How to Pedal Steer

[dtseng]

The feet on the pedals are a lot more efficient to control the direction of the front wheel than the hands on the handlebar. This is the beauty of MBB bikes.
Force is a directional quantity or vector. Force times the perpendicular distance to the rotation axis is the torque. If the pedalling force is directed straight forward, there is a torque to rotate the front wheel. However, if the force is directed slightly side-ward so that , the line back extrapolated, intersects with the steering axis, that is, the perpendicular distance d is zero. That means the torque is zero. This is the reason that the bike is more stable when clipped in. I use platform pedals with studs.

 

[jond]

Heck no wonder I’m a plumber and electrician. Lol.

How come you don’t use clipless peddles on you titanium beauty.

 

[dtseng]

Because I am still less than 12 hours of riding time and I don't want the incident of Larry's first 12 hours to befall on me, ha ha.

 

[jond]

Doing a Larry has become unpopular even to Larry. Still LarryOz offs happen to us all.

 

[billyk]

Speaking as someone who rides no-hands very often, for long distances, and enjoys the hell out of it ... I am still noticeably slower than when pulling on the handlebars in the usual Cruzbike way.

Yes, I do it with the slight outward push on the pedals as @dtseng says, but that is work not moving the bike forward. I find that while doing this, I am rolling my shoulders back and forth against the seat, countering the outward push of the feet with a corresponding sideways push of my shoulders against the seat. Namely, using that friction to balance the sideways foot push. That can't be "efficient".

Further, the big advantage of MBB is the ability to engage the upper body in the forward push on the pedals.

It's still fun, but not the most efficient way to ride these bikes.

 

[bladderhead]

If you push the pedal forwards when it is pointing upwards you are applying torque to the steering-axis. If you push the pedal down when it is pointing forwards you are pushing along a vector parallel to the steering-axis, so no steering effect. Try to put more effort into pushing down. Hard to do this without clips or cleats, though.

I have done the Oslund manoeuvre - well not quite Oslund. I was doing 27mph. Not nearly fast enough to qualify as Oslund.

 

[dtseng]

When I designed my bike, I thought about low head tube angle, something like 65 degrees. Aside from the excessive trail, the pedaling force would produce a torque to make the front wheel lean left and right, much like in the video by karl42 in the thread "how to stop wobbling". In my first iteration, I stick to my DF road bike parameters: head tube angle 72 degrees and wheel base 1028 mm. The result is: I have an easily maneuverable MBB bike.

 

[Charles.Plager]

The feet on the pedals are a lot more efficient to control the direction of the front wheel than the hands on the handlebar. This is the beauty of MBB bikes.
Force is a directional quantity or vector. Force times the perpendicular distance to the rotation axis is the torque. If the pedalling force is directed straight forward, there is a torque to rotate the front wheel. However, if the force is directed slightly side-ward so that , the line back extrapolated, intersects with the steering axis, that is, the perpendicular distance d is zero. That means the torque is zero. This is the reason that the bike is more stable when clipped in. I use platform pedals with studs. View attachment 6924

1) The picture is right. But not really helpful.
2) Yes, you can pedal in such a way that you don't turn the bike. But actually pedaling that way is likely to do bad things to your knees, etc.
3) There are lots of reasons you are more stable when you are clipped in. Your feet being attached to the pedals makes it easier for your legs to absorb bumbs. (Using platforms with studs is ok for most people, but doesn't let you twist your foot at all and this bothers some).

 

[paco1961]

I’m about 1000 miles into CB land. Held off on clipping in until after about 500 mi. Clipped in I’m faster and climb better but way LESS stable. Also find it far more difficult to clip out on my S40 compared to DF. Of course I have the flexibility of a 200 year old white oak 2x4!

One improvement w cleat set up has been pedal spindle extenders of 1cm. Slightly wider Q improved stability considerably.

 

[benphyr]

@paco1961 "Clipped in I’m faster and climb better but way LESS stable." My experience says this is just a matter of time. I am now much more stable clipped in.

"Also find it far more difficult to clip out on my S40 compared to DF." DF has all your weight as leverage, just set the pedal or shoe tension to a lighter setting if it bothers you and it will be comparable.

"Of course I have the flexibility of a 200 year old white oak 2x4!" Wow!

"One improvement w cleat set up has been pedal spindle extenders of 1cm. Slightly wider Q improved stability considerably." Does this mean that your feet are 1cm further out from the centre line of the bike at the bottom bracket and that helped you be more stable? I guess that makes sense - it would maintain higher leg angle from bike centre line which is more stable when standing and it would consequently plant your back more firmly on the seat. hmmm. stability vs. aerodynamics again?!

 

[paco1961]

@paco1961 "Clipped in I’m faster and climb better but way LESS stable." My experience says this is just a matter of time. I am now much more stable clipped in.

"Also find it far more difficult to clip out on my S40 compared to DF." DF has all your weight as leverage, just set the pedal or shoe tension to a lighter setting if it bothers you and it will be comparable.

"Of course I have the flexibility of a 200 year old white oak 2x4!" Wow!

"One improvement w cleat set up has been pedal spindle extenders of 1cm. Slightly wider Q improved stability considerably." Does this mean that your feet are 1cm further out from the centre line of the bike at the bottom bracket and that helped you be more stable? I guess that makes sense - it would maintain higher leg angle from bike centre line which is more stable when standing and it would consequently plant your back more firmly on the seat. hmmm. stability vs. aerodynamics again?!

Your assumption is correct. Each foot is 1cm farther away from center line. Cant imagine much of an aero loss but certainly some. Also allows me to rotate toe out a bit more which helps my knees.

 

[benphyr]

@paco1961 Is there a "standard" width for distance from center line? Is there a way to extend them to test. Probably if there is @LarryOz has probably tried it?

 

[paco1961]

Pedal extension is a funky thing. Most frame makers either recommend agsinst them or say they void the warranty due to excess torque on the frame bottom bracket area. Especially the case for carbon frames.

A major limitation of almost all bike designs is the absence or lack of Q factor adjustability. Same spread for everyone from 5’-7’ tall!

You can experiment w a few washer spacers but it only geys you a few mm

 

[bladderhead]

I have heel-clips made from toe-clips. Easy to get in and out of them. I also have pedal extenders because they let me turn my feet out. If it walks like a duck...

Now you have given me a worry about my b bracket shell cracking. Now I think it is good that my Silvio has the old type of BB clamp consisting of rings that go round the outside. They are as far apart as they can be.

 

[paco1961]

Would love to see pics of the heel clip set up.

Never heard of a BB she’ll cracking due to pedal extenders. I think mostly lawyer induced disclaimers.

 

[bladderhead]

http://cruzbike.com/forum/threads/longer-chainstay-more-speed.12290/page-2#post-144529