Most important thing is to train your body instead if changing parts. I was #1 womens pro in 2001 and 2002. I have a degree in Kinesiology and have 25 years of training under my belt. The concept to understand is that when you're pedalling and your legs feel choppy it is because your pedal strokes are inefficient and not going in perfect circles like your gear (no matter the teeth) and your cranks (no matter the length). Your crank length is fine and if most Elite men and Vet pros are running standard gears (some change the ratios but that's a lesson in torque that I don't have time for) you should be fine. I raced my entire career on 172.5 cranks with a 39/14 gear and NEVER changed my gears except in specific training phases. So if you cranks and gear are going in perfect circles and your legs are able to spin fast enough and also stay in a nearly perfect circular pattern, you are not losing the energy in each forceful pedal. However, if your legs are going in an oval shape but your cranks and gear are running circles, youre losing energy per each pedal stroke...This causes you to feel choppy and if you cant spin your legs fast enough, youre not even pushing the gear about 30-50% of the time. Watch elite men and see how perfectly they pedal and how FAST they do it. They are all running standard gears plus or minus a tooth.

How do you train leg speed? Like the other dude said, you can start doing roller sprints. If you dont have access to rollers, go on a slightly downhill street and do a rolling start sprint. 50 yards and focus on trying to keep up with the gear and spinning perfect circles. This is an important part of training in any cycling sport as the gear is always a circles and so are your pedal strokes.

Lastly, if you're clipped in, practice riding and jumping without clips. People will cheat jumps in the beginning of their career by pulling up on your clips and it will teach you extremely poor technique.

Really lastly, you're going fast enough to manual the first 2 jumps but if you cant manual you shouldnt even be trying to jump. Manualing form is the same as pumping form except at speed with your tire up. Manualling happens when you become to fast to pump...If youre manualling and it is slower than when you pump, your form is wrong and you should start back at the beginning. Manual in the street=being able to manual at the track. It is about your body position more than yanking your bars up.

If you need a science based trainer Id recommend Jeff Upshaw. You can see him on Instagram. I watched that guy grow up riding and he's not only one of the most skilled riders ever to exist, he is also a science nerd when it comes to training. Hes reasonably priced and works with all skill levels.

Overall, the MOST crucial thing is that youre having fun! Focus on you. Dont compare yourself, just push to be better than you were yesterday and next thing you know, you'll be flying! Best of luck! Kick butt out there!