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Posted by: mb911 Mar 28 2021, 10:59 AM

As my conversion nears the end I am working on all the odds and ends. I find the throttle is a bit hard to push. If the cable is disconnected there is no issue. I believe the issue is the bell crank area. Its almost as though it needs a spring to assist or a bigger mechanical advantage. Any advice.. ?

Posted by: Mark Henry Mar 28 2021, 11:12 AM

What bell crank are you using?
911 bell crank you have to heat it cherry red, melt the brass and give it a quick turn.

Posted by: mb911 Mar 28 2021, 11:15 AM

Here is my setup.

Posted by: sixnotfour Mar 28 2021, 11:22 AM

accel cable looped over clutch cable ??

Posted by: mb911 Mar 28 2021, 11:28 AM

It could be.. I will have to figure out how to see that angle.

Posted by: Retroracer Mar 28 2021, 02:01 PM

Two suggestions:

1) separate the linkage where the cable ends and make sure the cable/throttle pedal are moving freely and are not snagged or rubbing anywhere (kind of a 2 person job, one keeping tension at etc transmission end, the other pressing the pedal)

2) there are several bell cranks involved in the journey from throttle ending up to carbs - all the links in between should be adjustable for length. This is the key bit: It is worth going through and making sure the sweep of all the angles is maximized over the full range of butterfly rotation by adjusting the lengths of the individual rods; hard to describe without diagrams, but by shortening one link and lengthening another you can make sure each pivot arc is making the longest throw possible, and not "over rotating" on the extremes.

Hope the above makes sense...

- Tony

Posted by: mb911 Mar 28 2021, 02:06 PM

I found it wrapped around the brake line. Its much better now.. not as smooth as I would like but pretty good. I will check the bell cranks etc for max adjustments.