ESE's works engine tuner

[TZ350]

Then I started to tackle the Front mounts, F5Dave gave me the idea to use the triangles to create the front mount, and it was then that I realised I could use the original front isolating bushes of the donor chassis to mimic the original mounting scenario...
Attachment 283786

Attachment 283791

I like the front engine mount arrangement, looks much better than ours and its great to see another GP/RS125 out there.

I believe ESE boys made some respectable power (20rwhp or slightly more?) with the stock carb before switching to a 24mm.

Yes, low 20's is possible with the original carb.



We got most of our power by opening up the rear transfers and making the port windows as wide as possible. Low and wide transfer windows maximize the exhaust port blow down time area and therefore the power that's possible. In the end, the 24mm carb restriction proved to be not that much of a problem for 20+ hp.

[RomeuPT]

They are more or less acceptable. If you wish to measure all the way from 6000 to 15000 rpm, you will certainly have to pass through the torque dip at 2/3 of max.torqe rpm and this may give a mispresentation of the total acceleration time; most of this time will be spent getting through that dip.
Of course you will want to measure an 'entire' power curve occasionally, but in order to establish the flywheel dimensions for a given task it will be wiser to feed the flywheel program with the initial and final rpm values of the power band, and a matching acceleration time of maybe 5 to 6 seconds.

Your total transmission ratio looks like a crankshaft/clutch ratio. If that is also going to be the total ratio between crankshaft and flywheel, that will imply a gearbox ratio of 1 (could be top gear; no problem) and a final chain transmission, also with a ratio of one. And the latter could be a problem because you will probably not be able to fit a sprocket as large as the rear chain blade.

If I can't calculate a 250cc under 8000/7000 I would miss the whole botton end :/ and if I can't see 15000 I would miss a 50cc overrev. I have a lot of experience in C# programing, I will use the best of it to design the dyno software to be adjustable

Ok, using a NSR 125 stock as example, stock cluth, stock gearbox and transmission, 1850 mm tire piremeter, 350 mm flywheell, gear 4 (0.8258) I've got 0.6 ratio...

Thanks

[TZ350]

Final Results for Auckland 2.xls

Final AMCC F4-F5 Bucket and sidecar results for the season curtsey of Dave D.

[TZ350]

I expect that with a bit more time on the dyno we will get Kels Av Gas curve to extend out like the red line does.



Kel brought his air cooled KE125 engine around after running it at the track during Saturdays practice on Av Gas.



The inside of the piston crown is quite dark.

But the (cheapish) glue inside the piston sealing the exhaust bridge oiling holes has held up OK.



The area around the exhaust port under the ring has quite a wide wear mark.



And a lot of staining on the piston itself.



Staining in the cylinder.



And in the transfer ports.

Is this signs of revving it well past its exhaust blow down STA, caster based oil or both?

[husaberg]

Kel brought his air cooled KE125 engine around after running it at the track during Saturdays practice on Av Gas.

And a lot of staining on the piston itself.

Staining in the cylinder.



And a lot of staining on the piston itself.



Is this signs of revving it well past its exhaust blow down STA, caster based oil or both?

I will let Frits and Wob answer but some acetone should remove it nicely

[wobbly]

First reaction is that its a blowby problem with ring seal, as the only place it isnt happening is on the highly loaded thrust face around the Ex port.
It also isnt happening around TDC where the high gas pressure is forcing the ring onto the bore.
So - is the ring true in the bore, slide it down the cylinder with the piston to see if light shows anywhere.
Was the cylinder honed with a dummy head and a torque plate clamped with the studs.
An air cooled Yamaha KT100 will make no power and blow by badly , just like that ,if not finish honed hot with clamp pressure simulating the studs torqued up.
They end up near 0.1mm out of round when cold, and out of the jig.
The hot piston crown may just be a by product of the compromised heat path thru the ring ,to the bore.

[kel]

I also thought this was a blow by problem, but the motor is putting fantastic power to the ground (for a home built bucket), wheel spinning and wheel standing out of corners!
I had made a couple of changes since the last time out -
1. used a different oil, changed from Elf909 to Silkolene Pro KR2
2. rev limiter was lifted to 13250
3. main jet and needle were leaned off a touch, although richened up again later in the day
I was also riding it harder. (The bike showed its appreciation by throwing me down the track twice)

I had the head off a month ago (the last time it was run before this weekend) and the staining in the bore was not present, at that time the rev limiter was set to 12500.

Bore was honed by a kart shop but it was just a straight hone, no jig, no pre-heating, at least I don't think they would have gone to this length for the $20 they charged.
Bike has done enough hours for a new ring, might as well have a new piston as well, and have it all measured and set up properly. Wobbly can you recommend a kart shop that follows your honing procedure.

[TZ350]

An air cooled Yamaha KT100 will make no power and blow by badly , just like that ,if not finish honed hot with clamp pressure simulating the studs torqued up. They end up near 0.1mm out of round when cold, and out of the jig.

I made a set of boring and honing jigs for myself when I was running RD's back in the day. So yes I guess its time to make some more torque plates for our air cooled KE and GP engines. Probably be able to make one jig that suites both engines.

[Haufen]

EVERY weld on a mild steel pipe should be hammered on a mandrel, and the ones in the header linished with a flap wheel, or simply throw away 2 to 3 Hp.

Thanks for that, I was just about to build my next pipe without hammering the welds. (but I am sure my neighbours will understand )

I've got another pipe build question: Do you join the pieces with different angles, header and diffuser for example, with an angled cut, too? Eg the end of the header and the beginning of the first diffuser both cut at 5 degrees each, to make a 10 degree change in direction. In this case, the area of the oval of the first diffuser would have a greater area (because the angle of the diffuser is bigger) and one would get a small step in the pipe.

At the moment, I do not change directions in the pipes where cones with 2 different angles are connected. But it would make life easier if I knew I could, or if I knew that this can be compensated by, for example, altering the cut angle of one part until both areas are the same.

[wobbly]

Yes you can change angles and have an angle cut in the same place.
It doesnt affect the pipes performance at all, but sure as hell makes a huge difference to the form of the build.
Pipes look " dumb " needing a straight join,with angle cuts on each side, and it also means the other angle cuts have to be steeper to accomodate the straight piece.
Here is a cut and join exactly as described - the last diffuser joining the mid, to give a straight line on the bottom.
When the pieces are done in CAD the cone ends are lengthened a little, then the cut goes across the correct length on the centreline, no step and no area change at the joint of the two differing angled cones.

[RomeuPT]

Yes you can change angles and have an angle cut in the same place.
It doesnt affect the pipes performance at all, but sure as hell makes a huge difference to the form of the build.
Pipes look " dumb " needing a straight join,with angle cuts on each side, and it also means the other angle cuts have to be steeper to accomodate the straight piece.
Here is a cut and join exactly as described - the last diffuser joining the mid, to give a straight line on the bottom.
When the pieces are done in CAD the cone ends are lengthened a little, then the cut goes across the correct length on the centreline, no step and no area change at the joint of the two differing angled cones.

What is the maximun bend you would recomend? Even if they are hammered?

I am working on a 125 project, using a YZ 125 2001. Does somebody have info about ignition timing/curve and exhaust dimensions?

Thanks

[wobbly]

Max cut angle on each face should be no bigger than 8* - this will not loose power if the cuts are hammered as per the pic of the RS125 pipe I did.

[TZ350]

http://ignitech.cz/english/aindex.htm

OK I was asked about getting an DC-CDI-Race-2 IgniTec Ignition to fire, this is what I remember about setting one up for the first time.



If there is no spark at all it may be that the Kill switch polarity needs reversing.

ie you have a normally closed switch for ""stop when open"" and the IgniTec might be set up for ""stop when closed"" and ""run when open"", so the Ignitec would need need to be reversed.

Also, from memory the DC-CDI-Race-2 IgniTec does not fire below 300rpm. Push starting is faster than 300rpm but spinning the back wheel over by hand may not be.

A DC-CDI-Race-2 Ignitec is voltage regulated and will not fire below 8 volts (I think) or above 18 volts. Lots of on track miss firing is due to the battery voltage dropping too low when the Ignition is revving out under load.



For accurate timing its important to have the ignition triggering of the back of the lobe, ie on a falling voltage.

You can change the polarity of the pickup here.



For a single with only one coil and pickup and firing once a revolution the setup needs to be changed.



This twin cylinder DC-CDI-Race-2 IgniTec ignition set up will now fire on only one channel, the other side is turned off.



The next step is to work out the base advance.

With the piston at TDC measure the number of degrees between the heal of the lobe and the trigger.

You only need something thats in the ball park to get started with.

An eyeball with a protractor and near enough is good enough here as it gets adjusted later.

Although you are limited to a maximum base advance of 30 deg or 40 on newer software so you might have to move the trigger to get things right.



The 21 deg base advance is entered here.

The next step is to make a flat line graph. Here we have made it 15 deg, only because we know that's what this motor likes.

Next step is to carefully put a timing mark on the flywheel at 15 deg BTDC.

And with a timing light adjust the base advance until the 15 deg flywheel timing mark lines up. When it does, that means the 15 deg ignition line is spot on.

Now when you adjust part of the curve to say 17 deg you can be pretty sure the Ignitec is firing 17 deg BTDC there.

Bucket goes through the setup routine in his post, including a short clip of him using the dyno to spin the engine over while he adjusts the base advance to get his flywheel timing marks to line up.

I got the job of setting up NedKellys IgniTech programmable Ignition. This is how I went about it with one of the Team ESE's bikes.

[RomeuPT]

Max cut angle on each face should be no bigger than 8* - this will not loose power if the cuts are hammered as per the pic of the RS125 pipe I did.

I don't know if it was said before, but about stainless steel, can we use a thinner 0.6 mm stainless steel as strong and ductible as 1mm mild steel? What about welding difficult, prices, performance (as stainless steel has lower thermal condutivity)...

Thanks

[wobbly]

An Ignitech will fire below 300 rpm if its connected to a battery.You can simply spin the rotor lobe back and forth past the trigger by hand and it will fire.
Also the RACE box has a test page where you can press a screen button and fire each channel to check everything is working electrically - past the trigger input.
Once the rotor is spinning, the input screen will automatically show the trigger polarity, so you can change it, or simply use auto that selects the trailing edge by default.
Again I say for the 1000th time - YOU MUST USE A RESISTOR PLUG AND CAP.
Nearly every day I get to fix these bloody things playing up simply due to this rule being ignored.
The other thing that can cause problems is keeping the coil drive wire away from TPS and power wiring,if not done you get false input triggering that makes the rpm as seen by the ECU double
or treble in value - it then invokes the rpm limiter and suddenly we have a " misfire " at 4000 rpm that shows as 12,000 on the screen.
But alot of this can be "seen " on the screen when the engine is running and is easy to diagnose.

Stainless pipes are an absolute bitch to make due to the material stiffness, use 304 as its soft and you MUST use gas purge inside the chamber or the welds will be shit and it will crack.
The material has no performance advantage over mild, it dissipates heat a little differently, but for a road bike it does look nice.