Dutchz Z1 road burner - new stuff

i've never seen a KereKer tail that shape , but,i'm likin it bro.
what size is the front end of the tail, and your collector. are they going to match up? i thought u were going way small on the collector?

It's a competition pipe. It was swaged to slip onto a 3" collector, pipe ID is 3". And you're right Mark, I am using a 2" collector with a tapered diffuser out to 2.5" into a 2.5" S bend then mating up to the 3" Kerker tailpiece.
I'll only end up using the megaphone and a small section of 3" pipe of the Kerker.

The primaries welded together with the bullet in place. Bullet is to improve flow and avoid hot spot in collector.

Mocked up with the collector and diffuser cone.

Final mock up on the bike. Gotta work back from here.

I see. u seem to have it all figured out just right. good going Sander. i'm sure u will be very happy with the end results.
What made u deside on 2"? This seems to go away from the norm.

Nice Sander

mark1122 wrote:

I see. u seem to have it all figured out just right. good going Sander. i'm sure u will be very happy with the end results.
What made u deside on 2"? This seems to go away from the norm.

That decision was based on two things:
1. the tuning specs Larry (who did my head) calculated based on my motor/cam combo at desired peak torque RPMs (see below)
2. the feedback I got from the guys at Cone ( www.coneeng.com ) where I bought my exhaust components. Cone said coming down to 2" should help bottom end and placing a transition (diffuser cone) directly behind the collector (rather than a straight pipe) should help scavenging.

For 65.599 CID from 6000 to 8500 RPM

Single Primary Pipe Specs Diameter= 1.052 to 1.177 Length= 23.0 to 25.5 inches long

--- 2-Step Primary Pipe Specs ---
1st Dia. inches= 1.052 Length= 11.5 to 12.7
2nd Dia. inches= 1.177 Length= 11.5 to 12.7
--- 3-Step Primary Pipe Specs ---1st Dia. inches= 1.052 Length= 11.5 to 12.7
2nd Dia. inches= 1.177 Length= 5.8 to 6.4
3rd Dia. inches= 1.302 Length= 5.8 to 6.4

--- Header Collector Specs (Conventional Straight Tube) ---Diameter= 2.017 to 2.267 Tuned Lengths= 13.6 best and also 6.8 or 27.1

--- Header Collector Specs (Megaphone or Diffuser Cone Shape) ---Diameter= 1.517 taper to 2.517 Megaphone/Diffuser Length= 13.6 inches

Best HP/TQ Tuned Collector Lengths= 13.6 , 27.1 , 54.2 , 108.4 inches long

Worst HP/TQ Loss Collector Lengths= 20.3 , 40.7 , 81.3 , 162.6 inches long

Note-> all Pipe Diameters are OD and based-off .0625 inch Pipe thickness

---- Primary Pipe's Harmonics ----
1st Harmonic = 104.4 inches long ... typically never used
2nd Harmonic = 39.1 inches long ... longest recommended
3rd Harmonic = 23.0 inches long ... highly recommended , best Torque Curve
4th Harmonic = 15.8 inches long ... shortest recommended
5th Harmonic = 11.7 inches long ... typically never used
6th Harmonic = 9.0 inches long ... typically never used
7th Harmonic = 7.1 inches long ... typically never used
8th Harmonic = 5.8 inches long ... typically never used

---- Collector's Harmonics (includes Intermediate, Muffler , TailPipe) ----
1st Harmonic = 108.4 inches long ... longest with Mufflers and TailPipes
2nd Harmonic = 54.2 inches long ... longest recommended with Mufflers
3rd Harmonic = 27.1 inches long ... more bottom-end Torque
4th Harmonic = 13.6 inches long ... highly recommended , best Torque Curve
5th Harmonic = 6.8 inches long ... reduced Torque , more top-end HP sometimes
6th Harmonic = 3.4 inches long ... reduced Torque , not recommended

That does look nice.

Mark, It may not be the norm, but the configuration shown here with the 2" small end of the diffuser cone coupled with the larger diameter tail pipe and collector on either side should act like a venturi.

I have all of the same data. what i cant figure out is why no one builds them that way?
i have pondered, through this datain the past, and keep asking myself, why did all of those pipe manufactures then, and now, make them the way they do? everything seems to be bigger, for some reason.i'm not saying anything about if u are right or wrong Sander, just what u already know, this is not the norm. I am very much looking forward to hearing your results. i would have done this myself if i had the resources. i'm glad u are tackling it, Omr is heading down this path as well. i hope u guys come up with a winning formula.
Good luck .
Keep it twisted.

I don't know Mark. Moriwaki makes a pipe that has small collector dia like that, actually I've seen a few high end Jap pipes that appear to have small dia collectors.

Thanks for the encouragement. The cool thing is I have some dyno charts, so we should be able to make a decent comparison!

i can't wait to see how the pipe turns out.are your lower shock bolts built with those spindles on the end?

leon