if you run straight pipes on your bike will there be enough back pressure? And is it legal?

legal probably depends on where you live:-)

Definitely not in California and the rest of the country is starting to crack down on noise compliance as well. Thats always one excuse they can use for pulling you over, so if you don't mind the added attention you will get go for it. The type of pipe you run also depends on what you are running in motors and setup. Lowend, highend what are you after etc?

All States have a noise law, so the opens will most likely be illegal. (though I have seen plenty of them on the road)
Most States have EPA regulations, some strickter than others. Most aftermarked pipes do not reduce emmissions so that would be a problem. (Though, again, a lot of us run then)
Back preasure is the issue. If you put open pipes on almost any bike it will lose power unless you re-jet or re-map.

Does anyone have a line on a really good place to get slip-on exhaust for a 07 1300 4cylinder Yamaha Royal Tourer Deluxe. If you do get in touch with me. A have been searching with little luck.

EPA is a federal law, it's up to the state to enforce it. Although many states try to enforce it many never provide the DB level which makes it instatable, PA is one of those states. Although the can get you on the tequnecal of no EPA stamp, that falls under an equipment violation not an illegal situation for anything else. The law is tricky and you have to navigate through your rights, all laws are open ended so there is room to play with the legality of statute laws and federal laws but do you really want to is what you have to ask your self!

Well put on the legal issue Hoz.

For the back pressure... as with any major exhaust system change you will need to have the bike re-jetted or re-mapped. I would recommend using a high flow air cleaner because the open exhaust will want to suck in more air, and then have the carb, EFI tuning done.

Less an issue of if is legal or not is weather or not the local authorities enforce it. Here in SoCal, straight pipe are everywhere and about the only place you have issue is in the City of IRVINE and a few other spots in the Orange County (Lucky might be able to expand on that, it's his neck of the woods)

As for emissions....unless the changing of pipes has a significant effect on your engine performace (lack of back pressure causing loss of engine performance) the emissions issue is negligable at best...the pipe itself does not reduce emmissions, it only has an overall effect on the performace of the engine itself, which is where the emissions are created. If you change pipes and then re-map or make what ever adjustments to your ENGINE that are needed to put it back on the top of it's curve, crap out the tailpipe will not change, might even improve over stock. This is the fight that is constatly being brought to the various states where aftermarket pipes are the target of various do gooder organizations. Join ABATE or another MRO and help fight the fight!

Never have ran straight pipes,yet I have known a few guys who did, & its really loud!!! as for engine performance/backpressure that shouldnt be an issue until you open up the airbox,then from what I have learned it requires remap on fuel injection or carb adjustment.One issue with the above usually is decel popping & backfiring hence the fuel/air adjustments are required.

Looking at the bike you have listed on your profile, other then the carb changes you maybe all set. I have a old 76 Ironhead sportster that I run straight pipes on and if fires up fine.
The legal issue is one up to you. I just passed on having the bike inspected and rode it like it is. It funny how may even new bikes up here don't have inspection stickers on them.

Are the inspection stickers mandated by the state your in? we do not have a inspection set up out here,and I would be reluctant to do one if it involved the govt spending my hard earned dollars on more bureaucratic red tape to discriminate against motorcyclists in general?

I run Vance & Hines Straightshots on my 01 Aero. I was going to take the baffles out, but the sound coming from them almost split my skull with the baffles IN. Definitely get it re-jetted any time you change pipes or it won't run worth a damn.

i am running 1 3/4 straights on my shovel with an S&S Super E carb and yes there was some jetting needed when i made the change it was minor and the sound was WELL worth it.

I run the Vance n Hines Cruzer II 's on my 750 Aero . I pulled the baffles out and it actually hurt my ears' so I re-installed them. Its still loud enough to suit me.

i cut my custom chrome exhausts off right where the pipe went from 1 3/4 to 21/2- because the removable baffles were 12 inches long- and i could not get the baffles out- i then installed 4 inch baffles inside the pipe to provide some back pressure -(i hreard i would destroy the valves fast if not) -- also running a screaming eagle aircleaner and carb - rejetted as well - the sporty can make some racket now- but i will say the loud pipes have made my visable in traffic- and therefore - i will never ride a quiet bike-
torque cones are also available to provide back pressure

Pipes? Well, anytime you change the back pressure to the engine you will need to re-jet the carbs or possibly change the injectors if you have injectors.

Legal issues? Well, I've been in Texas for a while, although, when I was inspecting bikes in PA, no modification to an exhaust system, excepting only after market replacement parts, meeting OEM spec are legal (rarely enforced or rejected by an inspecter unless ur in the shop of a smiling, authorized, official OEM sales organization). In New York State, where I started riding, the noise level was, at that time, regulated by the Conservation Dept. and anything above three decibles could be enforced and that included your brew and bean farts. Besy way not to piss people off is to put baffles in your pipes and one up your ass. What can I say.