Can I leave speaker jumpers in?

I wouldnt leave jumpers in as no benefit to biwire cable. It should only take seconds to put jumper in. But do a listening test as if you can't hear difference then don't bother 

I’m trying the jumpers in, even while using BiWire cables.  Initially a little more laid back presentation.  Using MIT Magnum jumpers with MIT REV 60 cables.  Fun experiment!

Realize already that the definition, detail, air and space that I heard before the jumpers were put in is gone!  Bad idea 👎 

I’ve purchased another pair of bi wired cables so I won’t have to mess with the jumpers. Thx to all for your helpful input.

Try this, if possible; 

If you have enough jumpers with the right terminations, you can double them up. Doubling jumpers (absolutely parallel) is very efficacious. I do not use jumpers and bi-wire at same time. If you have jumpers with spades and jumpers with banana terminations, that can work well, too. 

Then, you can double up the speaker cables (absolutey parallel, no crossing over from L to R!) to one set of speaker posts, along with jumpers, single or double. There are more permutations on basic jumping available than most audiophiles realize.  

Options, which will all sound different:
Single wire to either set of posts (try both) and jumpers
             "                                                     and double jumpers 
Double jumpers; double speaker cables (parallel) to upper posts
           "                                                        lower posts

BE CAREFUL! CHECK YOUR WORK! Make one mistake and you can blow your amp, and perhaps hurt your speakers. This is not the time to be hasty or careless! 

You will be surprised at the differences between these methods. AWG is very important. I do these kinds of builds all the time.  :) 

Then, if you really want to advance things, look into the Schroeder Method of Interconnect Placement. Do your own due diligence on that, as it is a do at your own risk maneuver.