Friction zone + rear brake = stable bike?

[ill'n]

When I'm coming to a stoplight and I know it will turn green soon I sometimes get lazy and, instead of putting feet down, will try to slowly coast (~1 mph) until the light changes. I used to coast by pulling in the clutch lever all the way, but this resulted in wobbling the handlebars in order to stay balanced. I've noticed, however, that if I keep the engine at just-cracked-open, the clutch in the friction zone, and engage the rear brake to hold back the bike, I can still travel at the exact same 'slowly coast' speed, but the bike is extremely stable. I don't have to wobble the handlebars anymore.

Why is that? I can't think of any physical explanation. It's not because the bike is faster -- it's the same speed as before. It's not because the wheels are acting as gyros -- again, it's the same speed as before.

Has anyone else experienced this phenomenon, or am I just crazy?

[Flak Monkey]

Rotational forces in the engine helping to moderate the bikes movements? That's the only explanation I could think of, but I haven't tried doing this yet so I'm not sure it will even work for me.
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Battlestar Galactica Forum

[Derail]

because clutch pulled in means theres no power going to the wheel. When you just use brakes you go the same speed but you are still sending power from the bike to the ground. In msf they tell you that power to wheel keeps you stable, its not only speed. same things as giving it a little gas in a corner instead of coasting, you can make it but its more stable to give it some juice.

[Flak Monkey]

because clutch pulled in means theres no power going to the wheel. When you just use brakes you go the same speed but you are still sending power from the bike to the ground. In msf they tell you that power to wheel keeps you stable, its not only speed. same things as giving it a little gas in a corner instead of coasting, you can make it but its more stable to give it some juice.

The reason that you don't off the gas in a corner is that your suspension will settle giving you less ground clearance.
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Klonopin Rehab Forum

[Erg0n]

I was told it had something to do with physics. Think of the bike as a rope, the rear brake pulls the rope from the back and the engine pulls the rope from the front causing tension which in turn keeps the bike from wobbling at low speeds

Or something along those lines, I wasn't really listening, this was before we were doing the straight line at slow speed exercise on our bikes and tried to do it without the rear brake.

[ill'n]

because clutch pulled in means theres no power going to the wheel. When you just use brakes you go the same speed but you are still sending power from the bike to the ground. In msf they tell you that power to wheel keeps you stable, its not only speed. same things as giving it a little gas in a corner instead of coasting, you can make it but its more stable to give it some juice.

I agree with Flak Monkey, power in corners help because it stands the bike up so you have more clearance, it also compensates for the shrinking of the effective circumference of the tire because the bike is now running on the side of the tires which have a smaller radius, and finally it distributes the weight more to the rear tire which is usually wider and thus have more grip.

But as for rollong slowly in a straight line, none of the above consequences of power seem to help the bike be more stable.

[ill'n]

I was told it had something to do with physics. Think of the bike as a rope, the rear brake pulls the rope from the back and the engine pulls the rope from the front causing tension which in turn keeps the bike from wobbling at low speeds.

Rear brake affects the rear tire, and engine "pull" also transfers through the rear tire. So the push-pull effect is only happening on the rear tire, not the entire bike. Too bad, because that would have been a very elegant explanation.

[Nibblet99]

My understanding is its gyroscopics in the engine, helping to keep you upright... This is also the exact slow control method we are taught in the UK, for maneuvers

[Apollofrost]

+1 to gas in the corners. If had gassed it I wouldn't have crashed.

[slimcolo]

I never heard of "friction zone" till last week. After further research it's just another case of a new name for an old concept. We used to refer to this as riding the clutch.