Hello!

Im Matevz and i come from Slovenia.
Recently I bought Aprilia RX50 (1990) with Minarelli RV3 engine. Engine is in very good condition, but it has only 3 gears.
I was wondering if I could buy RV4, RV5 or RV6 complete gearbox and replace it with mine, which has 3 gears. Is that possible?

Thank you for your answers and help!

Matevz

Hello and welcome to this forum.

I can't give you a direct answer to your question but i may be able to help you.

Could you measure the width of the points where the engine is connected to the frame?
Maybe the width is the same of the RV4/5/6 engines.

If you thought that dimension on the picture..
But it is not necessary if dimensions are the same, that gearbox will fit my casings

Have anyone changed RV3 gearbox with another one on this forum?

For as far as i know nobody here has done that before. The RV3 engine is rarely seen here.
I think it won't work, just like the AM6 gearbox doesn't fit into the AM3,4,5 engines.

I wil measure the same width next week, you can also look for the data of the RV4/5/6 engine, maybe it is the same and you can just replace the whole engine.