I had a cigar lighter socket fitted (badly, as it transpired)* to my 50 cc "Daytona Sprinter". However, it's quite impossible to see the screen of my "TomTom Start 25" in normal sunlight. In addition, the sucker doesn't stick reliably to the handlebar plastic cowling. So I need to have a think.
*Wires wrapped around the battery terminals and no fuse.
The bike manages to pull my slightly dumpy body around at up to 60 km/h on the flat and 20 km/h uphill in 2nd gear. I've only once found a hill that required 1st gear. I'm going to upgrade to 125cc when funds permit. (I don't trust myself on anything more powerful.)