Help! JP15 and JPX Bending Tuning Stability

[PeteRottweiler]

Hey I was wondering if someone who has had a similar dilemma and has overcome it could give me advice on how to fix it.

I just bought a new JP15-7 string. Everything is set up well, the bridge is level and flush with the body, the neck has some slight relief, the intonation is perfect, and the action is good. However, I noticed that when I bend any string (mainly the B and G strings), it goes pretty flat after one bend. Then, if I do a dive bomb it brings the tuning back to where it was before the bend.

After noticing this, I wanted to compare with my old JPX that I’ve had for about 7-8 years now. When testing, frustratingly, it does the exact same thing. I don’t remember it doing this previously, since I bend all the time and I’ve never had a problem. I’ve since changed the strings, lubricated the nut, bridge, and knife edges, but it still has no tuning stability when bending. Also I tested to see if the strings were binding at the nut by blocking the tremolo and doing some big bends, and I had no tuning stability issues whatsoever from this. What should I do to fix this?

TLDR: My guitar goes flat after a bend, and doing a dive bomb brings the tuning back to normal. Lubricating nut, bridge, knife edges, and changing strings did not fix it. Blocking the tremolo and bending a bunch had no effect on tuning, indicating no binding issues at the nut. What should I try to fix this?

 

[DrKev]

Hi Pete, welcome to the forum family!

Just to clarify, you saying the entire guitar goes out of tune after a bend, not just that one string? If it is all strings, that means the bridge is not returning to its zero position after a bend (but after a dive bomb, being a larger motion, it has enough inertia to get back to where it needs to be).

Do you have a bunch of stuff in the trem cavity to dampen the spring noise? If so, remove that and test again.

You have the same behavior on the JPX but never noticed (which means it's not an issue at a practical level). So how much worse is the JP15-7?

Pick up the phone and call Music Man Customer Service, and the dealer you bought from, and ask for advice. If the guitar is new and you're within warranty period.

 

[PeteRottweiler]

Hi Pete, welcome to the forum family!

Just to clarify, you saying the entire guitar goes out of tune after a bend, not just that one string? If it is all strings, that means the bridge is not returning to its zero position after a bend (but after a dive bomb, being a larger motion, it has enough inertia to get back to where it needs to be).

Do you have a bunch of stuff in the trem cavity to dampen the spring noise? If so, remove that and test again.

You have the same behavior on the JPX but never noticed (which means it's not an issue at a practical level). So how much worse is the JP15-7?

Pick up the phone and call Music Man Customer Service, and the dealer you bought from, and ask for advice. If the guitar is new and you're within warranty period.

It isn’t the entire guitar that goes out of tune, just the string that I bent. It was actually pretty bad on both guitars, but I realized that the bridge was not actually perfectly level on both. I didn’t think a slight tilt would matter, but I set both bridges to be perfectly level and the tuning stability is a lot better now (especially on the JPX which has been lubricated). I think if I lubricate the JP15 it should be nearly perfect too.

Thanks for your advice.

 

[StreetLethal91]

Not sure if you got this figured out. One of the things that I learned with my PRS tremolo that transferred to my MM trem system is to make sure you are using as short of a string as possible in the locking tuner. I pull the string tight through the tuner, lock it down, and cut the excess off. Some people like to coil the string around the tuning post a wrap or two and what happens is the coil is stretching causing the string to go flat. If you haven't already, use some big bends nut sauce or graphite on the nut and also a drop of tri-flow lubricate on the knife edge pivot points. Also make sure to stretch and break in the strings really good. I usually go through about 8-9 stretch then re-tune cycles when putting new strings on. One last thing to check is when your guitar is tuned up, check the neck relief. In some cases I have noticed that if the neck relief on my trem guitars is too great it can have an effect on tuning as well. Also, and I know this sounds stupid, make sure the locking tuner is good and tight. My rule of thumb is I get the tuning button tight by hand, then go another quarter turn tight and leave it. I've noticed on the Schaller locking tuners that the locking wheel can sometimes loosen up after strings are broken in. Hope this helps