Motorcycle Questions? Ask a Mechanic.
Hi and welcome to the site, I’m Louie. Sorry you had to wait awhile but I’ll do my best to help.
Initially, "...usually when I put in reverse...", but not always?
And please confirm that the original fuse was 15A ?
Likely possibility would be a pinched wire or rubbing raw to frame since it would appear to be intermittent.
Please check which 15A is blowing; normally would have a label on the fuse box/cover then we can determine the wire color to be traced.
Depending on the version, if it were: