Leave to 20 in there.
What did you do years ago for the repair?
If you have a good 'repair', and the solenoid power is going directly from the battery, through the fuse, to a relay, to the starter; then you may need to pull the starter and clean the solenoid. I think that they sometimes get clutch dust in them gumming them up.
Looks like I may be in need of some dusting myself.
I installed the SI kit a year ago when I was experiencing the no start situation on a 2007 Griso.
Everything was going fine.
Lately I have been blowing the 15 amp fuse about every month or so.
The last time I tried using a 20 amp fuse after reading about it here.
Well the 20 amp fuse ilasted about a month or so before blowing.
Other than the dusting mentioned here is there anything else that could be causing the problem?
Thanks