That's where I had mine until one day on a VERY hot day in Northern California the whole plot stopped charging......... Sitting out there in 100+ degrees trying to cool down and then get at the regulator only to discover a wire unplugged from the regulator convinced me in this case to take function over form and it is now mounted where it is all accessible!
I am particularly interested to know where Robert has mounted his regulator. The Vincent twin doesn't have much spare space to fit accessories. (No space to spit through looks good.) Why am I
particularly interested in a different location for my regulator? A salutary tale follows if you have time to read on.
I have the charging system using a 300+ Watt alternator and separate regulator that I bought from Timetraveller around 2009. It has been an excellent system supplying an abundance of power for over 40,00 miles. My regulator is mounted under the battery tray. It has three wires to spade connections.
I have just refitted the front and back ends of the bike back on to the engine unit after reassembling the engine. I told my wife I was going to go to the petrol station just a mile away for fuel. If it felt OK I would take it for a longer ride to a local bike meet to start bedding in the new pistons. It felt good going to the pumps, no pops, bangs or funny noises.
Putting the bike on the stand at the pumps I noticed smoke issuing from the battery area. (Thinks to self: "This is not a good place to have a fire!") I quickly pushed the bike away from the pumps and began ripping wires away from the battery. No fire ensued and so erring on the side of caution I decided to push the Rapide back home, only a mile. Almost immediately somebody on a Harley who was on the way to the same bike meet stopped to ask if I was OK. I said I was OK and would get out another bike when I got home and go to the meet.. A little further down the road another guy on a Honda stopped to ask if I was OK. (Only a mile but I was getting less OK. ) He insisted on helping me push the bike home! You meet some great people on a motorcycle.
Moving swiftly on to the why did this happen .......... Back home after the bike meet, I started to check the wiring. No obvious short but what I did find was that there was no continuity in the earth wire to the regulator, still attached at both ends so an internal break. Checking in the fitting instructions there was a note to say that without the earth there is no regulation. I started the engine and sure enough there was 15+ Volts output from the alternator and 15+ Volts unregulated input to the field coils in the alternator rotor. The regulator was fried and so was the battery. Maybe it would be a good idea to make it easier to check the condition of the three wires to the regulator.
On a positive note, I already have a spare regulator bought several years ago. I have a battery on order arriving tomorrow and I took the bike out for a 15 mile run and it still feels good. On second thoughts, it is a Vincent and it actually feels great.
Now where should I mount that regulator?