4-3-1 is the ratio these days, ie 4 schatz -3 bobl + bund (for going long)
For charting the ratio is the same, price should be around 206.50s now. 1 fly tick is 10 euros with one set(4 3 1) on.
I use bollinger bands with all my spreads, especially Fly as it does have a mean reverting tendency. Start off with half your clips and allow one average in.
except on days before trichet talks leading upto his ECB speech. Those days follow the trend blindly.