what is the optimum leg extension

[super slim]

What is the optimum leg extension as looking at Maria's photo, she seems to be overextending, but If I could ride as fast as her with that extension, I would do it tomorrow!

On a Double D you could get someone to stand behind you when peddling on a trainer, or back peddling, and if the hips started rocking, then you were over extended, and a plumb bob from just under the knee had to be on CL of the pedal, or just for or aft depending on the riding style.

On the Softrider, or Silvio this is hard to do!

Is there a knee angle and also ankle angle recommended?

Regards

Super Slim

 

[JonB]

Super Slim wrote: What is the optimum leg extension as looking at Maria's photo, she seems to be overextending, but If I could ride as fast as her with that extension, I would do it tomorrow!

On a Double D you could get someone to stand behind you when peddling on a trainer, or back peddling, and if the hips started rocking, then you were over extended, and a plumb bob from just under the knee had to be on CL of the pedal, or just for or aft depending on the riding style.

On the Softrider, or Silvio this is hard to do!

Is there a knee angle and also ankle angle recommended?

Regards

Super Slim

I read somewhere for some other recumbent that you measure it by sitting as far back in the seat, straighten your leg, and then your heel should be able to touch the pedal.

 

[John Tolhurst]

Super Slim wrote: What is the optimum leg extension as looking at Maria's photo, she seems to be overextending, but If I could ride as fast as her with that extension, I would do it tomorrow!

On a Double D you could get someone to stand behind you when peddling on a trainer, or back peddling, and if the hips started rocking, then you were over extended, and a plumb bob from just under the knee had to be on CL of the pedal, or just for or aft depending on the riding style.

On the Softrider, or Silvio this is hard to do!

Is there a knee angle and also ankle angle recommended?

Regards

Super Slim

I guess you could determing the optimum leg length on a DF, then capture that measure in terms of the a straight leg extension and the distance of the heal to the pedal. Then you could relate that measure to the recumbent while you are sitting down.

Caveat: I never am able to properly adjust the leg length while sitting on the bike, I never seem to work myself down into the seat properly and then always have to lengthen things a half inch or inch. I adjust to my comfort. I had the boom gradually creep out while riding once, so after an hour I had some soreness on the back of the legs, then I paid attention to the adjustment and knew it had gone wrong, but it was a frog in heated water thing.

 

[super slim]

I checked the heel to pedal and I could not reach, so I adjusted it back to the original.
Thanks

Super Slim

 

[marshall2389]

Super Slim wrote: I checked the heel to pedal and I could not reach, so I adjusted it back to the original.
Thanks

Super Slim

Its not that simple though. The straight-leg-heel-to-pedal technique is just a starting point. Different riders ride with different ankle angles, which in turn affects the knee angle. Knee angle is what is important when it comes to pain and efficiency. For me, when my knee angle gets to low (too extended), I end up with pain in the front of my knees. When the angle is too high, my leg muscles cannot drain the lactic acid causing fatigue. Use the heel technique as a starting point, then move it around and test it out to find your preferred extension.

 

[charlesw]

I'm finding that as I dial-in

I'm finding that as I dial-in the correct leg extension -- like John, it seems to be out there farther than I think -- I find that my pedal steer is being reduced. I think it might be because if the boom is not extended enough, there is still power in my pedal stroke at the deadspot, which then causes the leftover pedal stroke energy to go into steering.

I extended another 1/2 inch tonight and it seems to have quieted my random unintended steering inputs.

 

[Jim Parker]

I've noticed the same thing.

I've noticed the same thing. Beginning riders tend to have the BB adjusted too short/close. I think this is because when they are setting the boom length, they are pushed way back in the seat. But as we ride and relax more, we tend to scoot forward in the seat, and therefore need a little more length in the boom.

Jim