ESE's works engine tuner

[F5 Dave]

I'm confused so who is going to play Anthony Hopkins in the movie about Rob racing old Suzukis in a few years time? And who will be Clarice Starling? perhaps SS90 will be available if Jodie Foster isn't. I mean we might as well turn this into a fusion adversity over Thriller Horror movie.

[richban]

The thing that pisses me off is that SS90's are cool. I know a guy in germany the collects them and lots of other global vespa people. They are really cool people doing amazing things with the old airplane starter motors that they are. SS90 is giving them a bad name. TZ is doing an amazing thing here. Its like open source for 2 stroke tuners. If i didn't have connections on the dark side of the force I would be implementing the gold that has been laid down in this thread across the years? Not sure when it started now. Fuck off 90 or have some respect. Cock.

[wobbly]

My votes for playing Tee Zee are Woody Harrelson, only just ugly enough.
But the shoe in for SS90 has to be Sharon from Kath and Kim - perfect likeness - always seeking attention and obviously just fukin dumb - from everything she says..

[Farmaken]

Bang on wobbly, go hard TZ.

[Yow Ling]

Could this possibly be SS90 on his high powered bucket buster?

I think it is !

[Bert]

........
TeeZee, forget the twats saying detune the GP125 - forget your thoughts on doing anything else at all - make it reliable.
At 30 Hp its fast enough to win anything.
The power being made didnt affect the piston falling into the too wide EX, the power being made didnt overadvance the midrange timing, the power didnt make the ring pin fall out - etc etc

Quite right, however, using the same logic, ######### to achieve this power has overstepped the boundaries of mechanical reliability.

Would reducing the width of the exhaust port (##########) not reduce the the BDTA, and therefore, infact, be "detuning" the engine?

Dropping 2 P.S and designing an exhaust and cylinder head for what can only be described as massive gains, and designing an exhaust to suit (bearing in mind they only have 5 Ratios to transmit this through)
########
Either that, or some sort of solution to the too wide exhaust port has to be found.... Maybe an exhaust bridge of some sort....?

Devils advocate... (not forgetting my only red rep since 2005 came from SS90)..here Page145!!
I think we might be all "trigger fingering" a little fast here towards SS90 (all be it removing the history ###). He does have a couple of valid points which has been discussed here over the past 12-18 months. Suzuki never designed the GP125 for these types of performance figures; TZ (and the entire team ESE) has done some amazing work in public space proving that is it possible to do to the poor old thing.

SS90 has posed a couple of valid questions here (useful mainly for people thinking of following the ESE lead in building a GP125 racer).
30 Hp is achievable (following the great resources on this thread) it may actually be pushing past the mechanical boundaries of the actual engine design; would 27-28 be the same??
and is it's overall performance ultimately limited by the 5 speed box?? (would you actually notice 2-3 peak HP??)
Could a new sleeve with a bridged exhaust port offer a better overall solution to reliability?? (I ask this as my 100 is on the limit as well & we have discussed the merits of this a while back)...
what actually caused the ring pin to fall out? (who actually knows) but Yamaha TZs did have issues here in the past; ironic given that they also had large single exhaust ports (is it a ring hammering effect caused by the ring passing in and out of the wide exhaust port? resulting in pin issues) I have some vague recollection of someone (s) telling me that I was in for similar issues....

Kel; bad luck mate heal fast; its not the best fun being the crash tester...

[Frits Overmars]

To give you some idea of what I'm messing with, something completely off topic. -except for being two-stroke and somewhat bucket, as in old engine, well, and some tape and tie wire.
Attachment 268553
.. or maybe I just like the beautiful blue color and need to share it somehow

Gee, that's the old MB40 engine with rear inlet valve and clumsy cylinder fixation - three bolts going down from the cylinder into the crankcase and two going up from the crankcase into the cylinder which means you have to remove the engine from the plane each time you want to pull the cylinder down. It was a learning curve for us .
I can't tell from your picture but chances are it even has a steel crankcase.
Here's some noise trom the little miracle: http://www.youtube.com/watch?v=5aBCQGq5Al4

[andrew a]

Hi guys just poped onto this threed and saw Kels pics. Impresive. Sorry to hear about broken bones though. Hope it heals well.
Keep up the good work guys. I find it dificult to see where you get the time.

[bucketracer]

SS90 has posed a couple of valid questions ...

Re read the original SS posts, valid questions sure, genuine even, they could have been if they had been asked without the embellishments.

..... the bike in question just seems to be being tuned to a standstill …. People can jump up, Lay eggs, and wave pitch forks about all they like.

… one would have to wonder if someone is heading in the right direction... As you can produce an immense amount of torque from a two stroke, with-out any of the crap that thing has bolted on to it.

Better spreads of power are made everyday with far less of the gubbins this poor old whipped mule has.

So whats your take on the superfluous verbiage in his posts.

Maybe SS90's posts were genuine, so here they are answered by a genuine industry insider.

The Ex port isnt the problem here.
At 72% width it will live forever, and at 78.5 ATDC who says its too high, it will support near on 40 Crank Hp.
The STA numbers show the Blow will support near on 40 crank Hp as well, so the system is inherently a match, and if the ports and pipe are SOTA it WILL make 40 crank Hp - with plenty of powerband width.
Its all but been done already, without trick shit transfers or pipe..
What IS the issue is the inlet port and its tiny carb, this is where all the effort needs to be directed, and TeeZee has already done a heap.

The sidetracks of Ex port width and ignition anomalies is simply an artifact of TeeZee learning what not to do in public.

[husaberg]

Here's some more Helmholtz-encouragement:

Regarding induction systems: build a short induction tract and visit a test bench.
You can forget about calculations. The formulas you find in various books are all based on the Helmholtz resonator. It made me write a simple story, called:
Helmholtz blues
"A Helmholtz resonator consists of a volume connected to a duct". That is what Wikipedia tries to tell you.
But that is a Helmholtz resonator in its simplest form; one that you won't find anywhere in an engine.
What you do find in an engine is an intake tract with a variable cross-sectional area. This tract is from time to time connected to a variable volume (the crankcase) through a very variable window (the intake port / reed valve / rotary inlet).
The crankcase is connected to a number of transfer ducts with variable cross-sectional areas, which are from time to time connected to a very variable volume (the cylinder) through a number of very variable windows (the transfer ports).
The cylinder is from time to time, through a very variable window (the exhaust port), connected to an exhaust pipe with a very variable cross-sectional area who at the same time doubles as a volume. This pipe volume is constantly connected to a big volume (the outside world) through a tailpipe with a constant cross-sectional area and constant entry and exit windows (thank God, finally someting that's not variable).
We call this a compound Helmholtz resonator .
The various papers also tell us how to calculate the resonator's frequency:
" frequency = speed of sound / (2*pi)* Sqr ( cross-sectional area of the neck / ( volume of the resonator * effective neck length ) ) ".
O yes, the speed of sound... It is dependent on temperature, which is not really constant in the intake tract and the crankcase, rather variable in the transfer ducts and very variable in the cylinder and the exhaust pipe.
Now the above frequency formula is not exact; it is an approximation that is usable as long as the volume of 'the' tract is very small compared to the resonator's volume.
So when engines are concerned, that formula goes very far out the window.
Who said gas dynamics is simple dull?
PS:
It's a similar story with acoustics. That is a sub-branch of gas dynamics, simplified with a lot of assumptions that are acceptable as long as the sound pressure does not exceed a certain limit. The wave pressures in a two-stoke exhaust exceed that limit by a factor of thousand. Bye bye, acoustics...

I think i found the bit where i misquoted Frits from. Bloody couldn't find it last time.

Helmholtz frequency, my dear Watson. The smaller crank will give the pipe more crankcase volume to breathe from. This larger volume will also lower the resonance frequency of the inlet system, hence the drop at high rpm. It can be compensated with a shorter inlet tract, a bigger carb diameter and a later inlet closure. To put it real simple: if you have more volume, you need more time to fill it. But more time, i.e. later closure, has adverse effects at low revs. So my preference is a shorter tract (unless you go the 24/7-way and employ a reed for the low revs, and swing it out of the way at high revs).

[teriks]

Gee, that's the old MB40 engine with rear inlet valve and clumsy cylinder fixation - two bolts going down from the cylinder into the crankcase and two going up from the crankcase into the cylinder which means you have to remove the engine from the plane each time you want to oull the cylinder down. It was a learning curve for us.
I can't tell from your picture but chances are it even has a steel crankcase.
Here's some noise trom the little miracle: http://www.youtube.com/watch?v=5aBCQGq5Al4

Thats the one, steel crankcase from 1999, new cylinder though. My favorite cyl. from 1999 finally gave up in June, cracked around one of the head bolts. -Robust stuff :-)
I'm using the old stuff for fun, and to try a lot of stupid and a few not so terrible things on. The fun part is when i can keep up with the latest generation engines speed-wise

My rather long term plan is to build my own rear induction crankase for the long-stroke, the design is coming around ever so slowly...

[Bert]

Re read the original SS posts, valid questions sure, genuine even, they could have been if they had been asked without the embellishments.

So whats your take on the superfluous verbiage in his posts.

Maybe SS90's posts were genuine, so here they are answered by a genuine industry insider.

hence the #### not ..... in the quotes

My take; maybe too much time in the eastern block ?? banging his head against a wall dealing with scooter people???

the point I was making is that maybe there is scope in his points (he is also not alone in his comments about bridging the exhaust port to limit ring issues and gaining optimum durations and performance; I'm sure I recall Wobs being part of that as well ---I'll go look for it might be wrong).

[ief]

Could it be that the exhaust outlet does have something to do with it, not by being to large then but by being unsymmetrical?

[wobbly]

You guys arent getting it at all.
All the issues that the GP125 engine has had, have NOTHING to do with the power it makes.
It would have died at 22 Hp with the Ex port too wide.
It would have died at 17 Hp with the incorrect ignition timing
It would have died at 12 Hp when the ring pin fell out.
Need I go on.
Of course all this type of shit normally happens behind closed doors and gets chalked up to experience.
Its being done here in the open for everyone to learn from.

[FastFred]

We had hoped to spend the last race meeting tuning the handling but having the directive to enclose the carb inside a catch tank sprung on us at the last minute left us scrambling to get it running right again which is a bit much on a race day.

Chambers points out, it was a team decision and you had a week and a half ......