I got this back from TImney when I emailed them the other day. It sounds like with the heavier hammer they might be able to fix that!
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The current Gen is Gen 2. Late Sept 2015 we will come out with Gen 3. The difference between the two are the hammer and the dimensions. Gen 2 does not fit all IWI Tavor rifles. IWI changed the dimensions on their rifles in Jan/Feb this year, so our Gen 3 will be compatible will all older and newer model Tavor rifles.
We are currently waiting on the heavier hammers. Once we receive those back from heat treating, we will replace the hammers on any returns we have that experienced that issue. All Gen 3 and Gen 2 made from this point forward will have the heavier hammers.
If your Timney Tavor trigger model #680 works in your rifle, you are fine. If you ever experience any difficulty, we will take care of you right away. All you have to do is send the trigger back to us. We will repair or replace it if needed. You do have a lifetime warranty on all your Timney triggers, and our aim is to repair/replace and return the trigger to you within 24 hours of receiving it. So you won’t be left without for long
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