pat dasein

I ride 48x15/14 clipeless and when I sprint out of the saddle, my rear wheel pops up, sometimes with every pedal rotation. I could sprint in the saddle but I won't accelerate nearly as fast. This isn't a huge problem but I fell like if I knew what I was doing I could go faster and be more efficient.

pitboss

you should learn to do standing and sitting jumps (sprints out of and in the saddle).

the rear wheel is popping up because you are pulling hard on the upstroke, but have not yet made your opposite pedal stroke efficient.

In short - you need to worry more about form versus speed at this juncture. Picture your EACH of feet making its own perfect fluid circle as it moves through the full pedal stroke. Every stroke. Everytime you pedal.

in time, it will happen without thinking about.
that is pedaling efficiency

pat dasein

That makes since, thanks.

dustinlikewhat

might want to look into some ankle weights, and start wearing them on your weaker leg when you're just cruising around your house. your weaker leg will be the one that on the down stroke your wheel begins to hop on.

(sorry if this is written oddly, I'm sick and on cold meds right now...)

fix

I agree that it's a pedal stroke issue. Try to borrow someone's rollers. They've done more for my pedal stroke than anything else, because you can see the little band jump around.

Ceya

Practice one leg riding. I used to do it when I was racing. Also when you sprint try pulling on the bars . Every action and a postive/negative reaction.

watch video of keirin racing, Olympic riders etc.

S/F,
CEYA!

12XU

I will echo this; Ken at the Major Taylor velodrome had us do many exercises to work on form and balance, one of which was one legged riding around the apron. Also, to make your sprints more efficient, keep your arms rigid and throw that weight to your feet rather than dissipating it by swaying.

pat dasein

bikeforums runs ****.


i was so about to buy rollers too.

12XU

See also: The rollers thread. Get em for the 101 days you aren't outside busting your ass.

mikearena

Also, make sure your weight isn't too far forward. Ideally, your back should be horizontal, and the nose of your saddle should be brushing the backs of your thighs. Or so I've heard.

Retem

this will sound weird and I will get flak for it but take a spin biking class learn to properly spin and you will be alot faster and mor efficient on the bike

learn to do 120 in the sadddle concistantly eheh ha

xsdg

Sure, keeping rigid arms may make a sprint more efficient, but it will also reduce the energy output because you aren't using your arms to help propel you. The bike rocks side-to-side during sprints to move the pedals relative to where the feet would be if they weren't moving. When properly timed, rocking the bike will move the downward-moving pedal up against the foot and the upward-moving pedal down against the opposite foot. Simply put, that means you are adding some force from your arms to the force already being produced by your legs.

If this is a problem, the long-term solution isn't to eliminate the rocking, but rather to get the timing right so that it adds to the pedal stroke. Watch the bikes of any group of professional pack sprinters accelerating at full throttle; they're certainly not staying upright, and their arms aren't rigid either.

piwonka

this is how i think about it too.
i was really drunk one time and was cruising home...i hit a long hill and stood up to climb and my timing was all off with my arms...it was crazy how little power i was actually putting to my rear wheel

mander

My instructor at the velodrome told me the stiff armed, no swaying style of sprinting is for track riding, in order to avoid a pedal strike in the banks.

Ceya

Not only that but you can

1 crash
2 waste alot of energy
3 see 1 and 2

S/F,
CEYA!

trackstar10

well...its mainly just a lot more stable, which is very important in track racing. the only way you will strike a pedal on a track bike is if you go down onto the apron in a corner, or are on the banking very very low, and your pedal hits the apron while sprinting road style. stiff armed non swaying style helps you keep your line better, but the swaying road style is just more comfortable and natural, and easier to do on a road bike because of the geometry.

if you have an actual track bike with track geometry, try both styles. if you just have a "street" fixie or a conversion, try the road style, or whatever comes more natural to you.

mander

The Burnaby BC velodrome (a tight, steep little 200m indoor run) is all beat up in the banks, apparently from pedal strikes. I could definitely be wrong though, I'll take another look next time I'm there. Maybe that tip I got was highly local?