.20 twin center crankshaft

Postby Cryhavoc » Sun Aug 23, 2015 3:30 am


For some time now I have been wondering about how the center assembly of the !.20 Power twin is constructed. I can't seem to find pictures anywhere other than an assembled engine pics. From what I can see, the center housing is one piece so how is the crankshaft constructed???

If the center housing is one piece then either the front drive to the center crankshaft, or the crank for the rear engine must be removable to get the center shaft into the housing right? If so, how is that done so it wont come apart during running?

Also, This twin is alternate firing I think I read, doesn't seem possible with such a short center piece? Still trying to wrap my head around how this would be done unless very small ports are drilled which would limit power. Or is the intake angled some how???

A lot of questions I hope some one can answer for me. I tried to buy an engine but I can't seem to find one for under $300. I missed out on one on RCGroups the other day. Someone sold a marine version for $85. Must not have known what he had.... Oh well.

Posts: 7
Joined: Thu Aug 13, 2015 5:37 pm

Re: Gold Cup 1.20 twin center crankshaft

Postby MECOA » Sun Sep 06, 2015 9:58 am

Front power take off plate is press onto the center crankshaft and pinned.

Yes alternate firing and the 2 crankshaft ports are full size and angled in each direction.
Site Admin
Posts: 1095
Joined: Mon Jun 30, 2003 9:48 pm

Return to HP (Austrian) engines Tech Questions

Who is online

Users browsing this forum: No registered users and 1 guest