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Permalink Reply by Carlos Sa on October 31, 2015 at 4:28pm

Upgraded bellcranks? Would you please elaborate?

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Permalink Reply by Roger E Barnes on October 31, 2015 at 7:10pm

Zenith issued new bellcranks some time ago to improve control harmony between elevator and ailerons, which they do with a greater mechanical advantage, but there isn't enough side to side movement in the sticks to make them work.

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Permalink Reply by Carlos Sa on October 31, 2015 at 9:01pm

Thanks, Roger - I hadn't heard of that.

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Permalink Reply by Jay Carter on October 31, 2015 at 9:36pm

     Drill a new hole between existing rod end hole and the lightning hole. Helped the heavy ailerons somewhat. The new bellcrank would not have worked for me as the throw is now leg to leg. 

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Permalink Reply by Roger E Barnes on November 1, 2015 at 7:23am

Quite frustrating to spend two weeks part time and 220 dollars worth parts to find out work has to be redone with original bellcranks.
Consolation I suppose would be for a builder to read this and avoid the time money and aggravation of installing upgraded bellcranks in a 601xl with dual sticks.
Thank you Jay when I get back to this job using the original cranks I will check your idea out.

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Permalink Reply by Bob Pustell on November 5, 2015 at 10:07pm

The bellcrank mod was intended to help lighten up the control feel of the rather heavy ailerons. As already pointed out it does not integrate well with the dual sticks because there is not enough room between legs for the increased control throw.

A builder in Arizona added aileron spades to his dual stick XL to lighten up the ailerons and reported greatly improved control harmony. He also added a small damper/snubber to the pitch linkage to make the too light pitch control feel just a touch heavier. Between the aileron spades to lighten the roll axis and the snubber to firm up the pitch axis he ended up with very balanced flight control feel. I plan to shamelessly copy his ideas.

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