I have no recollection of the make of any of the bikes, but I seem to remember Ronnie's was a Schwinn...maybe you could date it. His was new and mine and Charles's were old used bikes. We used to do dare devil stunts on them....we stacked up concrete blocks in the alley and put a 2 X 12 on it to make a ramp. We spent many hours seeing who could jump the furthest. The alley was gravel and we had many scrapes and bruises, bloody elbows and knees. During those long hot summers we would think nothing of getting up early in the morning, filling our canteens with water and heading out for neighboring towns, distances of 15 to 20 miles each way. We took a patch kit from Western Auto and tied a hand pump on the bike for our numerous flat tires (our tires were old also). In those days when we were finished with the bikes (when we got a car) the bikes went to the city dump.
I wrote a story about learning to ride a bike on the gravel roads in Richards, Mo. when I was 6 and Charles was 8. That would have been in 1946. It was a full size bike and Charles could not reach the pedals. I would carry a 5 gallon bucket for him to stand on to get onto the bike. The only way for him to stop it was to crash it into the ditch, which he did quite frequently. I would run along with the bucket...he would ride and I would chase all over town (500 population) with the bucket.