I bought the Zumo 550 because from the advertising, it seemed to offer everything I wanted - bike power; connection to autocom and full European maps. It was expensive, but, as it turned out, so well thought out.

	Click thumbnail for VGA image.
The unit is waterproof, and has no external connections, other than those underneath - a 24 contact strip, and under a cover a SD memory slot and a USB connector. The trick comes in the cradle - there are two of them - one for the bike, one for the car.
Here is the bike cradle. The Ram mount is one that I have attached to the rear of the unit - its actually a mounting that is intended to fit over the clutch / brake lever clamp.
The cradle has a couple of sockets - one for the mike, one for the earpieces. Autocom manufacture a cable and adapter which plugs into these at one end, and directly into the autocom at the other end. It comes with a special cable to connect the cradle to the bike's battery. The unit recognises when it has external power and will charge from the bike's battery when connected.
The Zumo 550 connects to the mobile phone via blue tooth - so no extra wires there. It makes a connection as soon as it is turned on, and will (if permitted) download the address book, and the lists of last calls - dialled, missed and answered ! The phone can be controlled entirely from the Zumo screen, and will even transfer voice dialling if the phone supports it. Mine is a Sony Ericsson K510i. It wouldn't connect by cable to the autocom, but quite happily connects via bluetooth throught the Zumo
The cradle for use in the car has built in speakers. This allows it to be used as a normal car Sat-Nav, attached to the windscreen, or if you dont want to leave the tell tale suction cup circle on your windscreen, the box contains a circular disk with an adhesive pad to allow the mounting to be placed anywhere in the car. Power is from a special cable which plugs into the cradle at one end, and itno the cigarette lighter at the other.

I thought long and hard about this, and tried all sorts of alternatives before commiting drill to plastic. The kit came with two ram mounts - one for clamping to the brake / clutch lever mountin, the other - with a circular base - for attaching to the rear of the Garmin cradle.

I played with many positions and ended up using the circle mount to bolt to the top of the dash, and used the clutch clamp mount to fix to the rear of the zumo.

		Click for VGA image
I played with many positions and ended up using the circle mount to bolt to the top of the dash, and used the clutch clamp mount to fix to the rear of the zumo.
I cut a circle of old sheet rubber I had lying around, and a circle of sheet aluminium. Carefully drilled 3 holes to match the holes in the RAM mount, the unit is clamped onto the plastic in such a way that the load is spread as widely as possible. Awkward getting the washers and the nuts on - there's barely finger room. But I discovered the benefit of a magnet attached to the bolt head- it keeps the washer in place while you fumble with getting the nut in position. I didnt have nyloc - so I used spring washers, with a locknut on the easiest to access bolt end.
This picture shows the cradle attached with the RAM clamp. I've left the Zumo out of the cradle to show the mounting. This is a very sturdy mount - almost as good as being mounted to the frame.
The 3 cables which feed to the power supply, the mike and earphone inputs to the autocom adapter. The cables are spiral bound and covered in tape. I feed the end through the side of the grey cover. I use a section of mountain bike inner tube to slide over the exposed ends, and this slots between the RAM mount and the windscreen when not in use. It is tidy, keeps water off the exposed connectors, and prevents the loose ends from rattling around.