KZ1100 Tire Size

So I am about to order new tires for the bike and was curious if people had any experience upsizing one size over stock ((3.50-19)100/90/19Fr-130/90/16Rear). I went through all the threads and no definitive answer was found. I know there can be issues with messing up tire geometry if you go too big for the rim and pinching the tire and not getting as much contact area. I would like to get a little more rubber under it if possible. Let me know your thoughts.

Going for modern rims with sticky fatter tyres and multipot brakes, yes if you like that sort of thing.

Going up one size works on standard rims works, but you might be trading precise steering for looks.
More than one size up and the round profile gets squashed a bit. One bike I had a 160 on a 130 rim, it was daft.

I know tyres have moved a quantum leap since when these bikes were new, and they were imperial sizes (unusually for a metric bike).

I think back in the day kawi tested these to find the optinum tyre sizes so personally I tend to go by the book. Bridgestone have a recomended size for these models, I tend to go by their numbers here.

Good question worthy of further debate though.

100 front and 130 rear will be fine. The rear wheel is 3.00 wide right? If so you can go even wider, although I'm not sure about sidewall clearance on that particular bike.

130 & 100 are the stock sizes. Rim sizes are 1.85 front and 3.00 rear. I found a chart stating that I could go bigger for both based on rim size but I am finding there is not much for sport style tires for the next size up. Might stick with stock size if that's the case.

Every tire manufacturer will have different specs for their suggested rim size. Typically a 100/90/19 is the absolute largest you should go on a 1.85 front, and 130/90/16 is ideal for the rear but you can get away with a 140 rear. This will distort the profile and make the back mushy. It really comes down to what matters to you; show or go. On a cafe racer I would go with the smaller tire profile as it will have less rotational mass, and not only give you better handling but will make your bike accelerate/decelerate faster

Well if that is the case I will stick with the stock size, as i would have increased all around if possible but doesn't sound like the front has any room to grow without messing with the tire shape. I ended up getting pirelli demon sports in the stock size, lots of good curvy mountain roads around here.

Here's what I did to my 1982 KZ650:
FRONT:
The stock front rim was 1.85" wide; with a stock 100 x 19" tire. The sidewalls bulged outward from the rim. The tire is too wide for the rim, in my opinion, and according to some charts that I found long ago. So I rigged up a rim from a KZ1000, or some such thing, which is 2.15" wide. Brace yourselves --- I then went to a 90 x 19" tire, which is one size smaller than stock. Now the wheel width and tire width are proper. The bike handles so much better than before. It took away that "rubbery" feel when turning from side to side. I used an AVON Roadrunner tire, which has been excellent in traction and longevity.
REAR:
Stock rim width = 3.0" I went from the stock 130 x 16" tire to a 140 x 16". The tire only has about 5 mm clearance on each side inside the swingarm. I've had no problems with this arrangement, but I don't know that it gained anything either. The wheel width would need to be greater for it to be successful. I would probably recommend staying with the stock 130 size tire.