ESE's works engine tuner

[jamathi]

How much different was the jetting between pipe testing for brst optimization Jan? Are we talking needle tapers.... 1 to 2 mainjet sizes? All of the above plus more?

Between 220 and 225 main jet size.

[jamathi]

Jan whats the paper stuffed in the cylinders for?
i noticed its also in the pic with the cylinder comparsions that (i think Riley Will) posted once.
Attachment 330895
Edit It might have been Frits i can't recall.

The paper describes what has to be done with the cylinder, after inspection:
replate, hone, or fit a bronze ring after detonation.

[husaberg]

The paper describes what has to be done with the cylinder, after inspection:
replate, hone, or fit a bronze ring after detonation.

Cheers Jan

[41juergen]

Here is the RV inlet inputs.
The Exhaust port itself was already made smaller, as Jan had begun experementing with lifting the floor, but my comment about size was more directed at the duct exit area.
Simply using EngMod and shooting for a duct exit Mach of 0.8 the result is a huge jump in power when reducing the Aprilia flange area and creating a new transition within the spigot.
The duct length, including the spigot was also increased slightly to 2X bore and the pipe adjusted accordingly.

Thank's a lot Wob for sharing...

[Makr]

Anyone know how these turned out?

Attachment 330891

I want to see how they attached the two pieces.

[tedspeed230]

No.

Not depending on the bore, but on the stroke/bore-ratio.
Attachment 330479

There is no difference in the porting of the late-model RSW and RSA cylinders.
But the RSA has better cooling (channels inside the inner curvatures of the transfer ducts) and two extra head studs that somehow contributed to power.
Attachment 330480

Sorry if Iam missing the obvious but what is ATN in your scavenging angle concept?Using 54 bore works out for a and b ports but the c port comes out at 76 deg against a previously quoted 50 deg.
Thanks
Neil

[Frits Overmars]

what is ATN in your scavenging angle concept?Using 54 bore works out for a and b ports but the c port comes out at 76 deg against a previously quoted 50 deg.

ATN is the standardized abbreviation of the inverse trigonometric function Arctangens:
https://en.wikipedia.org/wiki/Invers...nctions#arctan
Any pocket calculator worth its batteries should be able to help you on your way with it Neil.

[Flettner]

KTM 300, note the injector placement.

https://www.facebook.com/motostation...5289746293996/

YZ250

[teriks]

KTM 300, note the injector placement.

https://www.facebook.com/motostation...5289746293996/

Looks familiar

[Frits Overmars]

KTM 300, note the injector placement.

They took a good look at your engine Neil .


(click on the pics 3 times)

[husaberg]

They took a good look at your engine Neil .


(click on the pics 3 times)

(Second pic) barbed brass pipe above reed valve?
i don't recall any mention of it being posilube,so is it a pressure sensor feed?
In the facebook video https://www.facebook.com/motostation...5289746293996/ it appears to go to the fuel tank, but that's presumably where the pump is located, so maybe rising rate regulator?
Flets fuel rail is far more snazzy as well

[Frits Overmars]

i don't recall any mention of it being posilube

It is posilube. The pump is electric, the oil is contained in the frame top tube. http://adbmag.com.au/editorial/ktm-u...d-two-strokes/

[teriks]

(Second pic) barbed brass pipe above reed valve?
i don't recall any mention of it being posilube,so is it a pressure sensor feed?
In the facebook video https://www.facebook.com/motostation...5289746293996/ it appears to go to the fuel tank, but that's presumably where the pump is located, so maybe rising rate regulator?
Flets fuel rail is far more snazzy as well

My guess is that the oil line goes on the throttle body, and that the pipe on the cylinder is indeed a pressure senor feed.

[tedspeed230]

ATN is the standardized abbreviation of the inverse trigonometric function Arctangens:
https://en.wikipedia.org/wiki/Invers...nctions#arctan
Any pocket calculator worth its batteries should be able to help you on your way with it Neil.

Thank you Frits its all clear now.

[Juho_]

Hello,

I've been developing a Minarelli Am6 engine for 'some time' now.. and currently it has +5mm stroke (44mm, bore 39,90mm) = 55cm3.

On previous cylinder I reached less power, but higher peak bhp rpm (around 13-13,500rpm) and about 14,800rpm max rpm with E85 fuel and with and without heat wrap on exhaust pipe.

The differences to the current cylinder / motor are cylinder capacity, port timings (only slightly, but way more blowdown and transfer port area, and much, much better transfer ducts), larger crankcase volume (now at 305cc @ TDC including transfer ducts - I have understood, that the transfer ducts usually are not included in crankcase volume..haven't measured them yet) , exhaust duct and adapter to pipe, which are a lot smaller (the adapter also shorter .. yes, I know, not good, makes the exhaust duct also shorter...which is approx. 50mm, and it was ~75mm...sadly I do not remember, what was the previous adapter and exhaust duct diamete or areas..but do remember that, they were much larger)

The question is, what I have been thinking.. could the exhaust duct / adapter be too small because of it's reduced size and cause the much lower peak bhp rpm, which is currently at around 11,000-12,000rpm.. when adjusted very lean at high rpm - it's at ~12,000rpm.
On rich side it may go even below 11,000rpm.. fuel change did not effect, like it has previously done -- neither did retarding ignition timing (I do not have an EGT meter).

I'm asking your opinion, because I ran out of argon, so I'm not able to TIG weld a new adapter and do more modifications for the cylinder.

Pipe is indeed way too long for the engine (830mm including exhaust duct length). But it does not explain the difference.
(yes, I'm going to fabricate a shorter pipe, when I have time and argon)


And sorry for my bad english ! I hope you understand, what I mean.
Thanks in advance !