A bandsaw is the right tool, and pushing wood that size through it isn't any big deal.  Any tool like a sawzall or jig saw will have trouble staying straight if you try cutting all the way through. 

You might have the best luck by running as deep as you can with your TS saw on one side only and then finishing the rest with the recip saw.  There will be more material to cut, but you won't have to try to line up two TS55 cuts.

I know an arborist who has a bandsaw (industrial like) to cut felled trees into planks.  Who knows, there may be one in your area.

I think that's the right approach (the hand saw). You should be able to get the remainder down to just over an inch, right?

heck, you might even be able to split it apart at that point!

Haven't seen one commercially available that's that large, but there's nothing keeping you from building one.   There was an article on Gary Katz's site a while back about cutting huge moldings, and basically the author just created a three-sided box- bottom and two sides- and sliced notches in the sides to guide the handsaw.  I'm thinking it ought to take about $5 in material and 10 minutes to put together.

This is the best way if the top and bottom are not parallel. If they are reasonably parallel
I'd go ahead and use the circular saw from both sides.

To finish the cut with the recip saw I'd roll the wood over and snap a chalk line and saw
from that side (opposite of the circ saw kerf).The reciprocating blade should be long enough
that it stays in the kerf for the full stroke. To help keep the blade in line with the circ saw kerf
I'd dull the teeth of the end of the blade so it rubs in the existing kerf without digging in.

I'd take the wood to a lumber yard and pay them $20 to mill the timber for you. This is what I do when I have a board that is to big for me to handle, such as a 17" tabletop that was too wide for my planer.

Usually they charge by the hour and are happy to help.

More great suggestions, thanks!

I tried cutting 1 kerf and finishing it with the sawzall and that was very slow going.

This gave me the idea to use the sawzall cut to line up the rail on opposing sides of the beam. This worked ok on the beam I tested - the sawzall was cutting a lot less material and maybe I was lucky and the two faces were relatively parallel.

On the cross-cutting - I completed a project about 18 months ago where I was cross-cutting these using a Prazi beam-cutter attachment on my Dewalt framing saw. The rental place near me had the Makita beam saw, but their blade needed to be replaced. The Prazi did ok, but I was constantly adjusting the chain tension, lubing the chain, etc - it got through the job ok, but I was constantly worried it may break.

I opted not to go with the makita for resawing because at some point I would be balancing a 16 inch diameter saw on 1.5 inches of material as I was slicing away boards. Sounded hinky, so I stayed away from that solution.

Well, that was fun!  Thursday was day 2 of ripping those 6x6's of old red oak.  They were measuring approximately 5 3/4" around, definitely not today's 6x6.

I should have tried a real rip blade in the TS75 as the stock blade labored and kept blowing his breaker.  My Bosch worm drive framing saw (similar to the Skil 77) did it but went a lot slower than I had thought it would.  Surprisingly to me, the TS55 with the rip blade was quick and smooth.  Interesting experience trying out the different saws and this just goes to show you, how much of a difference the blade can make.

awdriven (true identity concealed  ), great to meet you and your family, again!  See ya soon!

You're very welcome.  I guess this means the driveway is clear as there's no parking in front of a mountain of dirt.