Cyclocross - What is the widest tire I can run on my Major Jake?

Thinking of doing some epic off-road stuff. What is the fattest tire I can run in the Major Jake frame? I assume the specs are the same as the rest of the Jake series.
Thanks

It depends on what the frame can accept. My Bianchi San Jose can fit tires up to 45C, which excludes fat tires like the Big Apple and Fat Frank. As a compromise, I'm going to put on some Continental City Contact 42C tires, which should be a good all around wide tire.

Man, that is fat! I thought only surly's got into that range. I will look into this some more. Thanks

Chainstys are usually the biggest limiting factor. Measure those. Some forks can clear panaracer fire crosses (45 and super aggressive tead) and a few frames can, though not most.

Also, I like the speedmaxes in 40mm for long distance mixed terrain. Wide, wear really well, and roll pretty fast. Not good in the wet though, and they're heavy wire bead pigs. Most frames can clear them though.

Chainstys are usually the biggest limiting factor. Measure those. Some forks can clear panaracer fire crosses (45 and super aggressive tead) and a few frames can, though not most.

Also, I like the speedmaxes in 40mm for long distance mixed terrain. Wide, wear really well, and roll pretty fast. Not good in the wet though, and they're heavy wire bead pigs. Most frames can clear them though.

Great suggestions...thanks.
I just picked up a pair of speedmaxes in 35 for now. They are super smooth but not as fast as I thought they might be. Of course, I have been running city tires.

I have gotten up to 700 x 42 on my JTS, but it will rub on the chainstays if your wheel is out of true or too flexy. For most of my trail riding with this bike I run the 42 up front and a 38 in back to avoid the rub.