ESE's works engine tuner

[Grumph]

Old Trevor at 70 is of course taking a long time to recover from what would be a simple bruise to a younger man.
But he is running into trouble with the medical system as the crash has reinjured an old damaged vertebrae he got in practice for
the 350GP he won in Malaysia around 30 years ago.
Because they say ACC wont pay to "fix" it, they wont do anything - wankers.
Hasnt improved "Grumpys " demeanour any as his sponsored Arai is a mess as well.

Yeah, getting a new helmet is tough on the pension...the bugger was hard enough to race against in the 70's. Good on him for still riding - i'm a little younger but have enough health issues to pretty well rule out anything serious.
Once they (ACC) see you as being outside the workforce, you're fucked as far as getting anything fixed goes. Some of us were hoping Cashman would retire to NZ and he would be a way through the system - but that won't happen now.

[husaberg]

Armstrong Crankcase mirrored for the Aussie...................

[TZ350]

Page 920... there is a lot of information here, you will need to follow the link trail back to the original post to see the pictures and full text.

Frits, many many thanks for a great article ( and the previous 300 odd posts)

I have learned more in the last year reading posts from you, Wobbly and others than I have in the previous 50 years of 'playing' with two strokes.

I do not have much to offer to the discussion (apart from more questions!) but some may find this useful. Rather than use the site search which usually fails, use Google so to search this site use an ordinary search phrase and after it add

site:www.kiwibiker.co.nz

for example

Frits priceless site:www.kiwibiker.co.nz
or
Frits pisa site:www.kiwibiker.co.nz

the same will work for other sites with the appropriate site address

Mick

Thanks to Mick for his search tips, now its easy to find good stuff on this thread.

I have often wondered why no one has really gone into expansion chambers in a big way on this thread.....

They have you just wernt looking. In fact your first rants were about how Thomases cousin stole the worlds best pipe design from your mate the pipe genius and that was why all Asians could not be trusted ever again

Pipe Talk ... there is plenty here for those who want to design and build their own pipes. Starting from the beginning I have been collecting the posts that talk about pipes to collate and edit them for myself.

There is heaps of it and pages 620 630 640 650 660 670 680 690 700 710 720 730 740 750 760 770 780 have un edited collections of raw material. There is absolutly lots of good information here that even the professional pipe builder would learn something from.

You just have to make the effort to read through it and if your clever, take notes on the way.

Page 780 ... Setting up an IgniTec DC-CDI-Race-2 ignition

Page 820 ... more Ignitec http://www.ebay.com/itm/Knock-gauge-...-/181138934401 Rich these are the det sensor posts that I could find.

I have learned from Flettner, that a competition two stroke can be successfully fuel injected and that EFI can work very well on 2T's.

A lot of posts on this page are about Flettners EFI and video of dyno runs and field trials of the two EFI bikes.

EFI YZ250 in the Forrest

Page 800 ... Where I have got to with the EFI fuel injection system. You will have to click through to the original posts to see the attached pictures.

Page 890 ... a lot of posts about EFI and more about my EFI journey.

Page 900 ... Tonight's effort. The Beast is starting to snarl and it will pull away in top gear on the dyno from 3500rpm and WOT, try that with your carburetor. I am pretty excited about the Ecotrons fuel injection system as its starting to be very easy to work with.

I think this EFI business is going to work out OK.

This link leads to a thread started by Speedpro that is devoted to setting up the Ecotrons EFI system.

A guide to installing and using the Ecotrons electronic fuel injection ProCal tuning software based on the experiences of a complete newbee with no previous EFI experience.



The Ecotrons fuel injection system is my first experience with EFI. Sure, I had seen fuel injectors and mass air flow meters before and had some idea of how they worked but I was really a total newbee to EFI when it comes to installing one and setting it up.

Hopefully all this will be a help to anyone else trying to get their head around the ProCal file and directory structure.

Page 810 ... Bucket Racing Video from Chrisc's thread

and Pictures of the bikes http://www.kiwibiker.co.nz/forums/sh...-warning/page7 … Exhaust port dam.

Page 830 links ... Looking for the good stuff ... Plugging piston pins ... http://www.pit-lane.biz/t4140-2-stro...troke-wristpin And another approach taken by Wob, if any one is doing the piston pin thing this may be worth a try too. … Then Wobs thoughts on cylinder heads and plug to piston crown distance.

Page 850 link list ....

Page 860 ... Great little explanation of how a two stroke works. http://www.atvriders.com/articles/twostroke.html

Page 880 has a lot of foundry pictures ...

Page 900 ... To find the good stuff. follow the link to see how to view all the images on the thread and their associated posts.

Before calibrating an engine, it is first useful to have some concept of what you are trying to control.

"Fuelling Theory ... Lets start with the theory then. We are concerned with spark ignition gasoline engines here. I am only going to cover gasoline, since Diesel is for trucks and diggers, and alcohol is for drinking and drag racing." http://195.159.109.134/vemsuk/forum/...opic,97.0.html

Wobbly!

We have talked over how important the blowdown and it's size are, but what about the blowdown's intensity? If the aux exhaust ports are opening later as the main exhaust port, the peak of the pression is smaller, meanwhile the blowdown lasts longer. Of course the STA is always the same. Here is an example 'One Half'

In case of almost every race cylinder the aux exhaust ports are opening later, and this can be observed in systems with or whitout a power valve. In case of a T port the top edge radius is not 0, but pretty much bigger.

Is it important? Why don't we open the ports the widest possible? That way the ports could be positioned lower what would be optimal.

There are two factors in play with the tripple port setup.
You have drawn them correctly with 68% main port width, as this allows greater blowdown area to be gained via the aux ports.
Out at 72% that has proven to be approx the reliable max width, you loose some blowdown, and gain total area. ( not relevant at all ).
The problem is that even at 68% you cannot run a flat port roof with 8mm corner radi, as the ring life will be zero.

Secondly is that it has been proven in many dyno sessions that having all 3 ports open together looses power.
I can only explain this as a function of the fact that the effective duct length from the outer corners of the Aux is alot longer than that from the main port
mid point to the header.
Thus you get a smearing of the initial wave amplitude ( wider but lower intensity ) as it exits the cylinder into the duct during blowdown.
This reduces the effectiveness of the expansion phase, creating less depression around BDC, and less plugging efficiency as the piston closes the port.

It would appear that having a 68% main port opening first gives a good, high amplitude wave action in the pipe, then the Aux STA gets the blowdown pressure dropped as much as is possible prior to the Trans opening.

A few pages back was a drawing I did years ago of a T port with the outer edges higher than the mid point, thinking that this would ameliorate the duct length issue, but later
testing proved it didnt work well at all.
So by inferrence even lifting the Aux higher than the main wont fix this issue either in a 3 port.

[Gigglebutton]

Big thanks to Cully and Rob for your help with our bike. Could not have done it without you

[husaberg]

Pretty sure its KR3's
Plus allegedly a mid 90s YZR500 cylinder

[husaberg]

Other 90's yzr500 nYamaha bling

[RomeuPT]

You can find that graph here: http://www.kiwibiker.co.nz/forums/sh...post1130670008. But it was from a 50 cc engine; nothing to do with a 102-pipe.
In that graph the stainless and Ti pipes produced maximum power at about 13150 rpm and the mild steel pipe at about 12750 rpm; 3% less.
In this particular case the acceleration time on the dyno was quite short. A longer acceleration time would have promoted heat build-up in the pipes; especially in the mild steel pipe that suffers most from heat loss to the outside world, so the required length difference would probably be less than 3%.

less than 3% and 8%.. there is a big mismatch here

I have been making some SS pipes, always thinking if going right or wrong, but using about 5%

[TZ350]

I was out looking for a bit of info on frame design and handling and came across this gem about "the wobbles":-



Burst oscillations occurring at high speed, and under firm acceleration, can be suppressed with a mechanical steering compensator. Burst instabilities in the subject racing motorcycle are the result of interactions between the wobble and weave modes under firm-acceleration at high speed. Under accelerating conditions, the wobble-mode frequency (of the subject motorcycle) decreases, while the weave mode frequency increases so that destabilizing interactions can occur. The design analysis is based on a time-separation principle, which assumes that bursting occurs on time scales over which speed variations can be neglected. Even under braking and acceleration conditions linear time-invariant models corresponding to constant-speed operation can be utilized in the design process. The influences of braking and acceleration are modeled using d’Alembert-type inertial forces that are applied at the mass centers of each of the model’s constituent bodies. The resulting steering compensator is a simple mechanical network that comprises a conventional steering damper in series with a linear spring. In control theoretic terms, this network is a mechanical lag compensator. A robust control framework was used to optimize the compensator design because it is necessary to address the inevitable uncertainties in the motorcycle model, as well as the nonlinearities that influence the machine’s local behavior as the vehicle ranges over its operating envelope.

http://appliedmechanics.asmedigitalc...icleid=1662295

[TZ350]

A lot of the 2014 GP Videos are on Richbans thread.

There are so many GP threads why not make another one. Lets all try and put the footage and pics here. Here is the onboard from my bike. Some close and closer racing.

Lots of Bucket Racing video from Team GPR http://www.youtube.com/playlist?list...87n3mkhOHMXVSg

I started a Flickr just for you sods. Jump on in, the water's fine.

Congrats to everyone who finished, and to those who walked away with shiny things.
I had a freaking ball! and my puney muscles are still sore

TOKOROA GP PHOTOS HERE: http://www.flickr.com/photos/1202422...7642282552865/


_MG_3088 by sonscc, on Flickr

I'm totally happy for you all to save, share, print the photos on this thread and on my flickr. But please can you make a mention, provide a link etc where ever you use these. That'd be greatly appreciated. Enjoy!

[F5 Dave]

And despite the farty noises of the bikes in pic, the bike disappearing at the front is a 2stroke Derbi 80something.

[WilDun]

Didn't get to Tokoroa, would have liked to ..... maybe next year.

Good to see the fifties in action, as I said somewhere before, I have yet to see a 50cc race in NZ, looks like a lot of fun, but I guess a rider who is overweight wouldn't fare well in the acceleration stakes!
BTW, I used to ride an Italian 50cc ITOM sometime way back in the last century, (some hopefuls used to ride them at the first 50cc races at the IOM TT. - not much hope really!) - mine could manage 65 mph - guess that doesn't compare with the ones today, I also designed an expansion chamber by scaling it from a photo! - no "wobbly wisdom" in those days!

Thanks TZ 350 for taking the hard work from the browsing - makes things a lot easier.

Will.

[F5 Dave]

Didn't get to Tokoroa, would have liked to ..... maybe next year.

Good to see the fifties in action, as I said somewhere before, I have yet to see a 50cc race in NZ, looks like a lot of fun, but I guess a rider who is overweight wouldn't fare well in the acceleration stakes!
. . .

No I don't, that bit is kinda depressing. But even Slim David (in my 20s) was about 8kg heavier than some of the teenagers.

[mr bucketracer]

Didn't get to Tokoroa, would have liked to ..... maybe next year.

Good to see the fifties in action, as I said somewhere before, I have yet to see a 50cc race in NZ, looks like a lot of fun, but I guess a rider who is overweight wouldn't fare well in the acceleration stakes!

the f4 is also a killer with power to weight . would be nice if everyone had lead weights on there bikes to suit the heavy weights lol .

[TZ350]

the f4 is also a killer with power to weight . would be nice if everyone had lead weights on there bikes to suit the heavy weights lol .

I am all for it ... min 250kg Bike plus Rider in their kit and over 65's get a head start.....

[WilDun]

I am all for it ... min 250kg Bike plus Rider in their kit and over 65's get a head start.....

Now that's a good idea (not that i'll be able to benefit from it), especially the over 65 bit! that's what I say, a level playing field, also, I think the older guys should decide just where the lead weights should be added! - Why? well it keeps skullduggery to a minimum.
On the other hand, it wouldn't be much fun getting clouted by lumps of lead after someone had a high speed crash! Like the wild west, lead flying everywhere

Will.