4 in 1 or 4 in 2 exhaust

I was wondering what type of exhaust would give a good overall power/torqeu charastics. Should I use always a 4 into 1 or does a 4 into 2 (like the standard kz1000) give a better result...
I'm running a 1200 cc 0.395 webs and 34mm with a dramaticly Marshall 4 into 1.
I understood you do need some back pressure to keep it running well...

thanks
Martijn

You could probably get as many opinions as there are people on the board. I'll be the first to weigh in I guess. Most of the enthusiasts here seem to prefer a 4 into 1 over the stock exhaust because it gives better scavenging therefore giving more power.
Personally, I prefer my 4 into 2 Jardin system because of the way it's made. Cylinder #1's pipe crosses over so it connects with #4 and goes out the right side, while #2 and #3 connect and go out the left side. This also gives an even pulsing of the exhaust so it scavenges better too.
I guess I just like the looks of the dual exhaust better.
Hope this helps,
Les

The new ZX-14 has a 4-2 for "best" results. A 4-1 may give the most top end but for some middle grunt a 4-2 is less restrictive. I think a 4-1 has a weight advantage more than anythinh else. Especially compared to a stock heavy chromed system.

the 14 has a 4-1-2 I believe

Big advantage of 4/1 over 4/2 is the weight savings.

If I could have my choice of any header I wanted for a KZ, it would be a Murray 4/1. They certainly were not the prettiest pipe made...but boy did those things work..You could even get them with different size primary pipes.

Many of the aftermarket pipes produced during the KZ era did not make more power than a factory pipe. They cut weight and sounded good.

Top end performance benefits from exhaust volume. Acceleration performance benefits from proper wave tuning....

larrycavan wrote:

Big advantage of 4/1 over 4/2 is the weight savings.

If I could have my choice of any header I wanted for a KZ, it would be a Murray 4/1. They certainly were not the prettiest pipe made...but boy did those things work..You could even get them with different size primary pipes.

i love the murry pipes even the x-pipe. i just posted a pick of my dads kz1000ldt in the projects forum. it has one of the old murry 4-1 pipes on it. i have been trying to talk him out of it.

personal i like the looks and the sound of the 4-1 headers but some of the 4-2 looks good to. xpipe are great to.

it seems that they started producing 4 into 1 because they where lighter and cheaper... One whose has ever been moving the 4 original Z900 pipes knows why.
But since I do have the equipement to make my own system I did have the idee of making a 2 into 2 because it looks cool, each side a pipe
I'm not so worried about the weigth.. I am 6feet 8 and the bike weights 240kg...
So you should bring cilinder 2+3 and 1+4 togheter....mmmmm:whistle: gives some constuction problems..

Here is a pic of how the jardine pipes go:


Post edited by: The Milkman, at: 2006/12/01 15:18

The more air fuel you can cram in and the less restrictions getting it out, gives the most power and torque. If the 4 into 1 pipe has no restrictions on the total diameter of the 4 pipes going into it, it should be technically better, because of the weight. As far as I know back pressure is not a good thing on any 4 stroke engine. Only the 2 strokers need it. Back pressure would only restrict the exhaust from escaping, which is a bad thing.

Got a set of 4-2 hooker pipes with a crossover on mine, similar to the milkman's Jardine but the headers cross differently. Great mid range, looks good and sounds even better...

martijn wrote:

it seems that they started producing 4 into 1 because they where lighter and cheaper... One whose has ever been moving the 4 original Z900 pipes knows why.
But since I do have the equipement to make my own system I did have the idee of making a 2 into 2 because it looks cool, each side a pipe
I'm not so worried about the weigth.. I am 6feet 8 and the bike weights 240kg...
So you should bring cilinder 2+3 and 1+4 togheter....mmmmm:whistle: gives some constuction problems..

How would you like some pipe specs for header dimensions?

If you post / pm / email your engine specs, I'll give you the specs on the pipe...

Others can probably explain this better than I can, but the collector size contributes significantly to the engines ability to scavenge effectively. Backpressure in the exhaust system is crucial to good performance at lower RPM - that's why a totally open exhaust system will usually feel very tame at lower RPM.