ESE's works engine tuner

[husaberg]

Much better to run a drum type throttle. You need a TPS and an in cable type liner type won't work well. Best it to have the TPS connected direct to the throttle shaft. Butterflies are not good in a twostroke inlet.

Yes you mentioned when we talked about the trouble you had with the splitter cable TPS (probably of a Suzuki RGV i guess?
I wonder if as well as the cable hang up issues the output signal was to course because it was designed to run the solenoids and maybe a ignition function only.
I amended my pic to one better match TZ's inlet port and on talks with people re the butterfly vs slide throttle body people often say the throttle response is more acceptable i guess due abrupt nature of the shape change i proposed .
So i have amended the shape slightly as well.



I think a proper linear potentiometer would offer finer control (eg like suspension telemetry uses or the fader from an old volume control to contrast etc Remember those
from memory there is even simple circuits available to condition their output to gain the desired outputs to throttle travel.


But what side up would the cut out go? wonder?

A flatter more wedge shape should be ultra short.
As it needs no area to blend the port weith the intake as well and help to clear the blocking effects of the crank wheels on The gp125.


Assuming the rotary valve GP125 engine is to be freed from the shackles of a carb.

Your ball throttle is super neat but well beyond us mere mortals
I absolutely love the variable rotary valve slider you did.
I see that as a far simpler solution than either the ball valve or my half arsed Photoshop effort i have done, if combined directly with a potentiometer.

[Forgi]

The problem here is that both examples you have given i would never work with.
Any 70 cc RACING engine at 10,000 rpm isnt even into the powerband, let alone pushing the limits of power with those timings.
All the work I have done is with full noise designs that are pushing the limits of what can be achieved in every area I can modify.
Trying to use my guide of making the header equal to the total Ex effective area, and making the duct nozzle = 75%, in an engine that wont make any power anyway, is
missing the point entirely.

Ok Wobbly, I can understand, you alright! I think basically we are talking about the same thing, but from different point of view.

I want to make clear that my examples of course are not about the max capacity as I'm talking about only 10k rmp. At 12-13K rmp a simple port won't generate a convenient blowdown STA even if we increase the exhaust port's angle up to 200 degrees.
Of course there is a huge and notable connection between the two things, but it would be hard for me to explain it in english.

Anyway, I'm gonna test it and if you are interested I'd share the results. Thank you for the conversation!

[wobbly]

The thing that overrides all of the thoughts on this connection between the duct vol/exit area - and blowdown capability,is that we are talking about cases where
we have huge ( relatively ) blowdown STA.
This implies that the engine is designed for extremely high power capability.
In these cases the Exhaust effective area and thus STA becomes pretty much irrelevant.
To the point that its a proven case we only need around 75% of this effective total exhaust area at the flange to achieve these high power levels.
As I have noted before, we can use the 75% guide, or simply calculate the main port area , and construct the duct to equal this - basically ignoring the big Aux ports completely.
All of these ideas have been tested on very high output race engines, now if you want to extend the thought pattern, to adapt the small duct to low power applications, then thats
completely fine - but I have no idea of the benefits, if any.

[Yow Ling]

I wonder if as well as the cable hang up issues the output signal was to course because it was designed to run the solenoids and maybe a ignition function only.

Not really convinced over the Coarse or Fine outputs from a TPS, if it is a potentiometer and you put a potential of 12v on the top , earth at the bottom, then assuming it is a carbon or ceramic track you will get an infinite range of 0 to 12v off the wiper . if it is wirewound with say 100 turns then you will get 100 steps about 1% still not exactly coarse. if it was a switch then you could say it was coarse, even if it had multiple taps.

[Flettner]

My TPS, although in cable, was a rotating device ( in fact the very same unit I'm using now ). The first cable went round a rotating quadrant, then a second cable off to the slide throttle ( a lake injector copy ). I had times when the slide would " hook up slightly " but the TPS not. Leeeean off idle but only sometimes untill I caught it in the act one day!! So that was the end of that, no more cable between these two units. I not telling anyone to do as I have done, just saying this is what happened to me.

[TZ350]

Kel gave me a hand tonight to try a resistor plug

Wob had suggested that the high RPM deto could be electrical noise from the old non resistor plug upsetting the Ignitec.

Kel warmed the Beast up and pulled a few runs until we were seeing high rpm deto and backfiring out of the carb at about 13k rpm.



Pulled the old non resistor plug and it looks rich if anything.



I made up a spacer for a 3/4 inch BR10EG resistor plug along the lines suggested by Wob.

There was no real difference, we still had high rpm deto and running on.

We tried advancing the ignition in the over rev area too but no change.

So the answer is not there either.



The curves for the two plugs look about the same. Powers down, over rich is my guess.

Kel points out that when it was running on and he had his thumb on the kill switch he could open and close the throttle, and the induction sound changed but the motor did not respond even though it was auto igniting.

As the motor was auto igniting and running on, when he let the kill switch go, he could open and close the throttle and the motor would respond.

So:-

Ignition off, running on by auto ignition and open/close the throttle = non change.

Ignition on, and running on by auto ignition and open/close the throttle = change.

Whats that about?

[husaberg]

Not really convinced over the Coarse or Fine outputs from a TPS, if it is a potentiometer and you put a potential of 12v on the top , earth at the bottom, then assuming it is a carbon or ceramic track you will get an infinite range of 0 to 12v off the wiper . if it is wirewound with say 100 turns then you will get 100 steps about 1% still not exactly coarse. if it was a switch then you could say it was coarse, even if it had multiple taps.

Not surprised Mike and Neil i didn't really put across clearly what i meant.
What i am suggesting if you have a TPS remote mounted driven by a cable with a slide driven from a cable at the other end i don't believe necessarily 50% of the tps is always going to accurately reflect 50% throttle throw in a TPS that is reading in a rotating arc a likely not designed to truly reflect actual % of throttle position perimeters. What i are suggesting is a likely more accurate way of measuring throttle position is to measure the throttle position at the source and in the direction of the actual motion.
Lastly i don't agree with the 100 steps. But at the end of the day all the Stuff i deal is above 66KV.
The filtering comment was from a PDF(2.1MB) i can't post but was basically a Fly by wire system piggy pack so the throttle response could be tailored based on a PWM circuit.
But yeah that's extreme Overkill esp considering my bike is in two separate Islands and the cylinder is uncast and untested and unfinished.

My TPS, although in cable, was a rotating device ( in fact the very same unit I'm using now ). The first cable went round a rotating quadrant, then a second cable off to the slide throttle ( a lake injector copy ). I had times when the slide would " hook up slightly " but the TPS not. Leeeean off idle but only sometimes untill I caught it in the act one day!! So that was the end of that, no more cable between these two units. I not telling anyone to do as I have done, just saying this is what happened to me.

What he said Mike
Whats the trade deal on one of those custom variable disk housings maybe a with a say of PV gubin thrown and cylinder dome thrown as well.

[Frits Overmars]

Seeing spark plugs and a fork spanner in the same picture makes me shiver. Ring spanners and socket spanners are OK but a fork spanner acts on only two corners of the spark plug's hexagon. That may push the plug body out of round, resulting in leakage inside the plug.

[TZ350]

Seeing spark plugs and a fork spanner in the same picture makes me shiver.

Eeeek yes, no, the fork (open end) spanner was just to prop up the plugs so the plug numbers could be seen in the picture. You can just see part of a proper plug socket and ratchet in one of the other pictures.

[Yow Ling]

Not surprised Mike and Neil i didn't really put across clearly what i meant.
What i am suggesting if you have a TPS remote mounted driven by a cable with a slide driven from a cable at the other end i don't believe necessarily 50% of the tps is always going to accurately reflect 50% throttle throw in a TPS that is reading in a rotating arc a likely not designed to truly reflect actual % of throttle position perimeters. What i are suggesting is a likely more accurate way of measuring throttle position is to measure the throttle position at the source and in the direction of the actual motion.
Lastly i don't agree with the 100 steps. But at the end of the day all the Stuff i deal is above 66KV.
The filtering comment was from a PDF(2.1MB) i can't post but was basically a Fly by wire system piggy pack so the throttle response could be tailored based on a PWM circuit.
But yeah that's extreme Overkill esp considering my bike is in two separate Islands and the cylinder is uncast and untested and unfinished.


What he said Mike
Whats the trade deal on one of those custom variable disk housings maybe a with a say of PV gubin thrown and cylinder dome thrown as well.

OK maybe I follow now, are you concerned the position of pot isnt zero when throttle closed and isnt 100% when fully open. If you are using an ignitech you dont need the full sweep of the pot just a start and end voltage , it sorts out the rest without extra circuitry. I now see what you mean about the 100 steps, in your world thats about 660v per step !!!

[Ocean1]

OK maybe I follow now, are you concerned the position of pot isnt zero when throttle closed and isnt 100% when fully open. If you are using an ignitech you dont need the full sweep of the pot just a start and end voltage , it sorts out the rest without extra circuitry. I now see what you mean about the 100 steps, in your world thats about 660v per step !!!

Also, depending on the mechanical relationship between the throttle shaft and the pot it's quite possible to have zero=zero and 100%=100% but increments inbetween out of step. Is unlikely if the pot's driven directly, (axially coupled) from the throttle spindle, eh?

[speedpro]

None of which matters as the TPS tables map a reading to a value. Who cares if the carb slide and the TPS dont have a perfect relationship. You could have say 30 values mapped over the first 50% of throttle movement and 70 values over the remaining 50%. As long as it never varies it doesn't matter. You may lose some resolution in one area and gain it in another. Unless you lose a LOT of resolution it won't matter.

[Flettner]

The link is the same, you tell the computer idle ( throttle shut ) and then you tell it full throttle, it works out the steps for you. You tell the computer how many steps you want ( up to ten I think ). If you have a problem area you can ( fine fuel control needed like just off idle ) you can zoom in to much higher resolution in the problem area ( fine tune it). This overlay can be done in four separate areas. The problem is when, like with my cable system, the throttle and TPS don't move the same each time, they must work together and the same each time. Solid mounting the TPS to the throttle shaft does achive this. Butterflies are for the garden.
I may have a small order for half ball throttle valves ??

[husaberg]

OK maybe I follow now, are you concerned the position of pot isnt zero when throttle closed and isnt 100% when fully open. If you are using an ignitech you dont need the full sweep of the pot just a start and end voltage , it sorts out the rest without extra circuitry. I now see what you mean about the 100 steps, in your world thats about 660v per step !!!

remember its was for Fuel Injection though,rather than for the ignitech
Yes i am likely over stating as now i think bout it more i doubt half throttle is likely to be half movement slide on a carb anyway.
maybe Neil can add how forgiving the Fuel injection is? i certainly can't, but i are guessing the map for a small 1 cylinder 2 stroke needs to be a hell of a lot more refined than a large capacity 4 cylinder four stroke.

i only threw out the squished shape (to match Robs Port)Slide carb (not butterfly)

with a linear TPS as it seems the simplest shortest solution remember.
As i said i liked the throttle slide cum Variable timing better as it even simpler and just as if not more narrow,



Anyway it seems i just brought a NSR50 or MTX/MTX50 motor for $1.
F5 maybe? not that i have ever seen one.
I must admit i never really had a close look at the pic and just assumed it was a CR80.The tacho drive should have been a bit of a giveaway.
Judging by the water pump grass adornments and the open intake i bet it's real mint inside with our maritime climate and all.

[teriks]

Kel points out that when it was running on and he had his thumb on the kill switch he could open and close the throttle, and the induction sound changed but the motor did not respond even though it was auto igniting.

As the motor was auto igniting and running on, when he let the kill switch go, he could open and close the throttle and the motor would respond.

So:-

Ignition off, running on by auto ignition and open/close the throttle = non change.

Ignition on, and running on by auto ignition and open/close the throttle = change.

Whats that about?

This auto ignition was was in gear, clutch out, on the roller at high RPM?
If so, perhaps the auto ignition occurs very late, producing little to no power?

Can you do a test with an all aluminium head?

The cu sheet could act as an catalyst and be part of the problem, especially if you have a hot-spot on it somewhere.

EDIT: I know that copper is a catalyst to at least acetone and methanol, so it's not too far fetched to think that it can lower the auto ignition temperature of gasoline too.