ESE's works engine tuner

[philou]

on the Swissauto where was the balance shaft located ?

[diesel pig]

ktm photos in an album

https://www.kiwibiker.co.nz/forums/a...p?albumid=4857
from what a few have said it was basically a parallel twin with a copy of works NSR cylinders and pipes
it did have a fuel injector to prevent seizing on overrun

Great I have lost my self into the world of Husaberg's Photo Albums.
annoying interesting mind you.

[husaberg]

Great I have lost my self into the world of Husaberg's Photo Albums.
annoying interesting mind you.

i will open them all.
I just opened a few more
There is 10 pages of albums or about 40 or so which is more than the Beatles, but they did write their own material i guess
https://www.kiwibiker.co.nz/forums/album.php?u=28036

[husaberg]

on the Swissauto where was the balance shaft located ?

in the blurb the cases were redesigned to have one my bet is in the bulge above the gearbox behind the cylinders.





https://www.kiwibiker.co.nz/forums/album.php?u=28036

[Frits Overmars]

i will open them all. I just opened a few more.
There is 10 pages of albums or about 40 or so which is more than the Beatles, but they did write their own material i guess
https://www.kiwibiker.co.nz/forums/album.php?u=28036

Thanks Husa, that will help us Northern-Hemispherers through the harsh winter days.
I even noticed an antique version of my FOS exhaust concept (https://www.kiwibiker.co.nz/forums/a...chmentid=32676 ).
It's nice to be in there, but it's a bit outdated now. In case you wish to actualize it, here is the latest version.

[philou]

thank you Husa, I had never paid attention to this growth not present on other engine photos.

[lodgernz]

This sounds familiar
https://www.motor1.com/news/565427/m...hCdFasp_0CM448

[wobbly]

I aked Dr Jeff to post some CAD shots of the new layout.
Here are a couple.

[OopsClunkThud]

Worked with Dr Jeff on the inner and outer profiles of the transfer ports. The inner wall of the ports is the shape of a logarithmic spiral, so the curvature decreases at a constant rate from the port entrance to the exit.

Here's the CAD friendly approximation that was settled on.



This ZIP contains a CSV file that can be imported into fusion 360 for all the equations.
approximated logarithmic spiral.zip

[diesel pig]

This makes me hope some one can post some cutaway drawings or disassembly photos from a KTM 250 GP engine or Dr Jeff could show some basic pictures of Dr Jeff,s project.

I thought after posting this I thought I would be politely but firmly told to go away by one of the regular posters. So the responses I have got have be great!

[husaberg]

I thought after posting this I thought I would be politely but firmly told to go away by one of the regular posters. So the responses I have got have be great!

what i never mentioned was buried deep in one of the albums is a cut away RS cylinder allegedly a Kit one (but aren't they all now.)....Not sure where it was but don't think it was in the RS album?
that took some finding...


Can anyone ID the Honda cylinder it looks Sand cast with provision for RC valve rougher outside than most of the RS stuff i have seen.
But nowhere as rough and workmanlike as the works stuff i have seen? with gernarally is very rough and milling marks casting flash etc on outside.

https://www.kiwibiker.co.nz/forums/a...p?albumid=4394
Not sure why they would bother to put "made in Japan" on a kit cylinder??? although i guess std outer cores?

[philou]

is it the one on ebay that was presented as a Yamaha TZ?

externally it looks like a 4DP of TZ

[katinas]

We meet some guys in Siberia with a jet boat. An aluminium dingy with twin two cylinder twostroke engines, looked similar. We told them through our interpreter the jet boat was a NZ invention. No they insisted, Russian invention. The jet units looked very much like a copy of a Hamilton single stage jet.
All they wanted to do was have a drink with us, Vodka.
Haha, those were the days.

Great story and what a wind blew you into Siberia!!!
I found some other pictures of this engine. Again this 72 mm piston that was used everywhere in Russian engines, motorcycle, tractor starter engines, stationary engines, but actually base is from old DKW engine.
One amazing thing that could be usable for racing from all this stuff, is tractor starter engine dry clutch plates, material is very similar to what was used for racing dry clutches.

Husa, philou, yes this is TZ 250 cylinder. In Husa second picture is actually 1991 3YL cylinder with usual A, B main transfers, but C was divided in two.
DP4 cylinder used from 1992 and B was divided in two, but C narrower and one. Other identification code Y-1 and Y-2 shows port dimensions, Y-2 more tuned with wider transfers (add picture of two for comparison).

[wobbly]

Husa , the left sectioned cylinder is an RS but im sure no one can decipher the codes of factory kit units.
The right pic is a 4DP TZ

[OopsClunkThud]

Another detail on the Dr Jeff transfers.

The outer profile dimensions of the ports are adjusted so that the cross section of the port tapers linearly from entrance to exit.

Here is the approach applied to an (as yet) hypothetical 125 cylinder: