ESE's works engine tuner

[SwePatrick]

Everone want´s more speed...
So, go the easy way with boost!!
Shuuututututututuuu!!!

A VERY simplified guide:

[ken seeber]

Surely this is the go....high power , low emissions , no expansion chambers....dyno proven...

And here it is: https://www.youtube.com/watch?v=5czHDU6pK8E

Lots of other 2 stroke stuff on youtube under "driving4answers" 2 strokes

[lohring]

As I posted earlier, most of the problems with two strokes were solved a long time ago. The Junkers opposed piston aircraft two strokes were reasonably successful both with their weight and especially with their fuel economy. If you replace the blower with a modern electric turbocharger you get even better power, weight, and economy.

Lohring Miller

[lohring]

A friend built an inertial dyno based on our very successful small engine dyno. Though we had maybe thousands of trouble free runs, he has had issues. Pictures of both dynos are below. Ours is on the bench with the shield.



His problems have been:

Constant failures of the square key connecting the engine to the dyno

Failures of the round shaft he replaced the square shaft with

Slip of the shaft Locktited into the flywheel



The only difference between his dyno and ours is the position of the clutch and the Lovejoy coupling. We have the coupling before the clutch and he has the clutch before the coupling. My thought is that the clutch is a solid connection and in our design the coupling insulates the engine's torque fluctuations from the flywheel's constant inertia better. We never did more than twist the square key. Others with dynos we copied never had any of these problems either.



What are your thoughts?

Lohring Miller

[wobbly]

The only suggestion I have is it seems the failures are all related to torsional harmonic twisting between the crank and the inertial mass.
Those Lovejoy type slotted couplings with varying grades of what is probably urethane pads on the force faces , have to be very hard, or they distort and fail.
Lovejoy also make what are called donut couplings as are used in racecar rear axle assemblies like Formula Ford etc - but I doubt they have something small enough.

Maybe suppliers of mechatronic components for robots etc have a small donut drive coupling , that not only can take axial misalignment, but the rubber coupling itself dampens
torsional harmonics really well.

The other way of doing this is the camshaft drive torsional damper that was invented at Cosworth for the DFV - this has a set of small radial leaf springs that bend back and forth
to insulate the cam drive from crank harmonics.

[husaberg]

The only suggestion I have is it seems the failures are all related to torsional harmonic twisting between the crank and the inertial mass.
Those Lovejoy type slotted couplings with varying grades of what is probably urethane pads on the force faces , have to be very hard, or they distort and fail.
Lovejoy also make what are called donut couplings as are used in racecar rear axle assemblies like Formula Ford etc - but I doubt they have something small enough.

Maybe suppliers of mechatronic components for robots etc have a small donut drive coupling , that not only can take axial misalignment, but the rubber coupling itself dampens
torsional harmonics really well.

The other way of doing this is the camshaft drive torsional damper that was invented at Cosworth for the DFV - this has a set of small radial leaf springs that bend back and forth
to insulate the cam drive from crank harmonics.

as seen on the

Mark IV cortina propshaft up to and likely beyond the seira

Cosworth also used a quill drive on both he v8 and the Norton twin
https://www.f1technical.net/forum/viewtopic.php?t=26642

I think some even used a hollow shaft as Torsion bar
Triumph BSA used one on the points drive on the F750 tripple as the crankshaft tended to whip up and down.

[pete376403]

as seen on the

Mark IV cortina propshaft up to and likely beyond the seira

Cosworth also used a quill drive on both he v8 and the Norton twin


I think some even used a hollow shaft as Torsion bar
Triumph BSA used one on the points drive on the F750 tripple as the crankshaft tended to whip up and down.

Also used for Hillman Imp gearbox to driveshaft joints. AKA Rotoflex coupling

[Pursang]

Surely this is the go....high power , low emissions , no expansion chambers....dyno proven...

And here it is: https://www.youtube.com/watch?v=5czHDU6pK8E

Lots of other 2 stroke stuff on youtube under "driving4answers" 2 strokes

Many of these get posted in the Oddballs and Prototypes thread.

And it looks like our favorite 2 stroke Stuffer has some thoughts about the "Prior Art"!

[lohring]

Re the dynos; It was pointed out to me that our dyno had a very much thicker motor mount. I think it's possible that the engine is moving a lot more with the thin mount and that's what is causing the problem.

Lohring Miller

[Frits Overmars]

................

[Peter1962]

Gelukkige verjaardag, Jan !

Happy birthday

[bad'rule]

Oh how fast time goes by,and already another Happy birthday to our Mr.Jan. Wishing you good health through the year Jan


Sent from my RMX1911 using Tapatalk

[TZ350]

.


Unusual damage to the thrust side of one of the NF4 Honda RS125 pistons that we use in our Suzuki GP110's.

I think it might be that the squish was too tight (< 0,6mm) and the piston was hitting the head while the crank was still trying to go up. There by applying severe leveraging pressure on the piston skirt.

Would be happy to hear other ideas.

[TZ350]

.


Could the tongue on the NSR250 cylinder have caused this, as the piston is rocking over from bottom dead center? Has this been a problem with Honda RS125's? Ideas?

[wobbly]

That piston markup on the dome is all the way round, the width of the squish , so that isnt deto, its been smacking the head big time.
I would say that the crank is flexing - is it a hollow pin or solid - Jan has said that the Aprilia would not hit the head at 14,000 with 0.4 squish.

And no, Honda have used the tongue idea for ever with no issues - and that hole in the piston skirt starts well above the tongue at BDC.
At 0.6 squish depth, and that very wide squish width, what is the MSV in EngMod.