ESE's works engine tuner

[SwePatrick]

Dynoweekend in my garage, and with my TZR250(242cc)

Ask me anything about the setup, i´ll answer later on.

The setup:
1KT engine
Methanol M1
Lectron (39mm, modified high velocity to my own likings)
Ported Banshee Vforce 4 with 0.35 polini inner petals, and 0.4 polini on outer(oem vforce petals gets soft from methanol)
+5mm rods(RD350/banshee) TZ bigend bearing.
56mm modified Wössner pistons (YZ125 1989)
3xv cylinders, ported by me and adapterplate milled by me.
18-1 in compression
Pipes simulated in MOTA and built by me.
Welded and redesigned crankcase for better direct of flow.
Ignitionsystem is Maxxecu mini, running on a Makita 18v battery.(20.5v)

There might be some more power lurking(partly because i have setup my dyno restrictive), but i called it done, as it is long to next race season, probably need to re-dyno it coming spring.
So i save up on the running hours, as the engine is recently overhauled.

One luxury problem i have had, it lifted the heads earlier.
So i made sturdier studs for both heads and cylinders in toolsteel and heattrated them.
I also cut in a pianowire in the cylinders to give a very good mechanical head seal, since then, no more problems.

All work done by me.


Day one here:



And day two here:

[Gradella23]

Barikit PE-65, 0.8mm ring, ring gap centered over C port, 12mm wrist pin.
24.5mm compression height, 100mm dome radius.
Emot Racing has them sometimes, VRM in Sweden too. VRM just got more in stock.

hello alex, just for your info, I bought a malossi 34.8544 piston with 25mm compression height and 134 dome radius (circa- measured with the comprator on the cnc machine). It weights 74g, but using the barikit pin which has the conical shape of the hole, I dropped it to 71,4g. This is a 5,6 grams gain over the barikit kit. Not bad for a 50cc

[adegnes]

hello alex, just for your info, I bought a malossi 34.8544 piston with 25mm compression height and 134 dome radius (circa- measured with the comprator on the cnc machine). It weights 74g, but using the barikit pin which has the conical shape of the hole, I dropped it to 71,4g. This is a 5,6 grams gain over the barikit kit. Not bad for a 50cc

Nice! What thickness is the ring on that piston, and what sizes does it come in?

[adegnes]

I just discovered small RC hydraulic gear pumps is a thing.
https://goldlandrc.com/product/10mpa...lian-oil-pump/


Could maybe be used for electromechanical continuous fuel injection.
May not even need a barrel valve as the pump is independent from engine rpm.

I've ordered one, will give it a try. Already got some water injection nozzles that should work.
Will be tested independently on a known good engine this time

[flyonly]

My first reaction to the huge Density Altitude variations is that a Lectron is affected by this less than 1/2 a normal carb.
And several guys running Pikes Peak have used a simple hand operated lever to adjust a screw in PJ and watched the EGT during the run to keep it on the money.
But a way cleverer way is that used by Tillotson for their pumper carbs - they use a servo setup from the RC car world with either +/- on board buttons or even remote control for
the screw adjusters.
Even one step cleverer again would be to use the 0-5V RAD output from a digital weather station , programmed thru an Arduino or Raspberry device to auto correct the real time EGT input by controlling
the PJ servo on top of the carb.

Wobbly

Which model carb would you choose to use?


Sent from my iPhone using Tapatalk

[wobbly]

Fly , depends upon the engine config and the end use.

[diesel pig]

Fly, I must say the more I find out about the lectrons. The more impressed I am with them. Especially with the modern ones.

[F5 Dave]

Ooh, let's play this game in reverse.

How about one of those tubes types where you wind a fuel damp wick into the airstream?

[Gradella23]

Nice! What thickness is the ring on that piston, and what sizes does it come in?

1mm ring, starts from 39.93 sel. 0 to 39.97 on sel. C, but at the moment it looks like the only two available are A and B (from 39.94 to .96)

[adegnes]

Continuous high pressure injection could be the ticket for higher nitromethane percentages. Better atomization, less fuel just passing through the engine unburnt.

Variated landspeed bike is a special use case. I need to be able to climb from somewhere early in the powerband to peak power rpm once, then steady state WOT at peak power rpm for 5km or so.

[husaberg]

Ooh, let's play this game in reverse.

How about one of those tubes types where you wind a fuel damp wick into the airstream?

everyone's wanting to build a better mousetrap...

[diesel pig]

everyone's wanting to build a better mousetrap...

I have have personally come a cross rats that I think would not be phased by a direct hit by the gun one.

[TZ350]

Continuous high pressure injection could be the ticket for higher nitromethane percentages. Better atomization, less fuel just passing through the engine unburnt. Variated landspeed bike is a special use case. I need to be able to climb from somewhere early in the powerband to peak power rpm once, then steady state WOT at peak power rpm for 5km or so.

My previous limited experience with a two stroke and Nitro on the dyno. Is that, it was good for additional low down torque and for filling in the hole just before getting up on the pipe. Once the engine started coming anywhere near maximum torque it was best to stop adding nitro. It sure looked like it would give the bike some extra lift coming out of corners. A real power band widener. It would be interesting to adjust the engines compression/ignition properly for Nitro. Maybe I will try it one day.

.
NITRO METHANE
.
Too days dyno experiments were with my Suzuki RG50 powered Bucket Racer and raw Nitro.

I have always theorized that with a correctly jetted two stroke running properly on race gas or similar one can just squirt raw Nitro Methane into the bell mouth and you will see a power increase with out any air fuel mixture issues. The reason is, that raw Nitro carries just a little more fuel than oxygen so as well as adding oxygen for more power it effectively richens the ingested mixture too.



The experiment was a bit crude. Just squirted the Nitro in. Blue line is Av Gas only and correctly jetted for max power. The red line is with Av Gas and Nitro squirt. The red line shuts of early as it goes over rich. For Nitro to be useful you would need ignition and mixture control. So the conclusion is that with a digital ignition and power jet control Nitro could be a very viable option, pity Nitro is illegal in our racing class.

But anyway if you have ever wondered if Nitro could be a good thing with two strokes then this experiment suggests there are real possibilities there.

[136kg136ps]

So could a switched PJ be used to add the nitro at the desired RPMs?
I could see adjusting timing to coincide with the nitro but compression would be a bit beyond me.

[Frits Overmars]

pity Nitro is illegal in our racing class.

Pity?
My limited experience with nitro dates from testing a blown dragster on nitro as technical editor / testrider for Moto73 in 1976.
My most vivid memory after all these years is not the acceleration, but the hellish pain when you get nitro fumes in your eyes.
I suppose inhaling the stuff can't be very healthy either. And if you don't care about the corrosion in your lungs, think about the corrosion in your engine.