I’m 6’4″. I have been racing for 11 years and I have driven quite a few of the chassis brands available. There is not a chassis for “tall people” and there doesn’t need to be. It’s mostly about setting it up for your height. Seat position is critical and once you get this right everything else will fall in place. The only concern you might have is the need for an extended front porch to move the pedals forward if they are too short for you. Most manufacturers support this option. I used to run an extended front porch and now I do not. It’s a very tight fit but I have made some modifications to make it work for me.
That being said I have had the most success in the past couple of years on my DR Kart. It has worked very well for me and responded extremely well to setup changes despite my height. If you are looking for a personal recommendation from a fellow tall racer this is the chassis I would suggest. They are also recent world champions as well!
I would strongly suggest getting a used chassis to start with until you really get your feet wet. You won’t need a new frame if you are just starting out. You might check with Pole Position Karting in Frisco, TX to see if they have any used karts in stock. Feel free to PM me if you have other questions.
I agree with Chris above. I’m not as tall (6’1″) or as fast as him but most guys can make it work without an extended porch. I tried an extended porch on a CRG and I hated it. The extended porch gives you more leg room, but you end up with your feet sitting on top of the front rail, which lifts your toes higher in the air. In addition, the front bumper and nassau panel all move forward. I didn’t like it at all. I’m on a DR Kart as well, and I put the factory DR seat real close to where it was recommended from DRT racing. It is tight, but it works great and the kart handles amazing. On another note, since your taller don’t immediately think you have to be on a 32mm frame. I thought the same for a few years, then finally went to a 30mm DR kart S97 and I wish that I would have tried one sooner. I highly recommend the kart. If you are still looking, I know of a couple very good condition S97 shifters that are for sale. Send me an IM or email and I will put you in touch with the owner.
I’ve been racing for 17 years, I’m 6’3″ and never had to use a special chassis or anything. You just need to know how to set up the kart. Set the peddles far back, remove the foot rest thing a lot of karts come with now. Raise the steering wheel til it’s comfortable. Make sure the seat is low.