Throttle decelerate lag

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Mustang1964s
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Throttle decelerate lag

Post by Mustang1964s » Tue Oct 24, 2023 5:34 pm

I am sure this has been cussed and discussed many times.
Yes, I have searched and there are a 2k hits on throttle.

I am tooling down the road with the throttle and timing down.
Need to slow down just a little.
Bump the throttle up, nothing, bump up a little more. It seems that it needs to be bumped up way up.
Then the acceleration drop dramatically.

The linkage is not loose but not tight either.
Is this normal? I have learned to live with it.
Just wondering if there is anything that I can do to, to decelerate without dropping way down.

Thank you,

Steve B.

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TWrenn
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Re: Throttle decelerate lag

Post by TWrenn » Tue Oct 24, 2023 5:41 pm

Could be in the carb...maybe the throttle lever on it is real sloppy where it enters the carb. That may attend to the delay.

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Rich Eagle
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Re: Throttle decelerate lag

Post by Rich Eagle » Tue Oct 24, 2023 7:10 pm

Play can be cumulative. The link in the throttle hole, the spark arm hole and the tightness of the arm to the throttle rod all ad to the slop. Also the fit of the butterfly shaft in the carburetor are all suspect. I had looseness in all those places and very little travel until I attended to it.
Rich
When did I do that?


pete eastwood
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Re: Throttle decelerate lag

Post by pete eastwood » Tue Oct 24, 2023 7:30 pm

retard the timing too.


Topic author
Mustang1964s
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Re: Throttle decelerate lag

Post by Mustang1964s » Wed Oct 25, 2023 1:00 pm

I will try retarding and the throttle at the same time.
When I get a chance, I will check the carb shafts.
Thank you for the replies.


speedytinc
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Re: Throttle decelerate lag

Post by speedytinc » Wed Oct 25, 2023 1:22 pm

If running on battery, a small lever retard will be noticed. If running on mag, you must move the retard to the next node before there is any change, that's about 1/3 of arm movement on the quadrant.

As stated, slop magnifies with each joint. Worst is a loose column throttle lever. It must be tightly pinned, a cotter pin wont cut it.
You have that plus wear in the lever hole & rod @ both ends of the rod & a sloppy carb throttle shaft.
Another minor factor could be your compression. Less compression = less motor braking.
A high compression motor is more responsive to backing off the throttle & spark retarding.


Allan
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Re: Throttle decelerate lag

Post by Allan » Thu Oct 26, 2023 2:35 am

John, a tapered cotter pin like the one used to fix a pedal shaft to the axle on a bicycle is certainly up to the job. The trouble is you guys call a split pin a cotter pin. A split pin is not the answer here. :D :D :D

Allan from down under.


speedytinc
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Re: Throttle decelerate lag

Post by speedytinc » Thu Oct 26, 2023 8:12 am

Despite the translation issue, we are on the same page.

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