I have been helping my friend out with his old Harley It ran pretty good on the old batteries but would hold the charge. It had regular automotive 6 volt batteries in it. We replaced them with cart batteries, after putting the right batteries in the cart goes about 5 mph slower than before. Checked voltage and all looks good around 19.5 volts on each 3 battery bank and just above 18 on each bank when going. Can distinguish all four speeds while driving. Could it be the brushes going bad? Any easy way to identify which motor is in it? I know on the Harley I used to have there were small access holes the I think were for checking brushes. His doesn't have these.
--John
--John