I have a 1997 Honda Magna ( chain driven ) and it is a PITA to lube it every other tank of gas. I have heard of add-on automatic oilers. Anyone ever had any experience with these? Any idea of the cost or efficiency?

Cliff

There are some good reviews on another motorcycle website, try a Google search for the Scottoiler.
While I myself have never used one of these devices they seem somewhat complicated and IMO probably unnecessary. Oil is important but so is keeping it clean and these things don't clean your chain at all.

You are most likely running an O-Ring or X-Ring type chain on your Magna. If this is the case, you really don't need to oil your chain. Use a dry spray wax to help prevent rust and dirt accumulation.

For myself, I choose to clean with kerosene, lube with heavy duty gear oil and I apply a light smear of moly paste to the inside face of the rollers. I 've done that every 800 km and the chain and sprockets look like new at 13,000km. Probably still overkill, though.

I have been using fluid film on the Viffer for over a year now. How about only once every 2 000 kms

this stuff really is that good, see if you can get locally.

Thrown away the Scottoiler, which came with my bike. I don't like the idea of increased pullution, caused by that <thin> oil flowing continuously and being thrown away by centrifugal force.
I just regularly spray the chain with my favorite chain spray (Motul factory line) and clean it with kerosene when it seems very dirty.

Even this thick "wax" manages to fling-off somewhat, when I ride fast. So what a mess will create a regular oil?