Hello all,

I recently stumbled across a set of three Riva cylinder heads that appear to be for a two stroke Yamaha jet ski engine. While doing some research I found similar looking heads, but no exact matches. Do you guys have any information about these heads? I attached pictures of one of them. They appear to be two piece heads that are interference fit together.

Thanks in advance!

Click image for larger version. 

Name:	IMG_20191108_154120960.jpg 
Views:	43 
Size:	148.1 KB 
ID:	455878Click image for larger version. 

Name:	IMG_20191108_154111240.jpg 
Views:	37 
Size:	150.4 KB 
ID:	455880 .