Tell your computer its attached to a 36" wheel

"Ride lots."
E. Merckx

I have preceded the OP in a lot of ways. 59 y.o. starting riding a hybrid in middle TN where there are lots of hills a year ago. I got a drop bar bike not necessarily to go faster but to be able to make it up the hills (thank goodness for triples!). I was averaging around 14 mph or so. We have spent the winter in SW FL where it is dead flat but the wind is always blowing (always a head wind regardless of your bike's direction). I was averaging around 16 MPH in FL until a few weeks ago when I had the opportunity to tag along with a few groups. I also started riding almost exclusively in the big ring and am now averaging just over 17 riding around 100 mi/wk. Have also gone from 210 to 195 over past few months. Getting to 19 mph solo is really cranking from my POV. Just keep pushing your limits, work some intervals in 1-2 times per week. Speed comes on its own when you least expect it.

Honestly, I'm happy going 15. The impetus for my question is entirely thinking about what it is going to take to get that century under my belt. Maybe I shouldn't even consider it for a few more years. My distance appreciated nicely over the course of the first 6 months of serious riding, but the speed did not. I didn't know if it would come with time or you had to train to achieve it.

I remember last June I was just starting to really get into riding. I had worked my way up to 20 milers and felt good about it. I went over to the Harpeth River Ride here in Nashville just to check it out and maybe get a glance at Lance and was watching the folks come in from the ride. I was amazed when a 'grandma', maybe 65, came over the finish line after riding the 62 miler. Unbelieveable! This year I'm going to ride that 62, so it's neat how your perspective changes.

Boy, ain't that the truth! I don't havfe an athletic bone in my body

Is it?

Sometimes I get the feeling that if I pushed it just a bit harder for a bit longer that my speed might hop up. In my neighborhood we have endless rollers. It seems like if I get more aggressive charging down the hills, instead of coasting, I carry more momentum up the next hill, I go faster and it gets easier.

So, is there such a thing as "threshold" speed? My "dreaded average fake speed" has gone from 11.5 MPH to around 14 MPH over just a few months, but that might have more to do with finding my recumbent legs than any true major improvement.

I swapped them out for some 32s Ha! I've wondered if I should have gone to 28s, but for now I'm keeping what I've got.

In actuality, I'm thinking about selling the Crux. My impetus for buying it was to go faster. That didn't happen. After about 400 miles on it, I'm still less comfortable on it than the hybrid. If I don't go faster plus I'm less comfortable, why should I keep the money tied up in it? Y'all convince me cause right now I'm thinking of getting out of it and putting the money in the bank and just riding the Mendota for a few years. The Crux is sweet and I thought it might actually end up replacing the Mendota, but obviously comfort means a lot. Maybe I should give it some more miles before I decide. I mean, 80% of the folks out there right drop bar bikes, so it must be me, right?

If your hybrid is more comfortable than your road bike, your road bike is not setup correctly, and you have a poor fit for your bicycling style.

Only viable plan in the entire post.

I am 68 years old and last year rode 8,450 miles. On an average ride I may climb 2,000 feet, I have stop lights, joggers, car traffic and
who knows what to tend with. If I ride in town that is exacerbated by any number of things and my normal cruising speed is between 15
and 20 mph but at the end of my ride it usually is 12 to 14 mph average. I can't imagine the cruising speed I would have to maintain
to hit 19 mph average.
If you can hit your bogey and still enjoy riding more power to you.

May be. I'm 6'2" and bought the 61cm bike. It's the largest one they make. My Mendota is a 22.5, also the largest.

I set the seat height to lowest pedal distance to be the same between the two bikes. It was originally higher and it feels better in its current position. The fore/aft of the saddle is set so the plumb line from below my kneecap goes through the pedal spindle. All of the spacers are underneath the steering stem which is the way it came from the factory. On the Mendota, i had to get a stem riser to give me another inch and a half of rise there to get it really comfortable for me. Now it's golden. Any pointers on what else I might look at to adjust would be appreciated.

I'm almost 55 and have been riding seriously for 5 years, approx 6-7k per year. Used to average 14-15 for 30-40 miles. Now I can average 17-19 for 60-80 miles. It's a process......ride as much as you can and enjoy.

I just went back and looked at my speed from a year ago. It is up about 1 to 1.5 mph. But a year ago, I was just getting started. If I could increase 1 to 1.5 every year for a few, I'd be happy!

Skinnier tires would give you less rolling resistance. May not get you where you want to be, but you might see improvement with them.

If you're bent on getting rid of the bike, I won't try to stop you. Know that a more aero riding position may take a while to get used to. I got a bike with drop bars just about 18 months ago. It was my first bike of that style in about 34 years. At first I couldn't ride in the drops for 30 seconds, no joke. It was tiring and just plain hurt. Now I can ride in the drops for 30 minutes if that's what's needed. The aero position has many benefits, but getting to the point where it's comfortable can be a process.

Get a protessional fitting by domeone who takes the time to understand your riding desires. There are a number of excellent fitting protocols and options.

It's hard to make a high average if there's hills or stop signs on the route.

For example, this is probably one of the fastest rides I did last year (ridewithgps link). We were supposed to have two speed groups, but decided at the last minute to all ride together, and do a mostly flat route. So, to end up with an 18.0 average, a lot of the ride was above 20 mph (click the Speed check box at the red elevation graph at the bottom). I was staying in the draft of the group for most of the way, which helped a lot.

To increase your average speed

Stay in the draft of a fast group.
Avoid stops or hills.
Don't count the warmup miles in your average.

Get more aero. I can ride in the drops easily now that I changed to shallow drop bars. It's a noticeable change.

And/or,
increase your power. See this bike speed calculator for a rough estimate.

For example, take the default settings, but keep Set A at 100 watts and change Set B to 210 watts. The calculated speed is 15.0 mph for 100 watts, and 20.0 mph for 210 watts. You have to more than double your power!
Or compare 150 watts on the hoods=17.6 mph and 150 watts in the drops=19.0 mph. That sounds about right.

Put TWO magnets on your wheel.

Seriously, I started riding a tri bike last summer, then had a knee replaced. So this year I'm swimming a bunch, trying to learn to race walk, and trying to improve my speed.

On a tip, for two months I'm riding in nothing but the big chain ring. Now, I did drop to the 34 on one hill last weekend. But that's been it for the last three weeks. Whenever the cadence gets up to 70, I catch another gear. When it gets down in the 50's I try to find a higher gear, or get up out of the saddle.

I'll get back to you in another month, when my quads quit hurting.

And if it's red, there's your 20avg right there.

If finishing a century in x amount of time is important, fine; train for speed in that case. But if just finishing a century is your goal, forget about speed. Tweak your bike for comfort, learn to hydrate and eat on a ride, ramp your miles up, and a century will come.

Just ride faster over short distances and do it many times per ride. Intervals, and increase over time the length of the interval on occasion.

That is not the problem. I am just saying if someone is averaging 15, for whatever reason, expecting a 4 MPH jump in a year or two may take some creative logging. I run my average from door to door. I ride to the start of the ride after stretching and spin till my HR gets to about 122. I don't reset the computer when I get to the meeting place for the group rides and I don't reset it during the cooldown spin heading for home. In a TT or a road race I can hold between 22 to 25 for most of the race. But the recovery ride the next day gets averaged in as well. After all I am on the bike and I am riding so why not add it? A ride to the store may be only 12 MPH but it is a ride and it goes in the pot. 22 miles on the MTB gets tossed in as well. If I am riding it gets logged and averaged. My best 100 miles was at 16.8 and my worst was at 13.6. But like I said that includes stop lights, stop signs and nature breaks.

The enjoyment for my rides increases exponentially with an increase in speed.

You can ride a century without pushing your avg speed above 15 mph. You just need to add incremental miles over time and ensure hydration and calorie intake during the century. You can also rest as often as you need.

I agree with the posters about getting a correct fit. You will get more comfort and power on a bicycle that is set up correctly for your anatomy.

Get a heart rate monitor if you haven't already, and push your heart rate up in intervals. In TN (although I am not exactly sure where Gladeville is) you won't have trouble finding hills. Training on the hills will help improve your speed.

Others have mentioned that going from 15 mph to 19 mph is a monster jump. The major reason that it is a monster jump is power requirements are exponential and not linear. The increase power requirements really get pronounced above 13 mph. Riding into the wind will also help build your strength.

If you don't monitor your cadence, I would suggest doing so and ensuring that you can push your cadence to 90 rpm and above.

Ride with a wife who is starting the spring ramp up for the triathlon season

Wanting to increase my speed also. I live in a flat area. So I am at 260 lbs and have several bikes. One is a touring bike and loaded with gear it's about 65 lbs. I use that for long rides over 50 miles. Past Saturday 83 miles

I put the road bike on the trainer and watch the video https://vimeo.com/23170333 on the warm up middle ring and when i get to the hill i big ring . Just started this and did the 33 minute route three times today. ( Or other training video)

I have been tweaking bike fit for more than a year and have been at this for two years and my average is about 10 mph. But i have done a 100 mile ride and consider 60 miles a training ride.

Rule of thumb when making changes to bike or gear make one change at a time. Test that change

Even though my overall ride average is 10 mph during my rides i will do a sprint or several sprints just to get an idea of how much energy it will take to maintain that. My sprints usually happen while being chased by dogs.

I am taking the approach that in order to go faster later go slow now and work on intervals.