No hands riding

[Marcela]

Not an ebike, and couldn't find the thread, someone was asking about riding with no hands and I was trying to explain the geometry. This pic is of a bike from the 70s. Note the front fork and the amount of distance the axle is ahead of the head stock bearings. With a setup like this you could ride around town without any hands, and turn corners easily.

 

[Slaphappygamer]

Sometimes, on my ebike, I ride with no feet. Especially downhill.

 

[Stefan Mikes]

Not an ebike, and couldn't find the thread, someone was asking about riding with no hands and I was trying to explain the geometry. This pic is of a bike from the 70s. Note the front fork and the amount of distance the axle is ahead of the head stock bearings. With a setup like this you could ride around town without any hands, and turn corners easily.

Why not try it on an e-bike?

 

[spokewrench]

On a bicycle, that offset is called rake. It reduces trail. Trail is like the caster on a grocery cart. It lines the wheel up with the direction it's being pushed.

Head tube angle is what can make a bicycle self-steering. On a bicycle it's measured from horizontal. Yours seems to have 73 degrees. (On a motorcycle the angle is measured from vertical and called rake.)

When I was 11, I knew of a horizontal pipe 7 or 8 feet off the pavement. I could reach if from the saddle of my English bike. I'd swing out of the saddle and the riderless bike would continue straight until it slowed too much to stay up. If the head tube angle had been 90, it would have fallen as soon as I was gone. It it had been a little less, it might have stabilized itself in a circle. With a little less, it might have overcompensated slightly, to straighten the bike out in a new direction. The head tube angle on that bike was less than that. The steering overcorrected enough to straighten the bike out in the original direction. If the head tube angle had been too relaxed, overcorrection would have sent it swerving back and forth.

I see your seat tube is about 66 degrees from horizontal. That angle is important because without your hands on the bars, your center of mass has to be far enough behind the pedals and ahead of the seat for you to stabilize your upper body fore and aft. On my Radrunner the angle was about 74 degrees. Sometimes I had to lift my left hand to signal. Stabilizing myself on bumps with one hand was such a strain that I got tennis elbow (a torn tendon). Moving the seat aft let me stabilize my weight between seat and pedals so that riding with one or no hands was easy.

 

[Chargeride]

Im always riding no hands,. but not in the wind, the fat tyres act like sails and you get blown around.
Windsteer.
Good name for a fatbike model.
The new Specialized Windsteer.

 

[Marcela]

Why not try it on an e-bike?

I do. Just not as stable as something with more caster.

 

[spokewrench]

Im always riding no hands,. but not in the wind, the fat tyres act like sails and you get blown around.
Windsteer.

It seems to me that the wind would blow the bike around primarily through the rider, being higher and having a bigger cross section.

My fattest tires were the 3.3 inch ones on my Radrunner. Wind or no wind, it steered itself fine at the recommended 30 psi. If I found the pressure down to 25 or 20 psi and aired it back up, I'd notice the improvement.

Once, I reduced the pressure to 10 psi for snow and ice. Back on pavement, riding no-hands would have been impossible because leaning slightly caused the front tire to pull hard in that direction. In a crosswind I would have had to stay tipped into the wind and needed constant pressure on the bars to counteract the pull of the tire. I guess with a fat tire, lower pressure meant a wider contact patch, and tipping the bike would move the center of pressure against the pavement farther in that direction. Maybe a fat-tire bike would behave with a steeper head angle or a different tire construction.

 

[PCeBiker]

,..I guess with a fat tire, lower pressure meant a wider contact patch, and tipping the bike would move the center of pressure against the pavement farther in that direction. Maybe a fat-tire bike would behave with a steeper head angle or a different tire construction.

Self-steer on a fat bike is different.

The contact patch is oval and starts to go concave as the tire pressure goes down.
Then, instead of a flat contact patch, you are riding more on the edges of the oval with the center of that patch not even touching the ground.

Self-steer is one Hell of Weird feeling. It feels like your handlebars are locked or something.


I've always been able to ride any bike no-hands with a bit of practice to get the hang of it for each bike, but the quick-steer of todays bikes are harder to ride.
The steering is twitchy and takes time to get used to.

I ride no-hands over 90% of the time now, and with thousands of km of practice, I've gotten pretty good at it.

Steady wind is easy to deal with and you just naturally lean into the wind, but the gusts can blow you off the road if you're not careful.

I grew up riding similar bikes with the same geometry to what @Marcela posted and I think that was before they "invented" quick steering.

I've always hated quick steering and just found out that I am a Slacker that just got used to a "floppy" front wheel.

I could always flop my wheel around to ride slow up or down hills, but riding a quick steer bike or motorcycle was aways a white knuckle ride where I'd have to constantly force the bike to go where I'd want.

 

[PCeBiker]

I do. Just not as stable as something with more caster.

I've found that my heavy e-bike (as compared to a bicycle) is a little easier to ride no-hands.

The heavier e-bike has more inertia and takes more force to throw it offline. The heavier wheels have more centrifugal forces as the speed goes up that helps with stability and slows down the reaction of my ebike.

I put downhill air forks on my e-bike, and I can plow through 2" deep potholes and barely feel a thing.
When I catch an edge of a pothole, my heavy ebike doesn't react as dramatically.

If I were to catch that same edge on my lightweight bicycle, the edge would grab my wheel and throw it offline in an instant giving me no time to react.
A lighter bike with less inertia and centrifugal force can get tossed around with far less force, and it accelerates offline faster than a heavier bike.


I remember reading about a motorcycle designed to ride the autobahn way back in the day.

The front wheel didn't pivot. It was always allingned with the rear wheel, and when you "turned" the handlebars, the entire wheel would move right or left but still be pointing straight ahead.

The motorcycle had to get moving in a straight line at about 30 mph before the steering would start working, using "Out Tracking" like they teach you in a motorcycle training course.

That would be a very interesting ride to try and figure out.

You probably couldn't ride it no-hands, but I have no idea how to apply math and geometry to it?

I'd just wing it and see what happens, then apply the math later to try to make sense of it.

 

[Chargeride]

Something that is so weird, far more noticeable on a motorbike.
But on two wheels you can go around a left hand bend by steering right or left.
I used to go on long rides on my ZX12 steering around bends by pulling the left bar towards me to around to go around a right bend, and then do the opposite on the way back.
So obvious and well known, but still weird.

 

[PCeBiker]

Something that is so weird, far more noticeable on a motorbike.

I didn't learn about it until motorcycle training class.
Once I started applying it, it was amazing how it worked.

I remember the instructor saying that everyone does it to ride a bicycle but doesn't realize that they are doing it.

Once I learned about it, and practiced, it had a huge impact on my riding skills.

Once you're going about 20 mph, it's all out-tracking with the handlebars barely moving.
I could lean my motorcycle over till I was shooting sparks off my kick stand, but my handlebars only moved about ¼".

 

[spokewrench]

Something that is so weird, far more noticeable on a motorbike.
But on two wheels you can go around a left hand bend by steering right or left.
I used to go on long rides on my ZX12 steering around bends by pulling the left bar towards me to around to go around a right bend, and then do the opposite on the way back.
So obvious and well known, but still weird.

Countersteering. It may be subtle on a bicycle. Supposedly you steer a bicycle by leaning. How do you establish a lean if the head tube angle (rake on a motorcycle) is going to steer the front wheel to bring you upright (as demonstrated when I would swing out of the saddle of a moving bicycle)? To establish a left lean, as you lean, you press on the left bar enough to keep the wheel from turning left enough to keep you upright.

The pre-1970 BMW twins had a very low CG, due the horizontally opposed engines, low frames, and much greater mass than the rider. Suppose you want to lean 45 degrees left. If you shift the weight of your head and shoulders, it will take time to get the bike leaned over that far. If the CG is 12" high, steering the wheels (contact patches) 12" right will establish a lean 45 degrees left almost instantly. Countersteering made those bikes extremely agile, whether or not riders were conscious that that's what they were doing.

About midnight one night in September, 1970, I reached Charleston WV. It was raining. I'd been up 17 hours and on the road 7. I headed northeast on US 19. At the first opportunity, I intended to pitch my tent and sleep. With a low black bike and a low black tent, nobody would know I was there. Hour after hour, there was no place. The highway ran along the east side of the Appalachians. On my left, the ground went steeply up. On my right, it went steeply down. The speed limit was 60 mph, but every so often there was a 15 mph warning sign. Those turns were so sharp that a truck would block both lanes.

About 3 AM, I suddenly noticed I my headlight was shining into a void and I hadn't slowed from 60. Obviously, I'd missed a 15 mph sign. If I hadn't had a fairing, I could have looked down steeply enough to see pavement. As it was, I couldn't see which way the road had gone. For hours, mountains had been on my left and valleys on my right. My headlight was obviously shining out over a valley, so the road must have gone left. I was milliseconds from flying out over the valley. How could I lean into a hard left turn that fast? Countersteering. Slamming the bars hard right snapped the bike hard left. My Avon Safety Mileage Mark II's held in the rain, and I was fine.

 

[Marcela]

Self steering is real nice when going downwind and you grab your windbreaker and pull it up over your head and use it as a sail!

 

[spokewrench]

I used to do something like that coming home from the public swimming pool. There was a steep hill with a stop sign at the bottom. Rather than wear out my brakes, I'd spread my towel like a sail or drag parachute behind my head. It was effective. If the seat tube had been too steep, the jolt could have caused me to tumble backward off the seat.