I'm moving some things around on my 2018 Excel U-12.
I'm having trouble getting the 1st string F#-G# raise and it seems the problem is the throw of the particular knee lever, rather than what changer/bell crank holes I use. The lever I'm moving the change to is my LKR, which is non-reversing with the bell cranks mounted underneath the cross rod, (facing the guitar top deck).
The length of the knee lever's travel seems to be determined by the stop screw hitting the edges of the perforations in the aluminum frame. How would you go about adjusting the throw? Swap the stop screw for one with a smaller diameter head?
I thought I'd check in here if anyone has any suggestions before I contact Mitsuo.
I think the long travel required for that pull, combined with the short bell crank (since it's the upside-down one) is creating a situation where you can't get enough pull.
I think that a smaller head on the screw would give you more travel, obviously, or elongating or drilling out the hole would do the same.
BUT, I'd wait for Mitsuo to get back to you - his STRONG mind will have probably thought this out already and have a solution.
A smaller head on the screw would be an easier modification, and not require you to grind on your nice guitar. Fully reversible.
I'd be hesitant to grind on mine.
Another thought is to have the pull start with the screw head hard against the far side of the hole, so that it has maximum travel before it hits the other side.
Make sure you've exhausted all pull rod ratio combinations for the maximum pull first. Then you might consider using a set screw instead of a socket head cap screw of the same thread pitch with some thread locking compound to get more travel.
I am curious why you are having this issue. On my S-10 which I ordered with that change it gets there with no problem at all. It is on the lever which raises 2 and dropping 6 down to F#. The bell cranks as you have indicated are the ones that are mounted on the lower side of the cross shaft and that shaft moves counter clockwise when you engage it.
My pull rod is in the very top hole closest to the body of the guitar. YMMV depending on the what design changer and tuning system is on your guitar.
As per Jim's advice changing the pull rod combination is difficult to say the least. But if you can get to it that would be first suggestion.
I make little hooks out of stiff wire to help guide the pull rod into the holes I want - since it's impossible to get your fingers down there. You can insert the rod from the changer end and use a little hooked wire to lift and guide the rod into the right hole on the bell crank.
Definitely use the changer finger hole that's closest to the body, that will have the most finger travel wit the shortest rod pull.
The bellcrank hole is the one that is closest to the body of the guitar. The pull rod is set to the hole in the top row of holes raises closest to the changer.
