Towing a coil....
As I saw a lot of interest over the web on towing coils I decided to show you how I tow my coils. The first photo shows the sled attached to the bike. I fabricated the whole lot from PVC water pipe and a perspex mat (used in offices for roling seats over on carpet).
The photo below is of the whole sled attached to the ATC (a Honda ATC-110 3 Wheeler Bike). the next photo is the same but with measurements explained after the photo.
Lastly the coil is secured in the normal fashion using a nylon bolt. You may have to flatten the shafts a little to accomodate the coil depending on what size diameter PVC is used.
BACK OF BIKE
As you can see I have mounted 2 x 10Ahr 6V standard batteries to my GPM connector box for the 12V output. This allows me to detect without charging for days. The cable goes down through the tow-hitch to prevent it from tangling on sticks and the like that I may run over and get flicked up. I also wrap it around the towing-shaft for the same reason. You could velco it to the shaft for quick release if you like. I then wrap the headphone cable around the frame so I don't pull it out of the socket.
There you have it. I put my "walking" detector on the back with the coil facing backwards from the rack out along and high above the tow-shaft so it can't get hooked in tree branches etc when I am navigating through the bush! A few things to mention are:
The detector is mounted on the Sled to eliminate any noise from the bike and also to not introduce any losses in extended coil cables. It is better (in my opinion) to have (and easier to make) a good quallity power lead made long than making longer coil cables with joins, all of which could introduce signal strength losses and noise. Another reason is that the 2000 is very susceptible to ignition & electrical noise and this "Almost" eliminates it completely without doing anything to the bike's electronics.
Also with the GPM I have detected nuggets (5gm and above) with a Coiltek 18" DD and Minelab 18" Mono at speeds between 5-15Kmh so you can go reasonably fast when looking for a virgin patch. It will detect smaller but that is what I decided the best receive signal rather than jumping off the bike on every small signal (MANY MANY over rough ground).
Any questions feel free to ask in the forum section.