ESE's works engine tuner

[TZ350]

.

My new carb, not exactly the one Wobbly suggested ... but something to look at and learn how it is supposed to be used.



Throttle position sensor and electric power jet.......... how are these used?

[kel]

My new carb,

KX125? I love ebay

[kel]

Come to think of it didnt Kawasaki dump this carb after only a couple of years and go to the no frilles Mikuni TMX

[TZ350]

KX125? I love ebay

Me too .

...... didnt Kawasaki dump this carb after only a couple of years .....

............... what ............ no, your just trying to upsetme ......

[TZ350]

My early efforts at a retarding ignition......

Well that was fun, an afternoon on the dyno with Gavin from Henderson motorcycles dialing in the RM retarding ignition. The idea was to have the ignition over advanced in the lower revs to pickup some extra torque and then retard back for max power as the revs went up.

What Frits has to say about how retarding ignitions work.

"" In a 125 cc race engine the spark-plug sparks at about 14° BTDC @ 13000 rpm. Then combustion starts really slow: after the spark another 10° go by before you can detect the first signs of combustion. Then combustion continues for a little over 40° (this is at full throttle; with less cylinder filling, combustion is a lot slower).

Is it useful to slow down combustion on some operating phases? Yes and no. I will try to explain this in a little physics lesson.
No matter which way the piston is moving, as long as there is combustion, the pressure in the cylinder keeps rising. Only after combustion is finished the expansion of the burnt gas can begin.
Slow combustion means that the piston is already well on its way down before expansion can begin; it means less expansion for the burnt gas in the cylinder before the exhaust ports open.
Less expansion means less cooling down of the gas in the cylinder: it is still hotter when it enters the expansion chamber. In hotter gas the speed of sound is higher and that means a higher resonance frequency for the cylinder-pipe system, so it works better at high rpms.

But how do you slow the combustion speed down? Less squish? Mixture too rich? You do not want to do that...
Fortunately there is a simpler solution. We do not slow combustion down; we just start it later: we retard the ignition timing. As far as the exhaust gas temperature in the expansion chamber is concerned, the effect is the same: the engine runs better at high revs.
That is the reason for programmable ignition systems.
Below the power band the ignition advance can be more than 30° so that there is a whole lot of expansion; the burnt gas contains hardly any energy when it enters the exhaust pipe, so the exhaust pulses that arrive at the wrong moments at low rpm, are weak and will not disturb the scavenging too much.
At the rpm of maximum torque the ignition advance is about 14° (careful, a litte too much advance here and you get detonation), and at maximum revs the advance can be 10° or less (Honda even went to 3° after TDC"

A programmable ignition is the way to go.........

I got the job of setting up NedKellys IgniTech programmable Ignition.

With the initial advance setup more or less where you want it, you are ready to rock and roll on the dyno optimizing the ignition curve.

The IgniTech software is very clever as changes to the ignition curve can be made on the fly and the Ignition itself re-programed while the engine is still running............

There are more pictures and a vido on the original post.

Some Pictures from Buckets post on setting up a programmable ignition from scratch.

[TZ350]

Frits's ideas on radiusing the edge of the barrel where the transfers are.

""noticed that the inner radius of your transfer ducts ends in a sharp edge at the cylinder bore.
Most cylinders are like that. But not the Aprilia RSA...
Below I have tried to show this, using a picture of my FOS cylinder (which has radii identical to the RSA).
There is some good horsepower in that modification"" Frits.

[TZ350]

.

I am out serching for a piston and rod kit for my new project.

Here is TKR's home site, http://www.tkrj.co.jp/product/index.html

There is a 13mb PDF download catalog with dimensions.

[TZ350]

Can't wait to see what Wob is cooking up.



Desperatly keen to get started on my Wobbly engine.



Who said money and a smile can't buy you an Aprilia RSA

[TZ350]

How many hp is that on a 28mm carb? I make it around ....... 50!!!!!

[TZ350]

Buddfab Motorcycle Streamliner –Worlds Fastest Small Displacement Motorcycle

50cc, 100cc, and 125cc World Records (pending FIM ratification)

This is how they ran:
50cc Blown Fuel 144.891mph
100cc Gas Normally Aspirated 155.110mph
125cc Fuel Normally Aspirated 186.649mph (over 300kph)

Eric’s cockpit video of the 125cc 187mph down run:
http://www.youtube.com/watch?v=Vz_r_3yqqR4

John’s cockpit video from last year of a 50cc 141mph return run:
http://www.youtube.com/watch?v=mYINrhTNiyM

2009 BUB Report:
http://www.geocities.com/buddfab/buddfab3

Scraped from the net........ interesting speeds from 50's and 125's and shows what aerodynamics can do for you.

[speedpro]

How many hp is that on a 28mm carb? I make it around ....... 50!!!!!

I was chatting to JC yesterday and it sounds like the carb restriction for aircooled 125s is close to being a thing of the past. I mentioned to him that it generally wasn't considered to be a handicap now but I didn't get the impression he was going to stop the change. He sees the restriction to air-cooling as being the limiting factor which I think TZ would agree with.

He had some interesting thoughts on the "fast" FXR150s and cited figures from other quick 4 strokes.

[speedpro]

How many hp is that on a 28mm carb? I make it around ....... 50!!!!!

I was chatting to JC yesterday and it sounds like the carb restriction for aircooled 125s is close to being a thing of the past. I mentioned to him that it generally wasn't considered to be a handicap now but I didn't get the impression he was going to stop the change. He sees the restriction to air-cooling as being the limiting factor which I think TZ would agree with.

He had some interesting thoughts on the "fast" FXR150s and cited figures from other quick 4 strokes.

[TZ350]

I was chatting to JC yesterday and it sounds like the carb restriction for aircooled 125s is close to being a thing of the past. I mentioned to him that it generally wasn't considered to be a handicap now but I didn't get the impression he was going to stop the change.

I think it was Wobbly and others too, have pointed out that fast kart engines make over 30hp with 24mm carbs.

He sees the restriction to air-cooling as being the limiting factor which I think TZ would agree with.

Traditionaly aircooled F4 125's 2Ss have always lagged behind the 100cc water cooleds and I havent been able to do any better either, its a water cooled 100 for us next year.

[ajturbo]

Remember going to watch at Mt Welly many moons ago, at the height of the RG50 era. F5 bikes outnumbered F4 by two or three to one. Wonder where they all went, given that there are about five regular F5 runners in Auckland now.

still got mine......

[ajturbo]

I was chatting to JC yesterday and it sounds like the carb restriction for aircooled 125s is close to being a thing of the past. I mentioned to him that it generally wasn't considered to be a handicap now but I didn't get the impression he was going to stop the change. He sees the restriction to air-cooling as being the limiting factor which I think TZ would agree with.

FUCK YEAH..!!!

GT125's rule.... (if i could ride it that is..lol)