Herky - Jerky Throttle Response

[redbirds_imp]

Strange, throttle response on mine is very linear, way better than the two fuel injected Triumphs I had and better than my wife's V-strom.

Could chain or throttle cable slack be a factor?

[Scoobynut_imp]

Here's my reply from the older thread:

I've found that the throttle free play on almost all modern bikes is set very loose from the factory, so I tighten it up to almost, but not quite, zero play, so that as soon as the throttle is turned it meets resistance. If that play isn't reduced you have this 'dead zone' of turning the throttle very easily, and then sudden resistance that is hard to guage exactly where it begins. By tightening the play, you are much more in control of throttle engagement. It makes being smoother much easier IMO. Within a few miles you will be used to the earlier throttle engagement. This completely eliminated any jerkiness in my CB1100, and has worked great on my other bikes also. I believe it was Greg who mentioned in the other thread that a loose throttle won't cause this on a FI bike and that may be so, but I still think a tighter throttle is just easier to modulate and control than a loose one.

I should mention that the above is in combination with having your chain slack set within factory spec, with the caveat that the CB11 seems to be less jerky when set toward the tighter side of the factory spec.

[HondaJon_imp]

She's too lean from the factory. PC V makes a huge difference, even with stock exhaust.

[lackskill_imp]

Mine was due to chain slack being almost double spec on delivery... Once I adjusted it properly, it's as smooth as any modern injected bike I've been on.

[Tortuga_imp]

Mine was due to chain slack being almost double spec on delivery... Once I adjusted it properly, it's as smooth as any modern injected bike I've been on.

Where does Herky-jerky come from?

[CB4ME_imp]

Mine was due to chain slack being almost double spec on delivery... Once I adjusted it properly, it's as smooth as any modern injected bike I've been on.

Where does Herky-jerky come from?

Websters says the word is a reduplication of "Jerky", first used in 1957 (to describe......?????)

[lackskill_imp]

Mine was due to chain slack being almost double spec on delivery... Once I adjusted it properly, it's as smooth as any modern injected bike I've been on.

Where does Herky-jerky come from?

Where does Herky-jerky come from?
chain slap. The slack in the chain will literally transition from top to bottom or vice versa depending on which throttle transition.

Think of it like pulling on a rope. If the rope has slack in it, you'll experience very little resistance followed by a sudden jerk. If the rope has no slack the resistance is linear and immediate.

The acceleration jerk is the transmission drive gear pulling on the chain and taking up the slack. The deceleration jerk is because of the final drive gear pulling on the chain and taking up the slack.

[HikerToo_imp]

You can tell the difference between drive train play, and RPM drops and surges...you can't fix what the PCV does by tightening a chain or throttle play, its different.

[Tortuga_imp]

Mine was due to chain slack being almost double spec on delivery... Once I adjusted it properly, it's as smooth as any modern injected bike I've been on.

Where does Herky-jerky come from?

Where does Herky-jerky come from?
chain slap. The slack in the chain will literally transition from top to bottom or vice versa depending on which throttle transition.

Think of it like pulling on a rope. If the rope has slack in it, you'll experience very little resistance followed by a sudden jerk. If the rope has no slack the resistance is linear and immediate.

The acceleration jerk is the transmission drive gear pulling on the chain and taking up the slack. The deceleration jerk is because of the final drive gear pulling on the chain and taking up the slack.

Where does Herky-jerky come from?
chain slap. The slack in the chain will literally transition from top to bottom or vice versa depending on which throttle transition.

Think of it like pulling on a rope. If the rope has slack in it, you'll experience very little resistance followed by a sudden jerk. If the rope has no slack the resistance is linear and immediate.

The acceleration jerk is the transmission drive gear pulling on the chain and taking up the slack. The deceleration jerk is because of the final drive gear pulling on the chain and taking up the slack.

Ok, thanks I feel bad now, I wasted your time explaining the symptoms to me.

What I was asking is where the EXPRESSION 'Herky jerky' came from.

[wayne van horn_imp]

I think it came from watching a dance where the person was acting like a turkey. they called it the herky jerky turkey dance.