My Janome MyStyle 16 keeps jamming - thread bunching in the bobbin cavity. Have tried everything but keeps happening... How can I fix this??

Turn your bobbin over. Check your manual to be sure it is loaded correcly. also be sure your bobbin tension is set correctly.

try changing the needle
make sure the bobbin is turned the correct way in the bobbin case
make sure the thread has not come off the thread take up lever
clean under the needle plate and in the bobbin area for lint

I believe that you are talking about the assembly that holds the bobbin case in. The bracket that holds the bobbin case in must be adjusted to allow the upper thread to slide by. Check if the thread will go by this area without "hanging up" while rotating the hand wheel. Also check your bobbin to make sure you have the right one. If it is too high or wide it will definitely be a problem.

try changing the needle
rethread the machine top & bobbin
make sure the bobbin is inserted correctly in the bobbin case
make sure the top thread is not coming off the thread take up lever
make sure the bobbin is wound correctly
if these suggestions don't work, I suggest that you take the machine
to a sewing machine shop to have it checked

when you sew keep a eye on the thread take up lever & see if the thread comes off while your sewing, I've had this happen to me & I've been sewing for over 30 years. if this does happen, take a pair of pliers & very gently close the take up lever just alittle but not enough to damage it.
also check the needle to see if it's damaged--if your not sure change the needle--flat side goes to the back of the machine
always make sure the fabric & needle & thread are compatable--the thread must be able to pull thru the needle with out any problem
also check to make sure there are not any burrs on the needle plate or bobbin or bobbin case

here are my suggestions
1. when your sewing check to see if the thread is coming off the thead take up lever,, I've had this to happen to me & it can jam a sewing machine up
2. it's possible that the bobbin case is worn & needs to be replaced
3.also check your top tension
4. try rethreading the machine top thread & bobbin

have you changed the needle lately?
have you tried rethreading the machine?
when was the last time it was serviced?

sounds like a drive gear or key is sheered

upper tension is wrong or upper threading is wrong (problem is always on the other side of the bunched thread)

Hi, Usually wrap-ups in the bobbin area are caused by the lack of tension on the top thread. The slack arm ( shinny lever that moves up and down while sewing) has to pull the loop around the bobbin case and it does so only if the tension on the top thread is sufficient to keep it from pulling more thread of the spool.
Try this: Thread the top of the machine all the way just short of the needle eye. When the presser foot is up the thread should pull through easily. Now drop the presser foot (this closes the tension discs) and pull the tread while adjusting the upper tension control.
If everything is working correctly you should feel the drag on the thread change if not something is keeping the discs from closing.
Most Janomes aren't too difficult to remove the nose cover, usually just one screw and you can get a look at the thread path. Look for thread wrapped around the mechanism.
Sorry, no easy answer but I hope this helps.