ESE's works engine tuner

[katinas]

Lovely and shows that Boxer exhaust pipes were not tuned by modern standard.
Do You know power and rpm of Boxer?

Boxers Veterok 70 and Veterok 100
348 cc 70 hp at 9000 rpm
496 cc 100 hp at 9000 rpm

Guseppe Rossi made a very nice engines, its like mix of Konig boxers with Jan's type cylinders and reed valve. Looks like was tested two types for 500 cc, with pairing crank chamber and separated for all four. Paired crank chambers version crankshaft with additional outside bearing to prevent deformation. They still produce 350 cc boxer with unit crank chamber, but on 250 cc base, so its over square bore/stroke like RD 350.
Last year they won WC F 500 with Erko Abrams and F 125 with Sanna Aslav Kaasik.

[philou]

The plates in the crankcase are back in fashion.

crankshaft rotates in the normal direction

[acr]

Always thought a 500VTwin would make a cracking roadbike in the 90s. . . . If only someone made one. . . .

https://en.wikipedia.org/wiki/Bimota_V_Due

[husaberg]

Boxers Veterok 70 and Veterok 100
348 cc 70 hp at 9000 rpm
496 cc 100 hp at 9000 rpm

Guseppe Rossi made a very nice engines, its like mix of Konig boxers with Jan's type cylinders and reed valve. Looks like was tested two types for 500 cc, with pairing crank chamber and separated for all four. Paired crank chambers version crankshaft with additional outside bearing to prevent deformation. They still produce 350 cc boxer with unit crank chamber, but on 250 cc base, so its over square bore/stroke like RD 350.
Last year they won WC F 500 with Erko Abrams and F 125 with Sanna Aslav Kaasik.

JPbiplane wasi nterested in making drones esp boxer ones and posted some stuff ages ago

Any idea what engine is it and specs ~1940 production, used by German military.
Scavenging through piston
Attachment 346564
Attachment 346565
Attachment 346566

Like Niels wrote, it seems to be a boxer with Schliha (spelling!) scavenging through the piston. And the shielded spark plug caps suggest aviation use.
I wonder about the drone application though. Drones were mainly used for target shooting practice, but back then the German Wehrmacht and Luftwaffe had no shortage of real targets.
Attachment 346578 Attachment 346577

[Javier Ruda]

You could drop the cylinder to get enough material above the A port for more axial angle , but then all the ports BDC edges will be low - and alot of extra grinding needed to restore the other ports.
Better to epoxy the A roof with increasing thickness of fill as it goes around the outer radius - this will keep the timing as needed but give you a proven axial scavenging pattern.
You dont need to go to Italy to see the Leaning Tower , we can all have one in our workshop.

Hello wobbly, finally I found some time and disassembled the cylinder from the engine. I measured roof angles using soldering wire, trying to follow the flow direction. Both ports are 17.1º.


Does anybody knows a suitable epoxy for A-port available in Europe?

[philou]

almost any epoxy is suitable.

easily available in Europe. Loctite epoxymatic 3455

[Frank S.]

Does anybody knows a suitable epoxy for A-port available in Europe?

JB Weld, available at Ebay

[philou]

jbweld also works. have seen it often, because many photos of port transfers with epoxy on the internet are made by Americans.

jbweld and available in any hardware store at home. the product is nothing special.

cylinder is made with quiksteel.

knows the preparation with the degreasing that makes the outfit

[katinas]

Other Loctite hi-temp https://www.ebay.co.uk/itm/194709724...UAAOSwGrhh1rLF
And less viscosity for AL repair https://www.ebay.co.uk/itm/113124922...sAAOSwvApaQMyN
I tried both.

Yes Husa, remember this very interesting topic from Oddball pages two years ago. Maybe in theme, add picture from last weekend trip to Trakai city and was very surprised to "meet" this monument. Firefighter engine.

Third picture again boxer for rc models.

[Javier Ruda]

Thank you all for the answers
What a nice forum this is!

By the way, following my new hobby of bending soldering wire, I measured the transfer roof ports of Italkit cylinder for Rotax 122.

They are complete flat!

I guess this is a compromise with the overbore cylinder that they also sell, so that the transfer timings are not lowered on the overbore.

[Frits Overmars]

The plates in the crankcase are back in fashion. crankshaft rotates in the normal direction

I would call it a piston stuffer rather than a crankcase plate. It's usually done in order to reduce the crankcase volume, but it can do some good just the same: it can guide the inlet flow to the transfers, and it creates some pumping of fresh mixture inside the piston, to the delight of the small end bearing and the piston crown temperature.

[Flettner]

Other Loctite hi-temp https://www.ebay.co.uk/itm/194709724...UAAOSwGrhh1rLF
And less viscosity for AL repair https://www.ebay.co.uk/itm/113124922...sAAOSwvApaQMyN
I tried both.

Yes Husa, remember this very interesting topic from Oddball pages two years ago. Maybe in theme, add picture from last weekend trip to Trakai city and was very surprised to "meet" this monument. Firefighter engine.

Third picture again boxer for rc models.

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.

[wobbly]

The Pulse 500Gp project wasnt a lease deal , it was a completely new bike built by the Roberts Team in England - sponsored by BSL and Hacket the bungy man.
The SwissAuto engine had reworked all but copies of factory Honda RS125 cylinders and pipes , it made around 180 Hp , making it as good as anything on track at the time.
Its crankshaft was hugely expensive to make in special materials to prevent failure of the integral pins conected to the common center wheel, and these proved
reliable if religeously lifed and swaped out.
But the engine was very compact and made for very good chassis dynamics.

The question about a V vs a parallel twin has been very well researched by many , and the consensus now appears to fall in favour of the parallel version.
This gives a completely symetric inlet and exhaust layout , whereas the V is always compromised in this regard - when packaged for racebike use.
The KTM 250 GP engine was the best proponent of this approach , with 90* firing and a balance shaft.
Dr Jeff is drawing a 500 version of this with the cylinders turned around and a balance shaft driving twin RV across the front , with gibs etc thus using all available current sota tech.

[diesel pig]

The Pulse 500Gp project wasnt a lease deal , it was a completely new bike built by the Roberts Team in England - sponsored by BSL and Hacket the bungy man.
The SwissAuto engine had reworked all but copies of factory Honda RS125 cylinders and pipes , it made around 180 Hp , making it as good as anything on track at the time.
Its crankshaft was hugely expensive to make in special materials to prevent failure of the integral pins conected to the common center wheel, and these proved
reliable if religeously lifed and swaped out.
But the engine was very compact and made for very good chassis dynamics.

The question about a V vs a parallel twin has been very well researched by many , and the consensus now appears to fall in favour of the parallel version.
This gives a completely symetric inlet and exhaust layout , whereas the V is always compromised in this regard - when packaged for racebike use.
The KTM 250 GP engine was the best proponent of this approach , with 90* firing and a balance shaft.
Dr Jeff is drawing a 500 version of this with the cylinders turned around and a balance shaft driving twin RV across the front , with gibs etc thus using all available current sota tech.

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.

[husaberg]

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.

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