Rs125 2 stroke EFI build

[chili023]

Good Day,
we are building a 125 and 250 Aprilia RS with rusEFI for the Track. We baught the micro rusEFI and are just getting started to set it up.
Due to Fuel compensation that is based on exhaust belly temperature. We need at least 3 type K Thermocouples.

our setup:
DD2 125 kart cylinder
Gianelli Exhaust with EGT and Lambda
BMW T310 throttle body
Bosch Injector

34Hp on the wheel with Keihin 38 PWK carburator

We will setup everything in the next week and keep posting here.

I have one question for the forum. We need at least 3 but for calibration up to 6 Thermocouples.
If we use Max31855 we will have 6 CS cables correct?
Seams a lot of wireing.
What would you do? TypeK to CAN moduls?

We keep you guys posted.

[AndreyB]

Just got from Berlin two days ago!

Something similar to https://racerotax.com/125-dd2-max/ ?

Yes, TypeK to CAN module would be an option. Technically we have dual-channel TypeK on https://www.shop.rusefi.com/shop/p/dual-channel-wbo but we do not have great firmware for it only hardware.

[Dron_Gus]

AEM 8ch https://www.aemelectronics.com/products/dashes_and_gauges/dashes/aemnet_can_bus_expansion_modules/parts/30-2224?srsltid=AfmBOoqlcteaOhLTIGbU9MEaizorJfTI2rTMeud36xe0bWDIK_A_WDYF ?

[chili023]

Just got from Berlin two days ago!

Something similar to https://racerotax.com/125-dd2-max/ ?

Yes, TypeK to CAN module would be an option. Technically we have dual-channel TypeK on https://www.shop.rusefi.com/shop/p/dual-channel-wbo but we do not have great firmware for it only hardware.

Yes excatly that. We want to try some things this winter.

[chili023]

AEM 8ch https://www.aemelectronics.com/products/dashes_and_gauges/dashes/aemnet_can_bus_expansion_modules/parts/30-2224?srsltid=AfmBOoqlcteaOhLTIGbU9MEaizorJfTI2rTMeud36xe0bWDIK_A_WDYF ?

A bit to pricy for us. But thanks.

[chili023]

How would one start to create a correction of the fuel map based on Belly temp?

Just started wiring. TPS and Injectors are done.
Is an Optical IR gate a good idea for crank position? I want to use a 60/2 wheel.

[chili023]

Is there anything that should prevent me from using an IR Gate as a Cranksignalsensor with a 60/2 wheel?
It is 5V.

IR Gate.jpeg

[chili023]

OK first run no problem. Here are the details

Used were the following parts
Lexus Coil for 2GR-FSE engine
BMW G310 Throttle body with bosch injector 280158211 (411ml/min @2.5 bar) workes plug and play. TPS sensor already attached
RAVE exhaust valve was actuated by gpPWM
original CLT of RS125 (0°1700OHM / 22° 650 OHM / 100° 60 OHM)
Hall Sensor of a Rotax Sled (Honeywell Sensor SNG-SPCM)
Fuel tank of a RS4 125 (4 Stroke 125cc EFI version) with fuel pump (gives 2.5 bar from 9-16V)
Trigger wheel is a sheet metal ring. 36-2 teeth.
No IAT or MAP yet.

Control mode Alpha/N
VE was calculated in 1D/0D simulation and copied over to the ECU.
Ignition from the carburetor bike.

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We calibrated injector dead time over voltage and punched in some estimations for CLT enrichment. After that we defined TDC and set timing base advance.
Just one push on the starter and the thing ran. I couldn´t believe it. We let it heat up and drove on the dyno a bit. After a couple of heat cycles and some preparation for the runs we startet the first WOT pull. The goal: visually checking lambda and EGT on the Dyno Software and abort if hit a limit (lambda >1.2 , EGT > 700) rev limiter set to 10.5k.
A solid 28hp on the wheel. I was amazed. Lambda and EGT were pretty good but on the rich side.

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Here compared with the carburetor bike (same exhaust with Airbox)

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We checked the engine and started the tuning. She reacted great on timing and less fuel. In the end we reached 31 hp with Airbox and 32 without Airbox. There is still some power in the intake duct but for a start this is amazing. The calculated ve worked amazing just simple changed had to be made. This still has to be drivable on the track, but for a proof of concept this was a success. I will keep you posted.

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[chili023]

Day 2 on Dyno.
Miner VE changes but still to rich everywhere. Encountered that we used EOI of -180deg yesterday so the fuel finished just before the reed valve opens. we changed that to -30 so the injection is just over when the reeds close.
Also ran a 0-100% TPS test. The TB seems to be to big.

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The 39mm TB still gives 30hp at 40%.

[chili023]

The bike is coming of the dyno and will be fully rebuild until march. We are building 2 equal bikes one carburetor conversion and on fully rebuild.
ECUs will be uaEFI. Throttlebody will be changed to a smaller size. 32mm would be ideal. If anybody knows a 32 mm TB with poti and bosch injectors that would be nice.
Merry Christmas.

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[chili023]

We are planing inputs and outputs for the ECU we have some quick questions for the pros @AndreyB.
We wat to use uaEFI as a base. We want to just eliminate some parts and want to add some others. Hardware side is clear we want to know if the software side will give us trouble.

We want to eliminate
WBO
IGN5-6
INJ5-6
VR circuits and chip
bluetooth module

We want to add:
4x MAX31855. The uaEFI already has a MAX31855 on board. We would just add 3 more to it
some 0-5V inputs

This shouldn`t give us any problems correct?

[AndreyB]

https://github.com/rusefi/rusefi/wiki/I-have-an-idea

[chili023]

Very helpfull as usuall.

For the next guy that ask. Maybe try something like:
"Yes it is possible you have to check this and remember that. I would start there or try this first"
Or :"I think it isn't because x, but you can try this and that first that will tell you if it is or isn't."

Nobody wants you to do it. I was jsut asking for your 5 cents.