ESE's works engine tuner

[Frits Overmars]

... It is way better rideable than the old one... The difference in the two powerbands responds from different compression ratios, the old was 15:1, the new 9,5:1.

When somebody wants to know how you managed to improve the engine so much, feel free to tell the truth; no-one will believe you .
(Well, I will).

By the way, did you join that german forum we talked about? If so, what's your nickname?

[TZ350]

Hello guys. It´s me again. Maybe you remember me from page 1082.

There is some new stuff I want to show you. I have done some machining on the cylinder, the head and I built a new exhaust (slightly different dimensions).



I was able to gain 0,5rwhp but the more important fact is the bandwidth after peak hp. It is way better rideable than the old one, because the hp don´t drop too fast (old dotted blue, new one red, both hp at the real wheel)



The difference in the two powerbands responds from different compression ratios, the old was 15:1, the new 9,5:1. I am satisfied with my engine and in the moment I don´t plan to change something on it.

Riding video:
https://www.youtube.com/watch?v=49X465mPmHM

Some stuff I built:
https://www.facebook.com/EPsimson


Greetings from Germany
Lucas

I very much like the extra cooling fins that have been added to the crankcase and the improved power curve with the lower compression ratio is very interesting, food for thought, thanks for showing us.

Team ESE are working on RG50's and courtesy of Kel (drawings) and Sketchy (machining) we have heads with inserts.



I remember Frits suggesting to me to try a lower ratio so when I get my own 50 going I am going to explore lower compression ratios and try different head shapes too, thanks again for showing the results of your work.

[Larry Wiechman]

What is at work here? The lower compression ratio produces a higher EGT and allows the pipe to produce more over-rev?
Is the corresponding loss below 11,800 also a function of pipe temperature or a victim of less efficient combustion?

[husaberg]

I can only speak for the Aprilia RSA: its big end bearing is bulletproof. On the test bench it lasts a full season. But on the track it all depends on the rider.
Flashback: when leaded fuel got banned in GP racing, the Aprilias went from a 19.5:1 compression ratio to 14:1. Works riders Harada and Rossi had no problems (on the contrary: the engines became much more flexible) but Capirossi suffered one big end failure after another.
The datalogger revealed the reason: when signor Capirossi came upon a slow corner, he shifted down three times and then grabbed the front brake. In that order. Engine braking they seem to call it. Engine breaking more like...
With the previous 19.5 compression ratio engine braking was such that the revs went up to 15,000 for a moment. But with the 'unleaded' compression ratio Capirossi's engine revved to 17,500. Bye bye big end .

Wobbly has a point here. limiting the ignition retard yields cooler exhaust gas which may even result in your whole engine running cooler.
And in case you fear a loss of overrev, consider lowering the compression ratio. Helps against deto too...
(and in case you fear a loss of power, you could be pleasantly surprised)

Move to unleaded might benefit the thermally challenged as well as a drop in comp

Depends largely on the end use and the bmep capability of the engine.
The defining factor is the dynamic compression - this is created by the addition of the static com and that created by the combination of trapping efficiency and the delivery ratio.
The higher the trapping and delivery efficiencies are then the max static com that can be tolerated short of detonation ,is reduced.
But a good example is a conversion I did to a brand new TM KZ10 kart engine.
This was designed to run in open class and has a 60mm piston giving 152cc.
The regulations only allow unleaded pump gas, and initially it was run with the standard straight line ignition.
I played with a few combinations of com and static advance with a det sensor bolted to a head stud.
This engine would have state of the art trapping and delivery numbers , especially with a VF3 and 36mm carb in place of the 30mm regulated unit.
Thus a fairly low com was needed to get the right combination of peak power and overev capability when pushing up against the over advance created by the non retarding ignition.
It ended up with 13.2:1 full stroke and this setup was right back at the original numbers of 15* advance and 1180*F - the lower egt caused by the excessive advance.
Any lower on the com and the peak dropped ( 58Hp crank @ 12800 ) but any higher and the peak remained constant but it detoed in the overev at 14400 +.
This deto could be suppressed by going richer, but then the power suffered everywhere.
With a proper ignition I would guess at 13.8 :1 and an egt up at 1280 as unleaded burns alot faster than AvGas and added to the extra retard able to be dialled in with a digital.

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

[wobbly]

If you look at the numbers that matter then the performance increase gets put into perspective.
At 9000 its 3 hp down in 8 = a 37.5% loss.
At 12200 it has gained 0.5 in 14 = a 3% increase over baseline - for sure worth having.
So overall the mods are really a colossal failure, but when the rev band really is simply moved to the right by 700 rpm then this will probably
allow a couple of teeth to be added to the rear sprocket and the engine will then accelerate faster to the same terminal speed.

[Frits Overmars]

What is at work here? The lower compression ratio produces a higher EGT and allows the pipe to produce more over-rev? Is the corresponding loss below 11,800 also a function of pipe temperature or a victim of less efficient combustion?

The higher EGT not only yields more over-rev; it works over the entire power curve, so the pipe is now 'too short' below 11800 rpm.
As a result, below 11800 rpm the cylinder filling will suffer compared to that of the original high-compression engine, combustion will be slower, that will raise the EGT even more, and this 'chain reaction' causes the substantial power loss below 11800 rpm of the low-comp engine.
In addition, the high-comp engine has a bigger expansion ratio, hence less-energetic exhaust gas, that will do less harm at the torque hole at 2/3 of max.torque rpm.
In short: the low-comp engine has more potential because it feeds its exhaust pipe with more-energetic exhaust gas, but it is also more pipe-dependent.
It may also take more advantage of a programmable ignition, but I'm not sure if this is allowed in the Simson-class that Lucas is riding in. Lucas??

... when the rev band really is simply moved to the right by 700 rpm then this will probably allow a couple of teeth to be added to the rear sprocket and the engine will then accelerate faster to the same terminal speed.

Right, Wob. You could say that if we move the low-comp power curve to the left (or the high-comp curve to the right), the low-comp curve will fit over the high-comp curve everywhere. But rather then moving the whole curve by 700 rpm, I would propose to move each rpm point of the curve by 5,9% (high-comp max.power is delivered at 11550 rpm; low-comp max.power is delivered at 12235 rpm; 12235 / 11550 = 1,059).
With such a percentage-operation the curve will not simply be moved, but it will be stretched or compressed; the zero rpm-point will always remain zero rpm, as it should.

As it happens, I just received a mail from Neels van Niekerk, better known as Vannik, the brain behind EngMod2T. Neels has been playing with my power range concept and he also appears to visit the Kiwibiker forum. It was a pleasant surprise that he sent me both Lucas' power sheet and the corresponding power range graph.
The power range concept compares power curves on the basis of the acceleration that they can provide, and as Wobbly already predicted, the low-comp engine (the red power range curve below) is a winner, when geared appropriately.

[TZ350]

Finally getting some place with the EFI after strapping a small laptop onto the tank and riding the bike around looking for the bad spots in the map. I can now wind it out, throttle off and have it come back onto the throttle again. Its now ride-able enough to make it worth taking to a practice day for further refinement.



Dyno runs recorded at 100-90-80-70-60-50-40 and 30% throttle.

I have made more power in the past but the point of these dyno runs is that it is running reasonably well at different throttle openings and it is also something of a guide for refining the Alpha-N map some more.



Its a two stage injector system with three injectors, the middle 60 g/min unit is for starting, slow running and over run after shutting off. A pair of 80 g/min units provide fuel as the engine comes on the pipe then the middle injector chimes in again so all three are firing as the rev's get around 10,000 rpm.

I checked the data logger and the middle injector is chiming back in at 9,500 rpm on WOT so I have achieved one of may aims, squirting raw fuel at the underside of the piston crown to cool it when the engine is making real power, I am very happy with that.




My Ecotrons 2T two stroke Alpha-N map for the 125 is no where near 100% yet, plenty to refine but at last it is ride-able.


This is the first time I have felt truly optimistic and I am now looking forward to riding it in an actual race.

Ecotrons EFI kits .... http://www.ecotrons.com/products/2_s...injection_kit/

The biggest issue was selecting the right sized injectors, I had chosen ones that were to big, to big and there is not enough range of tuning adjustment and it took a while to work my way down to quite small injectors.

[TZ350]

As soon as I have been able to test the Suzuki GP125 EFI Beast in a real race then I can finish the new lighter Mini Beast. Which I hope will be a lighter, better handling version with the Honda MC18 chassis and an RGV cylinder on the GP engine with a 118mm diameter Kawasaki KE175 RV and a 34mm inlet. If the air cooled H2O cylinder idea works out then the Mk2 version is going to use an NSR cylinder on the GP engine with a 54x54 bore stroke conversion and a 122mm RV with a 38mm inlet inside the plenum.

[koba]

I love this shit.

Sorry, as you were...

[seattle smitty]

Ditto that!! Very cool projects, TeeZee!!

Add any more of those big copper heat-sinks, and the whole bike is going to take wing and fly . . . after which what will you do for traction?!!

[fatbastd]

There doesn't appear to be much front suspension travel..

[Lucas M]

Thank you guys for your response and sorry for answering late. At the weekend, there was the first race this year for me. The engine works great. I had a lot of fun during the race.

The message of the diagram posted by Frits was already in my head. I´m able to switch gear later, and because of this, the next gear starts with the same hp, but at higher rpm. For the first look, the new power diagram don´t seem to be like a benefit. While driving, I recognized it is a benefit. Thank you for your confirmation Frits and Neels.

Variable ignition is allowed, but it´s really expensive. I know that this would be a big improvement for the engine.

Frits, joining the German forum don´t seem to be easy. Someone have to do a suggestion with a new member and after that, there is an election, so I don´t see a way to get in there.

[Muciek]

Thank you guys for your response and sorry for answering late. At the weekend, there was the first race this year for me. The engine works great. I had a lot of fun during the race.

The message of the diagram posted by Frits was already in my head. I´m able to switch gear later, and because of this, the next gear starts with the same hp, but at higher rpm. For the first look, the new power diagram don´t seem to be like a benefit. While driving, I recognized it is a benefit. Thank you for your confirmation Frits and Neels.

Variable ignition is allowed, but it´s really expensive. I know that this would be a big improvement for the engine.

Frits, joining the German forum don´t seem to be easy. Someone have to do a suggestion with a new member and after that, there is an election, so I don´t see a way to get in there.

Check few pages back there was discussion about "simple" retarding unit for CDI (for pvl one and regular CDI). You can do some variations with it just need to have a strobe lamp for setting ignition. Using NE555 and some relay You could build a poor man 2 map ignition.(Switching by hand or by frequency).

[FastFred]

Hi Lucas, take a look at Ignitec ignitions, this is the model that Team ESE use on their singles:-

181 Euro for the CDI box then another 30-40 Euro for wiring harnes and CDI Coil etc,

http://www.ignitech.cz/en/vyrobky/dc...cdip2_race.htm

[Yow Ling]

Hi Lucas, take a look at Ignitec ignitions, this is the model that Team ESE use on their singles:-

181 Euro for the CDI box then another 30-40 Euro for wiring harnes and CDI Coil etc,

http://www.ignitech.cz/en/vyrobky/dc...cdip2_race.htm

CDI-P would work fine in Lucas's bike , I have one on my bucket, unless you have fuel solenoid, TPS, and powervalve you wont need cdip2 race and save 80 Euros as no special loom required and only 145 euro for the CDI