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post #1 of 14 (permalink) Old 10-14-2013, 05:09 PM Thread Starter
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Jerky throttle

Ever since I've had this bike (and through 2 carb rebuilds) I've always found that when I roll the first bit of throttle one while the bike is in gear it comes on with a jerk. The rest of the throttle range is smooth, just coming off idle jerks if in gear. Is this somewhat normal?

-Robert
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post #2 of 14 (permalink) Old 10-14-2013, 05:35 PM
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throttle jerking? or clutch jerking as released?
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post #3 of 14 (permalink) Old 10-14-2013, 05:36 PM
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Quote:
Originally Posted by RobertGary1 View Post
Ever since I've had this bike (and through 2 carb rebuilds) I've always found that when I roll the first bit of throttle one while the bike is in gear it comes on with a jerk. The rest of the throttle range is smooth, just coming off idle jerks if in gear. Is this somewhat normal?

-Robert
I don't know what it is, but it is not normal. It may not be the carbs. Since you said it does this with it in gear, it might be something wrong with the transmission or final drive, like it is taking up lash in the drive line when the rpms increase.

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post #4 of 14 (permalink) Old 10-14-2013, 05:58 PM
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Does it make a little noise at first?does it do it when warmed up?

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post #5 of 14 (permalink) Old 10-14-2013, 08:27 PM Thread Starter
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No, no noise. I probably didn't explain it well. So if I'm decelerating in gear, not touching the clutch and then want a bit of power, if I roll on the smallest amount of power it comes on with a lurch. After that I can continue to advance the throttle and further acceleration is smooth. Its just that first bit when its under load. Its definatly not clutch or transmission related; it feels like the power just doesn't come in smooth. It feel more like when your 15 year old is driving the car and you say 'give it a bit of gas' and they give it too much and you get somewhat thrown in the back of the seat. My bike has always done this and I assumed it was normal.

-Robert
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post #6 of 14 (permalink) Old 10-14-2013, 08:46 PM
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Inner cable inside throttle housing may be crusty. When it reaches certain tension suddenly releases take of and relube or replace maybe.


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post #7 of 14 (permalink) Old 10-15-2013, 08:41 AM
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there is a certain amount of 'play' or 'slop' in the transmission and rear gears.. including the rear splines.. normally not much, but as the bikes get older and wear, just like a car, when you go from the coast side of the gears, to the drive side, there may be a jerk.. that might be what your feeling.
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post #8 of 14 (permalink) Old 10-15-2013, 10:45 AM
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If the throttle is harder to turn just above idle, I'd say it's a frayed cable, or cables. Just saw some cheap on Ebay.

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post #9 of 14 (permalink) Old 10-15-2013, 11:09 AM
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agreed Spockster.

if all is smooth in the throttle assy, I would look elsewhere
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post #10 of 14 (permalink) Old 10-15-2013, 12:33 PM Thread Starter
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Quote:
Originally Posted by jadabull View Post
Inner cable inside throttle housing may be crusty. When it reaches certain tension suddenly releases take of and relube or replace maybe.
That's definitely what it feels like. However, if I have one hand on the throttle and the other on the carb I can't feel any binding as I roll the throttle on. It feels really smooth. The bike only has 15K miles so I wouldn't think the gears would be worn.

-Robert
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