Back wheel hopping in sprints

[Lewis Moon]

I'm having an issue with my back wheel hopping around during sprints. I'm pretty sure I'm pulling it off when I pull up on the pedals, so it's probably a bit of uncoordination on my part. It's kind of hard to spot exactly where I'm screwing up, so, anyone have any suggestions for techniques to practice to prevent this?

[bostondrunk]

I'm having an issue with my back wheel hopping around during sprints. I'm pretty sure I'm pulling it off when I pull up on the pedals, so it's probably a bit of uncoordination on my part. It's kind of hard to spot exactly where I'm screwing up, so, anyone have any suggestions for techniques to practice to prevent this?

I've done the same. Try practicing sprinting one gear easier at a higher cadence and/or smooth out your pedal stroke.

[fignon's barber]

Maybe lunging a bit too far forward coupled with a slightly worn rear tire? Also could not bending your torso low enough when out of saddle sprinting (compensate by leaning more forward).

[rockdude]

Body position and weight distribution. Chest and head low, back flattish with butt sticking backwards. Many times throwing the bike side to side makes the problem worse. Bottom line get more weight on the rear tire.

[shovelhd]

You need to practice using form sprints. Form sprints are exactly what they suggest they are. You are working on sprint form and not even thinking about power until your form is efficient. There are some good form sprint drills in the books you already know about. My favorite drill is a stepped drill. First set, 5x2, small ring, 39/17, slow rolling start, 100 meters. Focus completely on your position, cadence, and efficiency. The next two sets are 5x1, big ring, gear corresponding to your launch cadence. If you don't know what that is, that's a separate question. Use 95rpm for now. 2nd set starts at 23mph, increasing power but maintaining form, shifting up when needed to stay in cadence. 3rd set is the same, with the launch speed at 27mph. Once you get good at form sprints with repeatable power and efficiency you can turn set 2 and 3 into all out sprint practice.

[MattTuck]

Avoid sprints. Attack early and solo to victory. Problem solved.

:hello::hello::p:p:D:D

[Gummee]

IIRC it was Davis Phinney that said your saddle needs to brush the backs of your legs in a sprint.

So that's what I've been doing for decades now.

Keeps the weight back and keeps the rear end of the bike planted.

So... To the OP: your weight's too far forward and you're lifting the wheel off the ground. Shifting your weight back some should prevent that

M

[Ti Designs]

You need to practice using form sprints. Form sprints are exactly what they suggest they are. You are working on sprint form and not even thinking about power until your form is efficient...

Sounds pretty much like my telephone pole to telephone pole sprint workout...

I break the skills of sprinting down into two different types of drills, form and power. The form drills are in a small gear, you roll to the starting telephone pole, then it's up to top cadence as quickly as you can get there, until you get to the second pole. Because it's done in a low gear the power isn't there, nor is the strain on the body, so you can practice this over and over. I have my riders do one telephone pole on, four off (sprinting every fourth one), and slowing down between them (that's kinda important), and they can do that run a half dozen times. That many times means you can adjust what you're doing and see what works well. In cases where problems keep showing up we use a video camera on an e-bike.

The second drill is about power. You roll into a hill in way too large a gear, pick a start line that's on the hill, then it's 6 pedal strokes. The hill keeps the cadence from picking up, so you have all kinds of time to understand how you're putting power into the pedals. This is where it helps to think about opposing the force on the handlebar and pedal - you're trying to rip the bike in half (I've had a rider succeed in doing that). My one warning when you start this is not to go to full throttle at first. It's easy to understand how pulling on the bar draws your body into the pedal, but if you yank your front wheel off the ground you're probably not winning any sprints.

[ergott]

My sprint form comes from riding up hill out of the saddle in sprint position. I can concentrate on form for a longer period of time and let the body get used to the position. It's easier to maintain a steady speed and resistance to the pedals on a grade. Find an medium grade that's a couple tenths of a mile long.

You have to internalize good form before the lizard brain can call upon it in the heat of battle.

[ultraman6970]

Are you sprinting like 200 meters standing up or the problem happens when you are sprinting seated aswell?

[Lewis Moon]

My sprint form comes from riding up hill out of the saddle in sprint position. I can concentrate on form for a longer period of time and let the body get used to the position. It's easier to maintain a steady speed and resistance to the pedals on a grade. Find an medium grade that's a couple tenths of a mile long.

You have to internalize good form before the lizard brain can call upon it in the heat of battle.

learning a new "habit" is always hard. This sounds great!

[Lewis Moon]

Are you sprinting like 200 meters standing up or the problem happens when you are sprinting seated aswell?

I usually don't sit down until I'm starting to spin out. I can increase and hold a much higher cadence in the saddle. No hopping there.

I try to enter a sprint (jump) at around 80 RPM and I get the hops up until around 90 - 97 RPM when I sit down and concentrate on spinning up the rest of the way to ~120 - 130 RPM.

[Lewis Moon]

Sounds pretty much like my telephone pole to telephone pole sprint workout...

I break the skills of sprinting down into two different types of drills, form and power. The form drills are in a small gear, you roll to the starting telephone pole, then it's up to top cadence as quickly as you can get there, until you get to the second pole. Because it's done in a low gear the power isn't there, nor is the strain on the body, so you can practice this over and over. I have my riders do one telephone pole on, four off (sprinting every fourth one), and slowing down between them (that's kinda important), and they can do that run a half dozen times. That many times means you can adjust what you're doing and see what works well. In cases where problems keep showing up we use a video camera on an e-bike.

The second drill is about power. You roll into a hill in way too large a gear, pick a start line that's on the hill, then it's 6 pedal strokes. The hill keeps the cadence from picking up, so you have all kinds of time to understand how you're putting power into the pedals. This is where it helps to think about opposing the force on the handlebar and pedal - you're trying to rip the bike in half (I've had a rider succeed in doing that). My one warning when you start this is not to go to full throttle at first. It's easy to understand how pulling on the bar draws your body into the pedal, but if you yank your front wheel off the ground you're probably not winning any sprints.

Wow, that sounds really great. On my list!

[ultraman6970]

You are doing the right thing IMO... Hmmm just a thought ok? If you have a problem of technique mixed with hulk power a way to fix that is go out in a fix gear with not a lot of gear, you will be forced to pedal correctly while doing cadence and even more while sprinting, that can help to correct some of the postures you may have (maybe too far to the front?) and such.

You cant abuse of the power using a fix gear, you will work in your acceleration aswell. In the road honestly you dont need to be that explosive.



I usually don't sit down until I'm starting to spin out. I can increase and hold a much higher cadence in the saddle. No hopping there.

I try to enter a sprint (jump) at around 80 RPM and I get the hops up until around 90 - 97 RPM when I sit down and concentrate on spinning up the rest of the way to ~120 - 130 RPM.

[carpediemracing]

I don't remember if you have a powermeter or not. One of the things I did when I first got mine was to jump at different rpms and see where I got max power. I found that if I jumped at about 100-110 rpm I had the highest power. It didn't feel that way but that's what the data told me. I'd been jumping at a much lower cadence, as low as 70 rpm (uphill finishes - I was really only thinking of the uphill finish at Bethel).

Using my findings I tried to train myself to jump at a higher cadence and also to wait to shift (while I sprinted) so that I'd "land" in the next gear at a higher cadence. It's like shifting a car so you end up at an optimal acceleration point in the power curve.

I won't say that this process got me a bunch of wins but my field sprinting has been pretty consistent - I think one season I won every field sprint I contested. Unfortunately I think none of them were for the win, maybe one.

Also form sprints. In a different life I was a much better violin player than I ever was a bike rider. One of the things I learned (and I'm sure it's the case with pretty much any skill thing) is that I could perform a move best if I first practiced it in slow motion, being over precise in how to do things, then speeding things up.

With out of saddle stuff I'd roll in a pretty big gear, maybe a 53x15 or so, not very fast (10-15 mph?), very slow cadence, and basically rehearse what I needed to be doing on the bike. Rock the bike, weight back just a touch (back in the days of riding too-short-length bikes), reinforcing the coordination between pulling up on the bars and pushing down on the pedals. I exaggerate stuff - I'd tell others to try and scrape their bars on the ground. The idea is to learn the coordination between the arms and legs.

Finally your head should basically follow a straight line. The rocking happens below your head, not at your head. When I review clips I know I'm done when my head goes from side to side in a sprint.

I don't think you're the person but someone a while back asked me for some sprinting tips. He had some clips where other riders caught him on camera doing jumps or efforts (attacks or final sprints). One thing that popped up immediate was that he was pulling the bars sort of "backwards". He was pulling up on the bar when he was pulling up on the pedals. This was because this is the natural way to stand on a trainer. His first job was to unlearn what he had learned/taught his body to do in a sprint.

[nooneline]

When I think of rear-wheel hopping in sprints, I tend to assume that the problem is spending too long on the downstroke of one's pedalstroke. If you get out of sync with your pushing and the pedal location, then you're awkwardly weighting and unweighting the wheel through the pedals in a way that's out of phase with the pedal stroke. And that can cause hopping.

It goes like this: you push the pedal down, and then the pedal reaches the bottom of the stroke. If, at this point, you keep pushing down, then your body rises UP. You're pulling the pedal up the backstroke when you start, but because your body weight is up, this can also mean unweighting and lifting the rear wheel when your body weight is coming down again.

As a trackie, I tend to use undergeared sprints (even on road bikes) to work on form. Start from 80rpm, accelerate, and don't start shifting until you're above 130rpm - and only shift to stay in that range. No need to kill yourself to keep the top-end going. These tend to be not particularly taxing, even if you're hitting good power numbers. Most people can do a half a dozen in a session without incurring a bunch of fatigue that will affect the next day's workout, so they're easily integrated into a training program without sacrificing other work.