78 kz400 straight pipe?

Can I run straight a pipe on this thing? I still kinda want to keep it 2-1 but weld some kind of straight pipe on it. Is this possible? Re-jetting? I know nothing about exhaust systems. I want something like what is on this bike... oh and I have pods..if that matters. and I want this bike to be loud!

I'd imagine you could. It would really mess up your jetting though (either too lean or too rich because of a loss of back-pressure). A lot of people say straight pipes are bad for your exhaust valves and whatnot, but Id just go with what sounds good to you and if you're willing to deal with rejetting constantly until you have it right. I was dealing with the same issue not too long ago when I straight piped my kz250; I had an aftermarket carb and pod on it and when you combine that with a free flowing exhaust system it created a headache of a jetting issue. In the end I swapped back to the original carb but it's still running lean. Also if you want to save some money, go to a good muffler shop that works on performance cars and bikes; I only paid $10 for a full fabrication and it looks on par with most factory pipes.






Here's some more info on straight pipes if you're interested: ( pnwriders.com/motorcycle-talk/157714-straight-pipe-bad-not.html )

Good luck!

Yeah just like yours is how I want it!! What kind of exhaust is that and what size? Thanks for the input btw. I have mine chopped almost all the way down to where the 2 pipes connect and still runs decent. a little lean though. I know Im a fool for doing that but I just wanted it louder.

justwannaridekz250 wrote: I'd imagine you could. It would really mess up your jetting though (either too lean or too rich because of a loss of back-pressure). A lot of people say straight pipes are bad for your exhaust valves and whatnot, but Id just go with what sounds good to you and if you're willing to deal with rejetting constantly until you have it right. I was dealing with the same issue not too long ago when I straight piped my kz250; I had an aftermarket carb and pod on it and when you combine that with a free flowing exhaust system it created a headache of a jetting issue. In the end I swapped back to the original carb but it's still running lean. Also if you want to save some money, go to a good muffler shop that works on performance cars and bikes; I only paid $10 for a full fabrication and it looks on par with most factory pipes.

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Here's some more info on straight pipes if you're interested: ( pnwriders.com/motorcycle-talk/157714-straight-pipe-bad-not.html )

Good luck!

Would you know what size jets I would need by any chance?

That pipe in the pic actually has a muffler on it. I had something somewhat similar on my 750, but dunstall style. Here is a list of universal ones.
www.jpcycles.com/motorcycle-mufflers/j-and-p-cycles

I think you might be disappointed when you hear what the bike will sound like with a straight pipe. I had a honda cb500 with straights once and it sounded like a pissed off lawnmower. Could probably save some cash and time jetting just cutting your stock muffler off and mounting one of these - you can switch baffles in and out of some of them and even wrap them in fiberglass to get the sound/performance you're looking for.

It's just some exhaust pipe they had laying around; all they did was bend it and weld a little tab so it could mount onto a secure spot. Pipe size is: 1 1/2 in (inside diameter) and 1 3/4 in (outside diameter). It has a great sound to it and a lot of harley guys are jealous because my little thumper is louder than their v-twin's. Are you running stock carbs and have you rejetted for pods yet?

Also, here's a video of my bike if interested: ()

justwannaridekz250 wrote: ..... It has a great sound to it and a lot of harley guys are jealous because my little thumper is louder than their v-twin's...

Ha ha ... I doubt it! LOL

Stock carbs and no rejetting has been done yet. It seems to run fine but since I chopped the exhaust back quite a bit already I heard I still need to rejet because I lost a little low end snap. Seems like I gained a little in the top end though I just need to know what size jets to step up to. Ive done plenty of research but keep getting different answers. Ill post some pics and a video of it later today.

justwannaridekz250 wrote: Are you running stock carbs and have you rejetted for pods yet?

Will any of these be loud? I dont want loud and obnoxious Harley loud but want it to sound somewhat mean lol

apbling wrote: That pipe in the pic actually has a muffler on it. I had something somewhat similar on my 750, but dunstall style. Here is a list of universal ones.
www.jpcycles.com/motorcycle-mufflers/j-and-p-cycles

I think you might be disappointed when you hear what the bike will sound like with a straight pipe. I had a honda cb500 with straights once and it sounded like a pissed off lawnmower. Could probably save some cash and time jetting just cutting your stock muffler off and mounting one of these - you can switch baffles in and out of some of them and even wrap them in fiberglass to get the sound/performance you're looking for.

I just added the dunstall ones to my 750 4 cylinder - made it a little louder, but changed it more to a deeper growl, but sensible and not embarrassing - like when ppl are looking at you because you look and sound like a goofball rather than them looking at you thinking "wow that bike sounds cool!".

I wouldn't think a 400 would ever be super super loud. I have straight pipes w/ no baffle on my honda 1100 twin, and yes its loud, but there are harleys that are louder than me (they should be with 300-400 more cc's). But I'd recommend some sort of muffler because it'll make jetting easier and be better for your bike overall. On the plus side... in my opinion, these small displacement bikes just don't sound good with pipes, hence why I still and always will have my stock exhaust on my 550. But those slip ones did add a nice growl. Heres two vids of my 750 with them on. You'll have to watch a different video to hear the stock sound. I just cut my old rusted cans off, slaped these on with the help of a reducer from autozone and all I did was richen up the pilot a touch. No jetting and no real performance differences.

Also, there are a TON of videos on youtube of your bike with different exhaust. some sound bad ass, some not so much... should help you figure out what you're looking for

Loud bikes are a disservice to motorcyclists everywhere because they create ill well with the general populous. It's incredibly selfish to run loud pipes and inflict your noise on everyone within earshot. It's hard enough to get respect from cagers as it is, and loud bikes give people a very good reason to disrespect bikers and their rights.

A KZ400 is pretty much a dog slow bike anyway. Slow and loud is a bad combination. Reminds me of guys running a loud fartcan on their Honda Civic.