ESE's works engine tuner

[husaberg]

Yes, I am wondering only about the last one. The others seem fine / normal to me.

On the strange head, there seems to have been detonation on the second / middle (yellow) part of the squish. Or maybe there was contact contact after the engine had sucked some sand / dirt / broken off pieces etc.
Attachment 354220

that last outer bit seems to be about the same width as the radiused edge of the flat top.



Oddly the skirt profile appears to be very different from the sculptured skirt of the NSR500 and 250's

nsr500


Bartol KTM


oh i see why

KTM


NSR500




RS125 second on left looks sandcast?
or vapour blasted?

this one has a PV but i guess could be 250



This one below was in my album not sure what RS125 they are nx4 i think according to the name....
one looks like it has been dingle berried .the other au natural



What was this pipe Frits?

[husaberg]

I did find these pics not sure what they are as the don't appear to be named but kind of look tz ish
https://www.daemo.de/Race/HH125.html


On the same site one for the fans of Honda 50's

.......

this one is another disc valve one


https://www.daemo.de/Race/Honda50.html

[jonny quest]

Who's going to buy one and cast their own cylinders?

https://www.ebay.com/itm/36419101130...mis&media=COPY

[Frits Overmars]

What was this pipe Frits?

..........

[skako]

Hi, Frits
is there a link somewhere to explain these abbreviations Lt, Lsz, iso, nL, nD, nT.
I suspect they are related to the variable pipe length and resonant rpm.

[Frits Overmars]

Hi, Frits
is there a link somewhere to explain these abbreviations Lt, Lsz, iso, nL, nD, nT. I suspect they are related to the variable pipe length and resonant rpm.

Not a link as such, but I will try to explain if you promise to refrain from asking follow-up questions; at the moment I am too involved in design work to formulate answers.
Lmax is a no-brainer: from the exhaust port upper timing edge to the throat of the end cone restrictor.
The whole end cone, from its maximum diameter to its minimum diameter, plays a role in reflecting the stuffing pulse. Somewhere along the end cone(s) is the 'center of gravity' as it were, of this reflection. Lt gives the position of this center.
Lsz is a percentage of Lt; it does for the suction pulse what Lt does for the stuffing pulse. I've found that around 0,425 is optimal
iso represents the rate of temperature loss from the pipe to the outside world. The default value is 1. But as an example, a boat engine that wets its pipe with a rooster tail of water can drop its iso to 0.8.
nL is the optimum rpm for wave resonance.
nD is the optimum rpm for Helmholtz resonance.This value is strongly dependent on the header diameters.
nT gives the optimum value for the end cone restrictor. However, for you guys I recommend using the restrictor diameter D5 calculation in my simple FOS exhaust concept below.

[skako]

thank you Frits

[wobbly]

Last November I ordered the English version of the Jan Thiel book, this had not arrived by end Dec and NL Post had no tracking data for it.
So I asked Jans friend who is doing the postage to look into it , and said as nothing had been scanned he would immediately send another.
Anyway , unbelievably both books arrived today , the first I opened and now cant put down , the other is still sealed in its envelope.
I promised to pay for the second book whenever it arrived , so in good faith Im offering it here to a NZ address for what it cost me.
If you want it ,DM me and it will be on the way.

[jamathi]

Last November I ordered the English version of the Jan Thiel book, this had not arrived by end Dec and NL Post had no tracking data for it.
So I asked Jans friend who is doing the postage to look into it , and said as nothing had been scanned he would immediately send another.
Anyway , unbelievably both books arrived today , the first I opened and now cant put down , the other is still sealed in its envelope.
I promised to pay for the second book whenever it arrived , so in good faith Im offering it here to a NZ address for what it cost me.
If you want it ,DM me and it will be on the way.

I am happy it finally arrived, hope yo like it!!!

[F5 Dave]

Pm sent Wob.

[JanBros]

@ Jan : shame about the last 250 WC lost to Aoyama; 50 titles sounds so much better than 49. or were you already retired and it wouldn't count ?

[p12palof]

@12palof

Your cr 500 ...what is your purpose you are aiming for?

A 500 cc will never reve easily high... especially if you have less blowdown as needed


21 degree on the bottom rpm is possible as you increased the msv of quish

You set ignition to 15 degree at 8000 ...realy?
Cant beliefe 8000 is peak power at old reed 500cc engine

My guess would be peak much under 8000...

To much advance after max power / running out of breath surly kills every free reving..

One way for first shot to set timing at peak power is to look where is peak in datasheet from original bike...

Your exhaust duct / flange...are there steps inside to the header ?


Edit...please google for "cr500 vhm dyno tests"

Peak of cr500 is about 5500... and "on pipe" is lower than 4000...

Have made a quick and dirty ignition curve that should fit to cr500 ...only for a first shot and maybe your next dyno run..i bet fits better...please let me know

If you need the tunebox file...let me know too

Grüße Wolfgang

Hi Wolfgang, thanks for the help. My CR500 is tuned. That´s the reason because it´s peak around 7800 rpm. Stock it´s peak around 5500-6000. The stock timing is around 178/122 and actually in my bike is 192/126. The CPI exhaust was "intended" for drag races in dunes... with the objective of maximum peak power only in mind. This bike is not confortable in stock condition. Tuned is also uncomfortable but at least it has more revving capability.

My objective is to improve the shape of the power curve, maintaining the revving capability. I will test your ignition curve, as soon as I put the bike on dyno. At this moment the bike is dissambled for maintenance.

[wobbly]

Thanks for the messages guys , the book sold in about 30 seconds.

[Wos]

Hi Wolfgang, thanks for the help. My CR500 is tuned. That´s the reason because it´s peak around 7800 rpm. Stock it´s peak around 5500-6000. The stock timing is around 178/122 and actually in my bike is 192/126. The CPI exhaust was "intended" for drag races in dunes... with the objective of maximum peak power only in mind. This bike is not confortable in stock condition. Tuned is also uncomfortable but at least it has more revving capability.

My objective is to improve the shape of the power curve, maintaining the revving capability. I will test your ignition curve, as soon as I put the bike on dyno. At this moment the bike is dissambled for maintenance.

Ok... you have blowdown enough...then my ignition is not helpfull

But set 15 degree on your measured peak...not later...and do dyno

Then do a dyno test with setting 15 degree before last measured peak...lets say 1000 earlier... and you get a new peak...can compare both ...see whats better for overev

Overev can also be maintained by how steep and deep your falling of timing after peak is...secret there is to produce high exhaust gas/ pipe temperatur within a given length of pipe..

Have nice dyno runs! �� and Let us know

Grüße Wolfgang

[jamathi]

@ Jan : shame about the last 250 WC lost to Aoyama; 50 titles sounds so much better than 49. or were you already retired and it wouldn't count ?

I was already retired, in 2007.
Unfortunately Simoncelli broke his wrist 2 weeks before the season started...