ESE's works engine tuner

[Frits Overmars]

Well, we tried and tried, but couldn't get 70 hp, let alone 30k, so we put a 2nd engine on and it was a lot better. Based on that we are now going over to a 4 cylinder.

I like your sissybar, Ken. Any plans to attach fog lamps? Or a foxtail?

Here's some more inspiration:

Ken, you'll be aware that the regulations stipulate a direct connection from engine to rear axle (that would be the chain), but can you imagine what would happen if the rear axle would accidentally break in the middle (where it happens to be held in two side-by-side bearings)?
Each engine would still be directly connected to the axle, but the wheels would no longer be directly connected to each other. Instead of the inner wheel fighting the outer wheel's grip in the corners, both wheels would work together: less understeer and more grip. And this would allow for softer tire compounds: even more grip.
Talk about an unfair advantage...

[Frits Overmars]

I have seen the video of it (or one like it) running....At 14,000 rpm a complete revolution takes 4.3ms ...

If you saw the same Athena video as me, you will have noticed that it stops at 10,500 rpm .

[breezy]

I would say it sounds like a big bang 500GP doing 13,000 - unbelievably amazing.

wobbly,
could you tell me the major kinds of barriers a 2 stroke engine would have to breach to achieve rpm levels of 30,000, if you had engine components capable of withstanding it? would the engine require forced induction?

[wobbly]

The problem as I see it is twofold.
If you are talking what we regard as "normal" engine technology with rods etc, and these were converted to plain bearing, the next weakest link in line is the ring seal.
At 30,000 and approaching tdc, the ring inertia would easily overcome the gas pressure trying to push down on the ring seal surface.
Then the next issue is simply time,and with what we regard as "normal " pressure ratios across "normal " ports there is no way of achieving any meaningful flow quantity
in the time allotted.
Thus yes, some form of additional time/area is needed or some form of increased pressure differential generation, over and above that created by the virtual supercharger we have inside the pipe.
This is where we are at right now with the new engine being discussed - it must have a non "normal " movement translation device under the piston to achieve 30,000,it must have a different
bore seal arrangement, and it must have some form of additional "supercharge" to achieve 70Hp at 17,000.

[Flettner]

The problem as I see it is twofold.
If you are talking what we regard as "normal" engine technology with rods etc, and these were converted to plain bearing, the next weakest link in line is the ring seal.
At 30,000 and approaching tdc, the ring inertia would easily overcome the gas pressure trying to push down on the ring seal surface.
Then the next issue is simply time,and with what we regard as "normal " pressure ratios across "normal " ports there is no way of achieving any meaningful flow quantity
in the time allotted.
Thus yes, some form of additional time/area is needed or some form of increased pressure differential generation, over and above that created by the virtual supercharger we have inside the pipe.
This is where we are at right now with the new engine being discussed - it must have a non "normal " movement translation device under the piston to achieve 30,000,it must have a different
bore seal arrangement, and it must have some form of additional "supercharge" to achieve 70Hp at 17,000.

I agree ( for what it's worth ).

[Frits Overmars]

It forces you to look at our engines with an open mind, doesn't it?

[Flettner]

It forces you to look at our engines with an open mind, doesn't it?

So we do need to look outside " normal " then.

[jonny quest]

I've asked this before. .. is this engine legal for 125cc kart class racing?

[Grumph]

I've asked this before. .. is this engine legal for 125cc kart class racing?

Given that IMO Kartsport is the most over - regulated form of motor sport on the planet, I'd pick not legal...

And if or when whatever it has is patented, I'd be surprised if that item/mechanism wasn't immediately banned.

[ken seeber]

[QUOTE=Frits Overmars;1130871035]

Ken, you'll be aware that the regulations stipulate a direct connection from engine to rear axle (that would be the chain), but can you imagine what would happen if the rear axle would accidentally break in the middle (where it happens to be held in two side-by-side bearings)?
QUOTE]

Frits,
I’d like to tell you more about the kart split axle programme, but can’t due to the confidentiality agreement we have in place. Nah, just joking.
However, I even had second thoughts posting the pics of the kart. Why? Because, this whole ESE thing is absolutely great, but is primarily about bikes and 2 strokes. Given that, I do have concerns that kart stuff, outside of engines, could poison the thread.
Wob’s made some good points re the time requirement for the gas flow process, particularly so given that it is all happening at 17k, rather than the 12.5k or so with the standard length exhaust.
Prior to the current KF and KZ engines, there were the 100 cc direct drive engines, the last ones featured a tri exhaust and A and C transfers. These revved from 7k to 22k (pretty much self-destruct levels at this speed). The exhausts were a compromise between max power and a useful power spread. It would be interesting to see a power curve of one of these. Husa, where are you?
To go to 30k is pretty impressive, even if it made no power. The force loadings due to the huge increase in acceleration rates are humungous. I suppose one thing a 2T has over a 4T is that during every cycle (around TDC) the piston is cushioned by the compression & combustion, whereas the 4T on overlap goes into tension mode, making the piston, rod, crank etc necessarily stronger to cope with forces in both directions.

Acceleration with respect to crank angle . Formula within this link.

http://en.wikipedia.org/wiki/Piston_motion_equations

Anyone want to chuck this into a spreadsheet? Frits probably has this already. If you do Frits, could you tell us the difference between the max accelerations at 12k, 17k and 30k on a 54 stroke and 110 rod?

Grumph. Overregulation is an understatement. The latest Oz rules (they basically use the homologation documents as the rules) for the latest Rotax Max kart engine (called the Evo) runs to 61 pages. You bucket guys have got it right

[adegnes]

This Ryger case gives me the same feeling as when you find something with your feet in bed, and you try to figure out what it is without looking, but can't.

[Moooools]

[QUOTE=ken seeber;1130871245]

Anyone want to chuck this into a spreadsheet? Frits probably has this already. If you do Frits, could you tell us the difference between the max accelerations at 12k, 17k and 30k on a 54 stroke and 110 rod?

I happen to have this in matlab.
Although I am not sure my math is right as the numbers seem large. The position/velocity/acceleration plots look right but that could be a coincidence.

At 12000rpm - 42620 m/s^2
At 17000rpm - 85537 m/s^2
At 30000rpm - 266378 m/s^2

[Frits Overmars]

This Ryger case gives me the same feeling as when you find something with your feet in bed, and you try to figure out what it is without looking, but can't.

Are you thinking bread crumbs or 36-24-36? In the latter case I can sympathize with you.

[adegnes]

Are you thinking bread crumbs or 36-24-36? In the latter case I can sympathize with you.

Mostly crumbs.

[Frits Overmars]

I've asked this before. .. is this engine legal for 125cc kart class racing?

I've said this before: it's not up to me to decide which questions regarding the Ryger engine I can or cannot answer.