it really depends on where you are biking, because my dad and i have made a 50 mile trip in about 4 hours, not including stops, but it was completely flat the whole way on a highway sort of thing. If it is the same sort of circumstances and your going with tailwind, i would say about 6 hours, but it really depends on the hills involved, because one large hill could slow your time very much and take out a lot of energy, and also check the weather reports to see which way the wind will be blowing because riding with or against the wind is a huge determining time factor.
good luck and hope this helped
p.s. make sure you have a good road bike with a great seat because sitting on a crappy seat can get really painful after a few hours
this is obvious but – build up go a mile 2 4 8 16 32 etc 3 months is enough time if you do this about 3 times a week be sure you can go about 40-50 miles you don;t have to really ride 70 a million times 40-50 is enough do that 4-5 times first if you survive that with some pain you won;t have too much more at 70 or work all the way to 70 it can;t hurt now 100 is a different matter suddenly it starts mattering how much you eat, how fast you go, strategy matters for 70, you just do it there isn;t a strategy other than ‘work up to it’ wle.
It took me like 5 hours to bike 60 miles from San Jose to San Francisco (California) on a road bike; i was an average teenager/adult at the time and a bit overweight. probably would take me 4-5 hours NOW for 70 miles.
In the end i was tired and my rear wheel was WAY out of true because two spokes broke. I had to replace the wheel because of rim damage. Also my butt felt like a rock at the end – but the padded shorts helped.
If i were to do it again, i’d probably need to use more durable wheels; and also fix my seat for comfort A LOT MORE!
At 70 years old, I can Avg 16.88 mph. 87 cadence avg, 102 hr. Sunny and 88* for 70 miles. while Riding 60 miles the day before. Cycling has kept me both Alive and Positive while overcoming my Diagnosis of having
MM-Bone Marrow Cancer. My wife of 48 years now follows me for my support. Can’t Beat that.
She thinks I’m a PRO…LOL….
ENJOY YOUR CYCLING and STAY IN THE MOMENT…
depending on the bike it could probably range from 3 and a 1/2 to 5 hours on a road bike depending on the speed your going and one a mountain bike it would take a little longer and probably even longer on a single speed bmx
I have a route that’s about 74 miles that I ride pretty regularly. It has a few big hills and takes about 4 hours 15 min.
At what speed:
At 20 mph… 3 1/2 hrs
At 15 mph… 4 2/3 hrs
and if you can maintain an average of 10 mph….7 hrs.
On my usual roads and usual weather (no too windy), about 3.5 hours unless I’m close to a race. Then it’s more like 3 hours.