Darth Steele

I think that team Sky should sign you up, you sound like a natural, a real monster.

gregf83 

He wasn't necessarily referring to himself but the well known saying that 'sprinters are born not made', i.e. genetics (specifically the ratio of fast twitch to slow twitch muscle fibers) is the biggest factor in determining a sprinter's success.

EnsitMike

I have trouble breaking into 40 on a pretty nice downhill near my house and I'm running 52-12. That aside, I can pull 34 without even getting out of the saddle on flat ground with a headwind.

Not positive, but all that makes me believe that gearing is the culprit.

Bandera

That is not what I was getting at, riding a moderate Fixed Gear on the road to improve pedaling technique and develop a broader power band is. Riding FG on the road is the traditional training technique to develop both power & supplesse. It's the best way to get the high RPM well coordinated leg speed that is key to acceleration.

Better yet get on a velodrome, get a coach & proceed if you want to improve your sprint.
That all takes place on fixed gears.

-Bandera

therhodeo

Leg speed is the culprit.

carpediemracing 

Sprinting is two parts - the jump, or acceleration, and the actual sustained speed, aka the sprint.

Acceleration is largely based on genetics, at least based on what I've seen. An untrained rider with a good jump always has a good jump. A rider with a good jump will often not realize it for a while, their initial reaction is that no one else jumped. If you jump and then start wondering if you went on the wrong lap or there isn't a town line sprint etc then you probably have a good jump. If you accelerate and you don't blast by a few riders like immediately then you don't have a good jump. I've never seen a rider with a bad jump have a good jump. I have seen riders with good jumps get so out of shape that they blow up 2-3 seconds into the sprint. Until then you're just scrambling to stay near them.

Top speed can be trained to some level. I've seen "non-sprinter" racers (local level Cat 3) defeat a good sprinter (former Olympian on the track, multi time Masters National Champ in crit and track) in a big race (Nutley) by going from far enough away that the sprinter simply couldn't get around. I've followed riders who have poor jumps but a long sustained top speed - after 200-300 meters I just couldn't hold their wheel, even though I was drafting them.

You can work on sustained and top speed. Working on the jump… not so much. You can hone it, sure, based on whatever level jump you have, but you can't radically alter your jump. For example you couldn't change a Froome into a Boonen or Kittel etc etc.

I had a teammate ask me why I didn't lose weight and contest road races. I asked him back why he didn't lift weights (he used to be a body builder but his max power is well under 1200w, about what I hit when winning a Cat 3 race) and contest sprints. He replied that no matter what he did he couldn't get his peak power above a certain number. I told him that in the same way I can't get my threshold up over a certain (very low) amount. Therefore it wouldn't make sense for me to work super hard so I can get dropped a minute later on the first climb, just like it wouldn't make sense for him to focus on increasing his max power by 50 or 100 watts and getting 15th instead of 20th.

merlinextraligh

All out sprinting speed is pretty much irrelevant. Finishing ahead of the people you're sprinting against is what matters.

Best way to get better at that is practice. Go out with friends, club members, or teammates and do sprint intervals. Sprint to designated points, and then ride relatively easy for recovery between them.

The leadout, and the competition will make you faster.

Play with different tactics, jumping early, jumping late, following different wheels, trying to jump from the front, etc, and you'll learn what tactics work best for you.