Do you still think I should change them, even though Race tech says otherwise? Anybody else?
For what you are wanting out of your suspension at your weight I don't see any need to change your springs. I am 6' 5 270 lbs and I have been able to get everyone of my bikes stock suspensions to work just fine on the street. First thing you need to do is find the stock settings for your suspension both front and rear. It will be in your owners manual or a shop manual. If you don't have either of these you can look here for a good base setting. Sport Bike Motorcycle Suspension Settings - Sportbike Review - Sport Rider
The list only has up to the 06 CBR1000 but it should be the same for 07. This is just a base anyway to get you started.
Once you have done this then you need to check your suspensions sag. This will make sure that your suspension has plenty of travel to absorb bumps as well as handle dips without bottoming or topping out. There are serveral ways to set sag on a motorcycle but for the street I have found after 18 years of riding that the zip tie works the best for the front and I do the rear by feel. For your forks take a zip tie and wrap it around one of your forks just below the dust seal. Then take the bike for a ride. Make sure you do a couple of hard stops and ride the bike like you would on a daily basis. This will put the forks through their full range of motion for your riding style. Then check to see where the zip tie is on your fork. I find that 8-10 mm above the end of the fork works best for me. It gives me plenty of suspension travel but leaves a 8-10 mm cusion just in case I hit a really bad bump, pot hole, or have to make an emergency stop. The last thing you want in any of these cases is for your suspension to bottom out. If the distance between the end of your fork and the zip tie is more than 8-10 mm then decrease your preload. If it is less then increase your preload.
As for the rear, I start by setting the preload so that the rear of the bike squats about 30-35 mm when I sit on it. I don't take a measurement or anything like that I just have a feel by now for how much the bike should sag when I sit on it for my riding style. Then I take the bike out a for good ride and adjust the preload on the shock until I find a setting that I like the feel of. Once you have your sag set where you like it then you can start fine tuning the suspension to your liking with the rebound and compression settings. Whatever you do get a note pad and right down your base settings, any changes you make to them, and how the suspension reacted when you made the adjustment. Then you will be able to go back and look at your notes to see what worked for you and what didn't. Then it will be easier to dial your ride in.
Now I know what I have just posted isn't a racers method for the perfect setup up for a motorcycle suspension and I am sure I will get flamed for it but for everyday riding like what you are looking for it is the easiest and most effective way I have found to get a stock suspension setup up for a decent ride on the street.
A few other things that can help a motorcycle absorb those bumps is tire choice and riding style. For the type of riding that you like a good sport touring tire may give you a smoother ride, longer tire life and still have plenty of grip to let you get a little crazy in the twistie sections. As for your riding style you should be gripping the tank with your thighs and holding yourself up with your stomach and back muscles. Your arms should also be slightly bent and keep a lose grip on the handle bars. This will allow your arms to act like suspension and make your ride a lot smoother. You can also use your legs to help handle some of the bigger bumps. You don't have to stand up on the bike but you can slightly raise yourself up off of the seat when you see a big bump ahead.
Now if you decide one day that you want to get more aggressive on the street, your stock suspension is up for this task to. The key to making it work for you is smooth throttle and brake action. A rider with a smooth right hand on a stock bike can out ride a ham fisted rider on a race bike any day. Your throttle and brake have a huge effect on how the bike transfers weight thus effecting how your suspension handles.
All of this being said, a stock suspension has no where near the capabilities of a good race suspension that is setup for your weight but if you are not looking to shell out extra money for your suspension then it is more than capable of handling everday riding with in the legal limits of the road and then some.