I am currently running stock flexifoil barrows. Want to upgrade to the midi. I have found several at local stores (central tractor, etc.) What is the difference between a tire that has a crown on it or one that is very flat on top. I see that many members talk about Carlisle tires..do I have to buy that name brand? Smooth ribbed or one with tread? Mostly flying in horse pastures and soccer fields.

The midi's will give you a bigger contact footprint. On the beach it will help a good bit, on the grass, it may make it a little easier to slide around because of the profile. The sidewalls will not "roll" as much when you are turning in hard or putting a lot of pressure during a good pull on the grass! Not sure but we may have a set, I can check!

Yes please check, I would much rather purchase all my things from PKF Members who are always helping me out. Will these make my buggy ride a little nicer in the bumpier fields if I run the air pressure a little low?

Maybe a little! I will check in the morning and get back to you!

I usually buy the more rounded tires, but the width of your rim will determine how rounded the tire is.

I have found that Carlisle tires have thicker treads and last quite a bit longer than the generic Chinese tires that are a bit cheaper. I think I heard that Carlisle tires are being made by another brand now. Sorry, don't know that name right now.

The wider the tire on grass will equal more friction and drag. Not that this is a negative thing, but you will most likely finding yourself having to size up a kite than if you were on the standard barrow tires. When I ride on grass with bigfoot lights instead of barrows I need to size up atleast 2m larger because of the resistance of the grass. Not all turf is the same so depending on how thick, long, etc. your results may vary a bit.

I'll second Dino's observation. It won't be so much of an issue if you ride on thin scruffy grass. Thick and lush will bog you down worse with the wide tires as well as them be squirmy on top instead of steadily cutting through the grass.

I would also agree on that observation, knowing his smaller than myself stature not sure it would slow him down that much at all. He's probably 40lbs lighter than me.

Just to confirm. I am looking at a 16 x 6.5 x 8 tire. I have found 2 styles that match this size. One looks like an oversized version of the stock wheel I am already running. The other is very flat on top. Almost concave on the top as it sits on the shelf (not mounted) to the wheel. I am thinking that once tube and air is in it, it will flatten out more. When I say flat, it's like you could put a 2x6 board on it and the rubber would be touching the entire surface of the wood.

I am not big...150lbs. and my flexifoil is at the smallest setting on my downtube.....if you were talking about my size for kite pulling??

I think I'd go with the 'oversized version' of what you are running now. I think the flat top version has a quite aggressive tread which might tend to grab when cornering hard on turf, flipping you over maybe? BTW, have you ever flown at Fairhaven Beach State Park? It looks like it might be fun on a N wind.