ESE's works engine tuner

[husaberg]

Homeland Security's predecessors did have a puzzling interest in an early 70’s French Whitbread Round the World entry.

Eventually transpired it was ballasted with uranium.

Shame homeland security wasn't more interested in the French crew of the yacht Ouvea.

Oh well they do buy a lot of dairy exports and apples i guess

[TZ350]

I dont understand why you would spec a combustion chamber with a huge squish - 0.8mm when 0.65 is fine.
And no squish width, that gives no squish velocity at all at 18.7M/Sec - this is just throwing away a lot of power everywhere in the useable band.???.

True, but its 0.8 static I expect its less at 12,000 rpm, maybe 0.6.

And no squish width, that gives no squish velocity at all at 18.7M/Sec - this is just throwing away a lot of power everywhere in the useable band.???.

The std head has no squish at all, the squish you see is what appears after machining 4mm of the head, not much I know but it is all I have to work with without going to a lot of trouble welding up a head before machining it. Maybe next time.

As the Ex height has a big influence upon the trapped dynamic com, I use the trapped ratio.

Me too, and the head clearance volume changes quit a bit between 82* and 78.5* for the same com ratio.

For your air cooled 125 on AvGas a ratio of 7.4 will work reliably no matter where the port is. Here is the output with the Ex at 82*, double the squish velocity, and near on the same pumping pressure prediction.

That's very interesting.

[TZ350]

The Piranha pipe with the 3ex exhaust opening at 82* ATDC

This is where we got to tonight, not great, just like Wob said, and its cutting off just where it should realy be starting to get going.

But there is an up side, it means that I can raise the main exhaust port to 78.5 where Wob wants it and get a bit of seperation between it and the opening point of the secondries.



Sprung a few leaks in the chamber, working with 0.8mm is just a bit to hard, we need to practice a bit I think. ....

[dinamik2t]

But there is an up side, it means that I can raise the main exhaust port to 78.5 where Wob wants it and get a bit of seperation between it and the opening point of the secondries.

I am pretty sure you would lose even more power if you do that with the tripple EX setup.
I would suggest to rise the B,C TFR to 114~115; I believe this will help gain some high RPM power & overrev.

Next of course is the head, which you said it's done for now. To add to Wob's saying -if I can claim to do that-, you don't necessarilly have to use a short squish height. Make a head with a SAR =~45% and there you have your 30+ MSV, while keeping a safe squish height for rod/bearing movements @ high RPM.

Does the pipe has the 23mmD at baffle ending as in Wob's design or does it go directly to the 24.5mm RS stinger? If yes, count a few ponies gone missing from there too.

Finally, out of curiosity I run my 125cc sim with a dummy 24mm intake to see how it goes. It's 41.5hp, while +3 with the full 38 intake. My timings, if you feel like inspirating, are 81.5 for the main, 84.5 aux, 116/115/115 TFR. And "only" 13* ADV at its peak torque @ 11.8k.

[wobbly]

Squish depth in most 125 engines is safe at 0.65mm in that this means the piston will clip the head at around 14500,its a proven concept.
As you are going nowhere near that rpm there is no reason to run a wider clearance.
Getting good squish velocity induced turbulence in the end gases dictates a lesser need for ignition advance to generate the max combustion pressure.
Less advance = less negative work in compressing the mixture, its all free Hp.
What you have created is a chamber that would work well on a 125 ICC kart engine.
These have fixed advance and will detonate the end gases with close squish and big SARs, but when you have a digital ignition you have the huge advantage of
being able to accurately map the optimum advance to suit the flame speed across the chamber.
As I said, the faster the turbulence induced burn speed, the less timing is needed, for optimum performance.

And yes the pipe design i did was based around using a stinger nozzle.The pipe works very differently without a nozzle,and I would have done something completely different
if just a normal pipe stinger was going to be used.

[richban]

The Piranha pipe with the 3ex exhaust opening at 82* ATDC

This is where we got to tonight, not great, just like Wob said, and its cutting off just where it should realy be starting to get going.

But there is an up side, it means that I can raise the main exhaust port to 78.5 where Wob wants it and get a bit of seperation between it and the opening point of the secondries.



Sprung a few leaks in the chamber, working with 0.8mm is just a bit to hard, we need to practice a bit I think. ....

Looks Good Rob. If you can get rid of the dips at the start of the rev rang and the one at the top that looks like a very ridable weapon. Could the one at the top be an main air/jet main jet miss match. Not sure if the PWKs even have an air jet as such but I know that sometimes when you start pushing heaps of air through small carbs the main jet / air jet / bleed can become unbalanced. From what I have read and yet to put into practice. You want to run the main Air/Bleed/Jet the biggest that works. More air better atomization more clean burn more power. So I have been hoping anyway. Could be wrong but Just sharing some ideas that I am trying. Keep up the good work.

Re the bike setup. Something that should be cheap ish and eazy. I would be doing is a 415 chain conversion. No need to push the big chain and heavy sprockets. Should loose a heap of weight out of the rear. Then a new subframe and seat hight might put the rider in a more happy place as Husa has mentioned. The tank is massive for sure but when the seat comes up it won't seam such a beast.

[dinamik2t]

Wob, the highest-possible MSV rule (with min safe squish I mean) applies to all fuel types?
I remember reading a lot of discutions in a respectable 2t forum, concluding that needed MSV is relevant to fuel burn characteristics. and for example in normal unleaded (pump?) gas an MSV > ~30m/s would induce more heat to the engine than do good. Is this obsolete or just wrong ? (kind of the same though)
I am expressing it a little wrong or missing something - hopefully you too have Frits' special guessing ability

[TZ350]

... get one of these with the extra wire to ground.
When it sees deto it can ground an Ignitech input and retard the timing automatically.

You get flashing lights and engine protection all in one shot, and cheap as chips - made in Czech so it likes being connected to an Ignitech - same lingo.

Works perfectly - when you get it trimmed correctly it will tell you where to manually pull out timing, then it just operates as a failsafe.

http://www.ebay.com/itm/Knock-gauge-...ht_1582wt_1297

Ok mine turned up today.



And a couple of two wire sensors I picked up cheap from the local garage.

[2T Institute]

Wob, the highest-possible MSV rule (with min safe squish I mean) applies to all fuel types?
I remember reading a lot of discutions in a respectable 2t forum, concluding that needed MSV is relevant to fuel burn characteristics. and for example in normal unleaded (pump?) gas an MSV > ~30m/s would induce more heat to the engine than do good. Is this obsolete or just wrong ? (kind of the same though)
I am expressing it a little wrong or missing something - hopefully you too have Frits' special guessing ability

30m/s would be about the minimum you want.

[TZ350]

Looks Good Rob. If you can get rid of the dips at the start of the rev rang and the one at the top that looks like a very rideable weapon.

Rich, thanks for the encouragement, I have found that whenever I try something new I slip back for a bit before getting it sorted. Wobs pipe and engine layout is good for 30+, its my interpretation of it and workmanship that’s let it down, but I will get it sorted.

Could the one at the top be a main air/jet main jet miss match. I know that sometimes when you start pushing heaps of air through small carbs the main jet / air jet / bleed can become unbalanced. You want to run the main Air/Bleed/Jet the biggest that works. More air better atomisation more clean burn more power

Yes I am sure your right a “air/jet main jet miss match” is one of the issues.

Interestingly, it needs the power jet off below 8,000 rpm to get good carburation down low.

Re the bike setup. Something that should be cheap ish and easy. I would be doing is a 415 chain conversion. No need to push the big chain and heavy sprockets. Should loose a heap of weight out of the rear. Then a new subframe and seat hight might put the rider in a more happy place as Husa has mentioned. The tank is massive for sure but when the seat comes up it won't seam such a beast.

There are five GP engines/bikes in the Team ESE stable running 428 chain and sprockets, we already have a big investmint in sprockets and try to keep things interchangeable.

I am pretty sure the Bike was 50/50 with rider on board, maybe it was when the back was jacked up higher than it is now, or it was Chambers bike with the wire wheels we measured, the rear wire wheel on his bike is much lighter than an original FZR one.

I am definitely going to do something about the weight distribution now that I know what a good one looks like.

[richban]

Interestingly, it needs the power jet off below 8,000 rpm to get good carburation down low.

Hummm. Maybe the power jet jet is to big. Is it working to early? Main to big with power jet on maybe. Anyway look forward to seeing it out on track again.

[dinamik2t]

Good luck with the Deto sensing TZ. I like the little warning instrument!

Here's how I mounted my sensor. I drilled-tapped an old head bolt and screwed a stud.



My sensor has a PN 0-261-231-001, what's yours?
According to this http://www.phormula.co.uk/KnockCalculator.aspx , deto freq for 56mm bore should be 10.2kHz.
According to Bosch datasheets for PN -047 & -120, sensors are able to catch frequencies from 1 to 20 kHz.
I assume all Bosch sensors can sense knock within this range (?)

edit: As for the pick-up voltage, I think it won't be more than +-10V. I had a voltage test yesterday with a data acquisition device in real time! I spinned the crank by hand and recorder the voltage waveform from the pick-up in the PC. As RPM increase, amplitude (and freq of course) of the pulses increase - by hand-spinning it didn't exceed 3~3.5 VAC. Sure it was a lot of fun to watch!

[TZ350]

Hummm. Maybe the power jet jet is to big. Is it working to early? Main to big with power jet on maybe. Anyway look forward to seeing it out on track again.

Yes I enjoyed seeing you guys at Kaitoke, it was a brilliant weekend.

With no power jet at all the top falls off earlier with less over rev. I think it just comes on to early and I can use the Ignitec to fix that.

[TZ350]

Good luck with the Deto sensing TZ. I like the little warning instrument!

Here's how I mounted my sensor. I drilled-tapped an old head bolt and screwed a stud.

Thanks for the pics and tips. To be honest I am not sure what the the pickup has to do with it, at the moment I dont understand it at all.

I will look for any numbers on my pickups, could you please tell me more about how the whole thing goes together.

[richban]

I think it just comes on to early and I can use the Ignitec to fix that..

Fancy. Spoze you want it to start working a just past 3/4 throttle almost full.
I was just watching a video of Kaitoki. Good fun.