I have a Seneca 9" lathe with cast iron bearings. The countershaft
assembly has two pulleys, but the motor only has one.

The rpms are as follows:

direct: 558, 350, 222
back gear: 80, 52, 32

The max speed seems kind of low, but I'm not familiar with how
fast these lathes were designed to go. From reading the lathes.co.uk
pages, it seems similarly configured South Bend 9" lathes with cast
iron bearings went up to 1200 rpm.

I had the lathe running for 20 minutes at the top speed yesterday
and the bearing caps weren't warm at all.

So would it be OK to put a bigger pulley on the motor? And if so,
what should the top RPM be?

Thanks for any insight,
Aaron