EXHAUST LEAK

So I pretty sure I have a exhaust leak on one pipe.  My question is I have a delkevic 4 in one exhaust to I nee the two piece exhaust collar or just the replace washer gasket?

The seals are the "crush" type.  Did you replace the old ones with new when you installed the pipe?  Sometimes it's hard to get the pipe to seal even with new seals and some KZ folk use Suzuki GS seals because they are thicker.  On my 750 I used new seals supplemented with some additional fiber gaskets I cut.  Bottom line is to do whatever it takes.

I installed a 750E muffler system onto my 650-CSR & wasn't sure if they fit perfectly, so I used Permatex high temp red rtv supplemental to new exhaust gaskets. I didn't gob the stuff on. I put a little on one side of the gaskets & let them sit a few minutes to cure a little, then put them in the ports, then put a little more rtv on the other side of the gaskets, wait a few minutes again, then install the mufflers. Let the gasket sealant fully cure before running the engine. Of course, thoroughly clean the exhaust ports beforehand & make sure there aren't any old gaskets stuck in there. you never know sometimes.

ps: reuse the half-moon exhaust collars.

Yeah the exhaust came with knew ones when I installed the exhaust. but took it off when I had a top end rebuild.  the exhaust pipe on the left side I can feel the heat pipe right around the exhaust port.  other three are good. I only ask because the collars are like 5 dollars a piece and I need 8. vs 4 crush washers that will cost me 10 bucks for the set. plus I only install the crush washer the first time.

I don’t have a Delkevic system, but typically you need both the collars and the crush washers. I have read about folks reusing the crush washers after annealing them, but have never tried it myself.

I'm assuming you retorqued the nuts?

You should use new crush washers every time the exhaust is removed.

I replaced mine with the KZ type from Z1 last time and they seem good but wish I would a got the Suzuki ones.

Will next time. Talked myself into staying original but in this case I think it would be better for the thickness.

I did try to tighten alittle but not much. What are they suppose to be torque at? order new washers and sleeves from z1. install them and see what happens

Use the GS ones - they work.

I went 16 ft.lbs with the Suzuki gaskets. They were finger tight after the first run. Gotta re-torque .

1st of all, new DELKEVIC exhausts come with their brand of copper crush washer. They are .171" thick.
Stock aftermarket cheap crap on net for Kaws are .120" thick.
Plus Delkevic supplies silicone RTV for sealing also.
Delk; does not need collars!
ME: I have been using red high temp RTV, since it came out 25 years ago for sealing exhaust pipes. My old Shovelhead has never had a gasket on it's exhaust. That cheap old Harley design with 1 - ]5/16" bolt?. I use RTV on them. Have for years.
Plus if you crush down a washer, get a new one!
Or on the cheap, seal it up with RTV silicone!
Don't know what size your exhaust studs are? But be careful with the early 6mm studs.
Kaw learned and went to 8mm on 77 and up big KZ's