KZ650 4 into 1 without rejetting. Any Suggestions?

So you all may have seen I got a pristine 77 KZ650 over the weekend with original 2 into 2 exhaust. The damn thing is quiet as a mouse. What can i do to make it louder without rejetting? 4 into 1 exhaust? Remove the baffle?

In my opinion if the original 1977 K650 exhaust system is in good condition it would be a serious mistake to try to remove the baffle or otherwise modify the system. The 1977 KZ650 exhaust system was unique to that year; subtle changes were made in 1978. Consequently finding a 1977 system in good original condition is harder than finding hen's teeth. I know because I keep a lookout on eBay and elsewhere for one in case my exhaust system ever is hurt.

If you wish the bike to be louder (I cannot imagine why, but it's your bike) then I would suggest buying a 4 into 1 system and keeping the original system in a safe place. That way when you eventually decide to sell the bike you can offer the original system as an option, or you can sell it right away to fund the 4 into 1 system.

If you keep the stock air box on the bike you may find that rejetting for the new exhaust system change is not necessary. Ed

650ed wrote: In my opinion if the original 1977 K650 exhaust system is in good condition it would be a serious mistake to try to remove the baffle or otherwise modify the system. The 1977 KZ650 exhaust system was unique to that year; subtle changes were made in 1978. Consequently finding a 1977 system in good original condition is harder than finding hen's teeth. I know because I keep a lookout on eBay and elsewhere for one in case my exhaust system ever is hurt.

If you wish the bike to be louder (I cannot imagine why, but it's your bike) then I would suggest buying a 4 into 1 system and keeping the original system in a safe place. That way when you eventually decide to sell the bike you can offer the original system as an option, or you can sell it right away to fund the 4 into 1 system.

If you keep the stock air box on the bike you may find that rejetting for the new exhaust system change is not necessary. Ed

I have to say the original exhaust on my bike is gorgeous, esp with what I believe to be the VIN stamped on it. But its too quiet for the city. I like a louder bike. Maybe I will just leave it.

650ed wrote: In my opinion if the original 1977 K650 exhaust system is in good condition it would be a serious mistake to try to remove the baffle or otherwise modify the system. The 1977 KZ650 exhaust system was unique to that year; subtle changes were made in 1978. Consequently finding a 1977 system in good original condition is harder than finding hen's teeth. I know because I keep a lookout on eBay and elsewhere for one in case my exhaust system ever is hurt.

If you wish the bike to be louder (I cannot imagine why, but it's your bike) then I would suggest buying a 4 into 1 system and keeping the original system in a safe place. That way when you eventually decide to sell the bike you can offer the original system as an option, or you can sell it right away to fund the 4 into 1 system.

If you keep the stock air box on the bike you may find that rejetting for the new exhaust system change is not necessary. Ed

can you suggest any 4 into 1 brands that you may have seen ppl put on their KZ650 without issue?

If I was going to put a 4 into 1 pipe on my bike I would find a Kerker. Here's a video showing one on a KZ650 with stock air box. Ed

Delkevic, they do two styles, made of stainless steel well made, i have one on my Honda 350 four, and a good price as well, will put a video of mine running on here later and a video of the other style. my one is the top one with straight pipe.

Have always been a huge fan of Vance and Hines (and RC engineering) so I went with them but I'll admit a used Kerker in exc condition at a good price would be so tempting ....... I like the Delkevic too but still like the looks of the others slightly more. Z1 has commented and others that the quality of the V&H has gone down over the years and the price has gone up quite a bit too so I'm gonna have to put up with my less than perfect pipe for a while longer.

The only exhaust I've dealt with that didn't require a rejet was a street-baffle Kerker. There are several levels of Kerkers. You want the mildest (quietest and most restrictive) one. It will still run a bit lean,er but you might not have to rejet and still be able to ride it fine after it warms up. That was on a Kz550 which originally had dual exhaust. Even the mildest Kerker is louder than stock and it has a great sound to it.

The Mac system for 550's definitely needed a rejet.

Make sure to store the factory exhaust somewhere very dry, and label what it is (these things have a way of getting lost ).
I wonder if there is a product you can put on for preserving chrome in storage?