ESE's works engine tuner

[Pursang]

Both cylinders are working (have the same temperature).

I see that the engine has a 1 into 2 inlet & a 2 into1 exhaust.

In the snowmobile world, where these exhausts are not uncommon, it is suggested that the useful rev limit is around 8000rpm.
Beyond that superposition of pulses creates interference between the cylinders.

cheers, Daryl.

[Muhr]

Attachment 342426

Been playing on the dyno again tonight. Green and Red lines are both standard, un modified NSR MC21 cylinders on de stroked rotary valve Suzuki GP100 bottom ends. Everything is much the same between them, timing, heads, pipes etc except the Green line is on a case with much more crankcase volume and fuel injection. Just in case you wanted to know.

Read this a while ago. thought you might find something interesting? maybe further development

http://publications.lib.chalmers.se/...ext/149154.pdf
little more info about the technology
http://www.evinrudenation.com/owner-zone/emm-unwrapped/
http://www.evinrudenation.com/owner-...-bill-grannis/

[jbiplane]

I see that the engine has a 1 into 2 inlet & a 2 into1 exhaust.
In the snowmobile world, where these exhausts are not uncommon, it is suggested that the useful rev limit is around 8000rpm.
Beyond that superposition of pulses creates interference between the cylinders.
cheers, Daryl.

Thanks Daryl, but engine work at max for at least 15 seconds... So probably interference could not be a reason.

[Flettner]

I remember the early years of air cooled bucket racing, power would drop off markedly after the first few laps. I think it was Kenneth Steadman that first smashed the cast iron fins off that little Kawasaki's cylinder, bronze weld a jacket on, similar process to the head, water pump manufactured and fitted to the oil pump drive. Car heater radiator. That little Kawasaki would sing crisp from start to finish. The next year nearly all the buckets were water cooled.
Heat soak and thermal distortion, the enemy.

[Pursang]

Thanks Daryl, but engine work at max for at least 15 seconds... So probably interference could not be a reason.

Dunno, perhaps it takes that long for pipe temperature and wave speeds to stabilise??

Does the exhaust have a perforated rear cone?

Another question to ask: Is the fuel supply to the single carby sufficient to maintain 30hp continuously?

cheers, Daryl.

[jonny quest]

Attachment 342426

Been playing on the dyno again tonight. Just in case you wanted to know. Green and Red lines are both standard, un modified NSR MC21 cylinders on de stroked rotary valve Suzuki GP100 bottom ends. Everything is much the same between the two engines, timing, heads, pipes etc except the Green line is on a case with much more crankcase volume and fuel injection. Interesting that both engines show little bumps in their curves in much the same places.

Is hump your PV's?

Also, loss of bottom end power... do you think that's from case volume... or efi?

[TZ350]

Green line, much larger crankcase volume.

Is hump your PV's?

I put a lot of effort into trying to tune the hump out at 10k rpm with the PV and Ignition but could not get rid of it.

loss of bottom end power... do you think that's from case volume... or efi?

I am not sure about the loss of bottom end power, it was the first bike on the dyno. But I certainly don't think it is EFI as EFI is the easiest thing to get right at wide open throttle. Accuracy of fueling at WOT with two stroke "B" port injection beats a carburetor hands down. Case volume, maybe, but now that I know more about setting up the PV and how low it can go, I will have another look at the loss of bottom end.

[jbiplane]

Does the exhaust have a perforated rear cone?
Another question to ask: Is the fuel supply to the single carby sufficient to maintain 30hp continuously?

Yes, perforated cone
Fuel supply - I see only forum posts related this engine. Now guys trying improve there.
I want make similar inline engine based on 2 cylinders, but make something better than competitor for 115 kg aircraft use.
Hecitate what parts to use:
- 2 sets cylinders of Yamaha YZ85 like https://www.aliexpress.com/item/3301...AbTest=ae803_5
- 2 sets of AM6 90cc like https://www.aliexpress.com/item/3279...22]https://es.
- 2 sets of air cooled Stihl 090 (I have some) https://mikeschainsawshop.co.nz/prod...-piston-kit-2/
- last idea rework Yamaha 2-cylinder outboard using ready crank. piston and sleeves...https://www.aliexpress.com/item/32791606204.html + https://www.aliexpress.com/item/3260...7cf42ceac1i6Es

Looks a bit off-topic, but may be somebody used thise spares in moto-projects and got some preferences/hates...

[jasonu]

I remember the early years of air cooled bucket racing, power would drop off markedly after the first few laps. I think it was Kenneth Steadman that first smashed the cast iron fins off that little Kawasaki's cylinder, bronze weld a jacket on, similar process to the head, water pump manufactured and fitted to the oil pump drive. Car heater radiator. That little Kawasaki would sing crisp from start to finish. The next year nearly all the buckets were water cooled.
Heat soak and thermal distortion, the enemy.

I think the bike you are referring to was called The Rat.

[husaberg]

I remember the early years of air cooled bucket racing, power would drop off markedly after the first few laps. I think it was Kenneth Steadman that first smashed the cast iron fins off that little Kawasaki's cylinder, bronze weld a jacket on, similar process to the head, water pump manufactured and fitted to the oil pump drive. Car heater radiator. That little Kawasaki would sing crisp from start to finish. The next year nearly all the buckets were water cooled.
Heat soak and thermal distortion, the enemy.

I was thinking the same as the chainsaws are designed for forced air cooling with the mag fan and shrouds and they are only used at full revs imminently in operation. chainsaw engines thus tend to have less fins than a fish fillet.
but wouldnt the in this case pusher prop drawa fair bit of cold Russian air over the engine.? i have no idea re aero cooling...........
But maybe in the way its being set up in this situation without a shroud it doesn't?
if only there was a gyro guy./microlight ...........

[Pursang]

The Russian twin aero engine has a cowling & fan



Looks like a lot of development was done.
Don't read Russian so can't tell if this is a design problem or a fault with some individual installations.

cheers, Daryl.

[Flettner]

Disclaimer, I did not do this video. A fellow gyro nut posted it. It's a bit OTT, but it does show that the 700 twin is a real thing and does in fact fly. These are early hours so I'm just using enough power to fly, no where near full throttle, too frightened I'll blow it up. But it goes well.

Jbiplane, I know weight is an issue for you but a balance shaft is nice, at 180 degree firing coupled with this shaft my engine is nearly electric motor smooth and so is water cooling very desirable for sustained high power settings.
Make your own cylinders then you get exactly what you want not someone elses compromise.
https://youtu.be/sm8Y0XWEpIU

[husaberg]

The Russian twin aero engine has a cowling & fan

cheers, Daryl.

What video engine was i watching what i seen looked like an opposed twin?

Disclaimer, I did not do this video. A fellow gyro nut posted it. It's a bit OTT, but it does show that the 700 twin is a real thing and does in fact fly. These are early hours so I'm just using enough power to fly, no where near full throttle, to frightened I'll blow it up. But it goes well.

Jbiplane, I know weight is an issue for you but a balance shaft is nice, at 180 degree firing coupled with this shaft my engine is nearly electric motor smooth and so is water cooling very desirable for sustained high power settings.
Make your own cylinders then you get exactly what you want not someone elses compromise.
https://youtu.be/sm8Y0XWEpIU

i was wondering why it looked like you were in a valley until i got to the end.

[F5 Dave]

Gawd! Looking at the top of those trees made me want to faint..

[Flettner]

Thats why I fly over the gap in the trees. More choices if the engine stops.
Shafts ground and parts fitted.