Can my friend cycle 70 miles in 4 hours?

On an old mountain bike? I find it very unlikely. He will be battling the fact that he isn't used to that much seat time, plus the old mountain bike.

On a cheap road bike, it certainly seems reasonable.

Well, you know the answer to this.

Is he the type that will bail if he’s way off pace? I say he can hold 17.5mph on an old mountain bike, assuming weather isn’t horrible, for 10-15 minutes. It will be a rude awakening from there.

VAboi wrote:

Well, you know the answer to this.

Is he the type that will bail if he’s way off pace? I say he can hold 17.5mph on an old mountain bike, assuming weather isn’t horrible, for 10-15 minutes. It will be a rude awakening from there.

On a road bike maybe. Though not a lot of people can hold 17.5mph for even an hour.

Not a chance. Mountain bikes, whether new or old, just don't roll as well as a road bike. They are definitely not as efficient and are much heavier in weight. His training isn't enough either to have the endurance built up to even do this on a road bike.

Possible if there is time to put slick tires on at full inflation and remove all unneeded gear like brakes and brake cables, maybe get it on a 1x, have him wear compression gear and tuck aero on very narrow bars. Might need some muscle relaxants and a camel back full of salty espresso.

Ralph Diseviscourt set the 24 hour road record at 568.8 miles (915.39 km) in Vianden, Luxembourg on 11 July 2020.[50]

That's nearly 24 mph for 24 hours.

Pretty sure he can hold 17.5 mph for 4 hours.

on a road bike, yes.

The Unkle wrote:

Ralph Diseviscourt set the 24 hour road record at 568.8 miles (915.39 km) in Vianden, Luxembourg on 11 July 2020.[50]

That's nearly 24 mph for 24 hours.

Pretty sure he can hold 17.5 mph for 4 hours.

But did he do that on an old mountain bike?

It would be very doable by this guy on a road bike. But even on a road bike there's a good chance he wouldn't make on his first try without getting accustomed to riding that length of time. His butt might not take it and logistics comes into play. Specifically, he wouldn't know how much water he'll need, how to carry or where to get it, and some people would need some calories in that length of time.

Do you ever get anything right about anything?

No chance whatsoever this guy rides a MTB 17.5 mph for 4h. Or 1h.

No. He can’t do it.

Primary reason: The bike. The old mountain bike will make it really really difficult. Any road bike would make it completely doable.

Other reason: Not enough time in the saddle. If you told me that he had been doing some 50-70 mile rides, then I would think that he could do this successfully even if his other long rides were slower. He’s going to feel way different during the fourth hour than he does during a one hour ride though.

Solomonn wrote:

Do you ever get anything right about anything?

No chance whatsoever this guy rides a MTB 17.5 mph for 4h. Or 1h.

Hell, I am old and no bicyclist but when coming back from knee surgery I went from covering 12 miles in an hour on a mountain bike to 21 miles less than 4 weeks later.

what's your point? i can make outrageous speculations based on the performance of world record holders too.

have you ever tried to maintain 17.5 mph on a bike for even an hour? it's harder than you think. also the saddle soreness is going to destroy this dude if he's only used to an hour at a time. it's no joke.

Solomonn wrote:

Do you ever get anything right about anything?

No chance whatsoever this guy rides a MTB 17.5 mph for 4h. Or 1h.

No he doesn't.

The Unkle wrote:

Solomonn wrote:

Do you ever get anything right about anything?

No chance whatsoever this guy rides a MTB 17.5 mph for 4h. Or 1h.

Hell, I am old and no bicyclist but when coming back from knee surgery I went from covering 12 miles in an hour on a mountain bike to 21 miles less than 4 weeks later.

21 miles, sure but in what time frame? 2, 3 hours?

Rocky Mountain High wrote:

The Unkle wrote:

Hell, I am old and no bicyclist but when coming back from knee surgery I went from covering 12 miles in an hour on a mountain bike to 21 miles less than 4 weeks later.

21 miles, sure but in what time frame? 2, 3 hours?

" I went from covering 12 miles in an hour on a mountain bike to 21 miles less than 4 weeks later."

Gee. What could that possibly mean?

if you actually covered 21 miles in one hour on a mountain bike after 4 weeks of biking, you may have picked the wrong sport dawg.

The Unkle wrote:

Solomonn wrote:

Do you ever get anything right about anything?

No chance whatsoever this guy rides a MTB 17.5 mph for 4h. Or 1h.

Hell, I am old and no bicyclist but when coming back from knee surgery I went from covering 12 miles in an hour on a mountain bike to 21 miles less than 4 weeks later.

This did not occur

The greatest distance cycled in 24 hours on a mountain bike is 577.78 km (359.02 miles) and was achieved by Adrian Ellul (Australia) in McLennon Park, Walkerston, Queensland, Australia, from 9 to 10 October 2015.

@ 15 miles an hour for 24 hours.

Yet someone cannot average 17.5 mph for 4 hours on the easiest course possible?

Come on.