Hi Casual Oldtimer.
You have yourself a really nice Falcon there. It looks in very good condition indeed.
In terms of identifying it, there are several clues to help us. First the brakes. Shimano 105 SLR were announced late 1986 for the 1987 model year. They are one of the best road bike brakes you can get. SLR stands for Super Linear Response I think and should be very smooth and effortless to operate.
The Biopace chainset were introduced in 1983 and were fitted for about ten years. So we are looking at mid 1980s.
The interesting part is the "Made in England" addition to the down tube "Falcon" transfer with the union flag on top. This had been used for a number of years before the mid 80s but in 1986 Falcon published a USA catalogue with some different models and that is when they started to add the "Made in England" to their machines.
The head tube badge is the classic foil badge that started to be used when Ernie Clements left the company in 1982 and it continued in use until the mid 80s - I have not been able to pin down an exact date when it was superseded.
So in terms of year, I would say it is probably 1986 or possibly 1987.
The use of Reynolds 531 tubing - which is excellent - is interesting because by 1986 the British catalogue shows Falcon using Reynolds 531c, 501 or cr-mo for its best bikes. However, the 1986 USA catalogue shows the Triathlon 105 with 531 tubing and forks. It has Shimano 105 throughout including the biopace chainset.
It appears that as you are in the states, so I would say the Triathlon 105 is what you have.
