ESE's works engine tuner

[wobbly]

With the Alky system I tested the arc over voltage was around 28KV, and this dropped to around 12Kv during the burn phase.
This CDI system with double the capacitors and a really big coil ( a Crane as used in NASCAR ) had 4 times the burn duration of the stock
single CDI setup, it pulled around 5A from the DC supply where a single was all out at 1.5A.
I read somewhere that the limiting factor in a CDI is the capacitors ability to supply the required power fast enough, this being a quality set by the ESR
of the part, so I would imagine that the actual power supplied to the gap ie Watts = V*A is close to constant.
Thus when we have over twice the gap voltage at arc over, we would have less than 1/2 the current, and during the burn - visa versa.

[senso]

In my limited testing, low ESR and low ESL is the key for a good spark.
I have already tested some metalised foil caps, rated to 630v, and 1uF makes a nice spark, but two in parallel makes a sweet blue spark with a nice sound to it.
From my simulations and for the intended stator the best value for maximum charging is 4uF.

[peewee]

i never could figure out why a methanol engine can run fine even with raw fuel pouring out the end of the pipe. gas engine will only run for a very brief time in the same situation

does anyone care to explain why high performance engines always seem to use alot of oil in the gas ? i believe jan once said he used about 5% oil. i use about the same. what is the advantage of 5% versus something lower like 3 or 2% ? does the extra oil transfer heat to the cylinder walls better ? do the rings seal better ? does it lower the temp of the intake mixture ? better combustion in the head ? does it cool down the piston top more ?

[speedpro]

Dyno tests I've heard about more oil equalled more power. Do you really need to know why?, apart from curiosity of course.

[husaberg]

Dyno tests I've heard about more oil equalled more power. Do you really need to know why?, apart from curiosity of course.

Bell covers it with Dyno tests.

[peewee]

gordon jennings also did the oil ratio tests back in the day with castor oil. his conclusion was it gave more power but do synthetics oil work the same way ( more oil=more power) ? besides more power is there other reasons , like the piston has less chance of siezing ? if you look at a service manual like ktm they say to use only about 2.5% oil even for the 125cc mx engines. im trying to understand why this is. to me 2.5% doesnt seem like enough

i just remembered something from jennings oil test which was alot of years ago but didnt he say the more oil=more power may not be true for synthetics because of the cleaning agents and stuff they use ? granted the new oils are probly a bit different

[F5 Dave]

2.5% is 40:1 and what I run in big bore trail bike. Its peachy and never wears, but you're (I'm) never on the gas for that long so there's always some oil about.

125mx in the hands of a fearless kid? Well perhaps KTM want to sell some parts.

[TZ350]

i never could figure out why a methanol engine can run fine even with raw fuel pouring out the end of the pipe. gas engine will only run for a very brief time in the same situation

My take on it is that the raw methanol that is pouring out the end of the pipe is un-vaporised fuel so is not contributing to the fuel/air mix. When that happens you need to reduce the latent heat of evaporation of the methanol by blending it with acetone, ethanol, or unleaded petrol so the motor runs warm enough to properly vaporise the fuel load. It is possible to run a 2T so cold that the methanol is running lean on the plug but pouring wet out the exhaust pipe, richening it up only makes it colder and leaner while wetting the riders behind. Been there done that.

does anyone care to explain why high performance engines always seem to use a lot of oil in the gas ? i believe jan once said he used about 5% oil. i use about the same. what is the advantage of 5% versus something lower like 3 or 2% ? does the extra oil transfer heat to the cylinder walls better ? do the rings seal better ? does it lower the temp of the intake mixture ? better combustion in the head ? does it cool down the piston top more ?

My take on this is, apart from the apparent truism that more oil = more power, there is the time it takes for the oil to pass through the engine to think about. A high revving engine will pass its oil load quite quickly compared to something more sedentary and is why the performance engine enjoys a richer oil mix and feels properly lubricated compared to the way it would feel using a suitably lower oil mix from something more pedestrian.

Team ESE run 20:1 or 5% and when I was running a TZ it was 20:1 Castrol R on short circuits and the factory recommended 12:1 for running in and 16:1 for demanding conditions, I guess like when you're on WOT and peak rpm for a lot of time. It was basically, use as much oil as you can get away with.

[ken seeber]

does anyone care to explain why high performance engines always seem to use alot of oil in the gas ? i believe jan once said he used about 5% oil. i use about the same. what is the advantage of 5% versus something lower like 3 or 2% ? does the extra oil transfer heat to the cylinder walls better ? do the rings seal better ? does it lower the temp of the intake mixture ? better combustion in the head ? does it cool down the piston top more ?

When I was with Orbital and working with Mercury on what was to become the Optimax, they told us a story of when they used to run (carb V6 engines) in a 24 hour boat race in Rouen, France. They had lots of seizing issues, eventually solving it by running on 8:1. To assist starting, they drained the carbs and refilled them with straight petrol. Can't comment though on if they had more or less power.

If there aren't any deto issues, then one could imagine it shouldn't be any worse as the calorific value for most fuels and oils are quite similar. This statement doesn't take into account the stoichiometric nature of each though.

[Muciek]

Wobbly, have You tried something like this?



Just need powerfull inventer in CDI module (don't know will ignitech could handle it) module and 2 HV (4 in twin engine) microwave oven diodes.

I was testing similiar one but signal generator failed somehow.

[senso]

With such a big spark isn't there and extre risk of melting a hole in the piston due to the added heat?
Or even the spark jumping from the sparkplug to the piston crown?

[Frits Overmars]

With such a big spark isn't there and extre risk of melting a hole in the piston due to the added heat? Or even the spark jumping from the sparkplug to the piston crown?

No, and No. But the plug electrodes will disappear while you wait.

[Muciek]

With such a big spark isn't there and extre risk of melting a hole in the piston due to the added heat?
Or even the spark jumping from the sparkplug to the piston crown?

Spark it's not long like it appears on video , it's just A LOT brighter and fatter and as You could hear a lot nosier.

You can see it better on my video https://www.youtube.com/watch?v=QgmKHk5OOfc

No, and No. But the plug electrodes will disappear while you wait.

Frits is right (as always ) here are photos of standard plug after some use (Nyemi photo)

[wobbly]

I did a series of tests on full synthetic and semi syn oil for KT100, the results are in here somewhere.
Bottom line is that for very high temp Avgas or aircooled running unleaded, the full synthetic is useless.
The ester based castor/synthetics like Elf 909 or Motul Kart offer much better protection when pushed really hard in hi temp end uses.
They used to run R30 at 16:1 in karts, but now with unleaded the 909 at 20:1 makes more power, and there is very little wear.

Methanol will make no less power when run +20% over stoichiometric, petrol wont even run at this level.
You can run insane levels of com with a rich Methanol mixture as the unburned fuel cools everything and stops deto.
The effective octane of rich Methanol is over 130, and with its very high latent heat its great for all types of 2T, especially Aircooled.

I have not tried the huge Plasma type sparks, with such good results with the twin CDI thing and big coils, I don't see the need.

[speedpro]

Methanol will make no less power when run +20% over stoichiometric, petrol wont even run at this level.
You can run insane levels of com with a rich Methanol mixture as the unburned fuel cools everything and stops deto.
The effective octane of rich Methanol is over 130, and with its very high latent heat its great for all types of 2T, especially Aircooled.

Old air cooled 4Ts with a turbo like methanol as well. I made a little valve for mine that opened with boost and tipped in methanol. My mates blown big block ran 100% methanol and crazy compression and boost. At pre-launch revs it had fuel pouring out the headers and at idle(1500+rpm) in the pits it formed ice on the intake manifold. As mentioned tuning methanol has a few quirks. Real rich made the plugs stay pure white as the fuel washed them then as you leaned it off you got a little bit of colour and if you kept going they got coated with melted aluminium. We tuned until the coating on the plug threads was burnt off the first 2 threads. Kept an eye on the pyro data logger as well of course.

Anyway, , back to 2Ts .