ESE's works engine tuner

[Muciek]

Words for today nonsmoking 125cc 2t 70HP @ 17-18k rpm

Here's picture

Frits could shed some light on it , but like he said other place he have a confidentiality clause.

[wobbly]

Its got a long rod in it - check the spacer under the cylinder.

[Flettner]

Probably not a picture of the actual engine, I expect that will be hidden for a while yet.

[Frits Overmars]

Probably not a picture of the actual engine, I expect that will be hidden for a while yet.

The internals will probably remain hidden for a while yet, but this is an actual engine. Don't you love it when it looks so simple and so familiar?

[crbbt]

that would go alright in my NX4!

is the powerband very narrow?

[Frits Overmars]

is the powerband very narrow?

Not at all. And that's the last I will say about it for now.

[richban]

Not at all. And that's the last I will say about it for now.

Can you make me a 250 please

[2T Institute]

The engine is a VM 125 ICC kart engine , will be interesting to see what Ryger have come up with 80% less emissions too.

[senso]

70Hp from a 125cc engine, now I feel really dumb, and amazed at the same time.

[wobbly]

As the pic shows the engine in a kart, then we can assume the power is measured at the front sprocket.
The Aprilia did say 55 Hp at 13,000, add 10% for the two gear sets and chain and round to 60 Hp Crank = a BMEP of 16.5 Bar
This engine makes 70, add 10% = 77 @ 17,000 = BMEP of 16.25 Bar.
So all that has been done is to move the same torque level up from 13,000 to 17,000 to achieve the extra Hp.
Of course that is alot easyer to say than do,but we could happily assume there is 24/7 hiding in the front end to help things dramatically.
Though with the piston speed up at 26M/Sec I doubt the 54.5 stroke big end bearing of the stock engine is going to last all that long.

[F5 Dave]

And is it physically achievable to cram enough port area to achieve that BMEP at those revs? That seems unlikely doesn't it?

[Flettner]

Am I seeing things or does it look like two reed systems? One clearly is cylinder reed and if you look real close you can see what looks like a case reed hiding behind the breather bottle thing.

[husaberg]

Am I seeing things or does it look like two reed systems? One clearly is cylinder reed and if you look real close you can see what looks like a case reed hiding behind the breather bottle thing.

I think it has both less than two and maybe even less than one carb operational.
I can also see two entries though.

[Haufen]

Words for today nonsmoking 125cc 2t 70HP @ 17-18k rpm

Here's picture

Frits could shed some light on it , but like he said other place he have a confidentiality clause.

Would you mind sharing your sources with us?

[husaberg]

Would you mind sharing your sources with us?

Right click copy code search as an image using the words.

As the pic shows the engine in a kart, then we can assume the power is measured at the front sprocket.
The Aprilia did say 55 Hp at 13,000, add 10% for the two gear sets and chain and round to 60 Hp Crank = a BMEP of 16.5 Bar
This engine makes 70, add 10% = 77 @ 17,000 = BMEP of 16.25 Bar.
So all that has been done is to move the same torque level up from 13,000 to 17,000 to achieve the extra Hp.
Of course that is alot easyer to say than do,but we could happily assume there is 24/7 hiding in the front end to help things dramatically.
Though with the piston speed up at 26M/Sec I doubt the 54.5 stroke big end bearing of the stock engine is going to last all that long.

One site suggested 23000 rpm............
If Frits is reading as soon as I seen those RPM's I thought of a Scotch crank.
If you recall I mentioned a British project of the late 60's the Excalibur I am almost certain that was to use a scotch crank and some form of moving sleeve.
like I posted on the oddball page recently.


Fridays best use of wood in a two stroke engine
The boost port is blocked with a hand fitted balsa strip. This one has survived a full seasons flying. It isn't glued in just a firm fit in the crankcase.


What the heck i know it will be a glow engine but what the heck........
The slot has been machined exactly 1.15 deep to match with the 1.15mm thick mild steel sheet that I plan to make the shield from



The plug shield is made from 1.15mm mild steel and is 3mm wide by 26mm long. Ideally I would have used 1mm thick but didn't have any to hand. I don't believe that this extra few thou of thickness will make any difference. It is very important that the groove is exactly the right depth for the material used to ensure that there are no leaks. I painted a little bit of Loctite 601 into the slot before pressing the shield bar into it.



The head modifications are finished off by fitting a 0.6mm thick aluminium shim over the steel strip. I coated the mating face with a very thin skim of JB Weld to ensure that the resulting assembly was fully sealed. I chose 0.6mm as I had removed 0.4mm already and needed to put that back and on my other engines I had 0.5mm of shims in addition to the head gasket. I expect to need another couple of shims possibly up to 0.4mm to get the compression back to an ideal setting.

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