Zongshen RX3 (ZS250GY-3): Delphi Multec EFI
 

The Zongshen RX3 employs Delphi Multec Electronic Fuel Injection, which is documented at the Delphi website.

http://www.delphi.com/manufacturers/...wertrain/small

http://www.delphi.com/docs/default-s...f.pdf?sfvrsn=0

http://i442.photobucket.com/albums/q...ps725214a5.jpg

Single cylinder motorcycles, such as the Zongshen RX3, employ a system using the MT05 engine control module (ECM).

http://www.delphi.com/manufacturers/...owertrain/mt05

http://www.delphi.com/docs/default-s...f.pdf?sfvrsn=0

This ECM receives information from a number of sensors.

Zongshen provides the crank sensor, which is located inside the Zongshen NC250 engine.

The engine temperature sensor measures coolant temperature, and is located in the thrermostat housing under the fuel tank.

The oxygen sensor is attached to a bung on the exhaust header.

http://www.delphi.com/manufacturers/...in/mini_swh_ox

http://www.delphi.com/docs/default-s...f.pdf?sfvrsn=0

The manifold absolute pressure (MAP) sensor, manifold air temperature (MAT) sensor, and fuel injector are attached to the intake manifold.

The throttle position sensor is incorporated in the Delphi throttle body.

http://www.delphi.com/manufacturers/...rain/etc_tb_sm

http://www.delphi.com/docs/default-s...f.pdf?sfvrsn=0

A fuel pump, which provides pressurized fuel to the fuel injector, is located inside the fuel tank.

http://www.delphi.com/manufacturers/...rain/sm_eng_fm

http://www.delphi.com/docs/default-s...f.pdf?sfvrsn=0

The Delphi Small Engine EMS Service Manual is located at the following link.

http://www.huntermotorcycles.com.au/...l%20Manual.pdf

Many Harley Davidson motorcycle employ the Delphi Multec EFI system. The following link describes how Delphi EFI systems work in the multi-cylinder HD engines.

http://www.nightrider.com/biketech/m...asics.htm#null

Many Yamaha motorcycles also employ electonic fuel injection. Although the Yamaha EFI systems are different from the Zongshen EFI system, one can learn many troubleshooting techniques by watching the following Yamaha videos. ;)

https://www.youtube.com/watch?v=fujeAFAjb4A

Here are a several videos showing how to clean a fuel injector.

https://www.youtube.com/watch?v=rLuAVhVp44Y

I'm geeking out over this stuff.

I was surprised (and impressed) to learn that Delphi offers a stepping motor throttle body, rather than a throttle cable. That would create drive by wire that is so common in cars now.

I don't want that level of complexity on my bike, but it's cool nonetheless.

The stepper motor in this case is likely for idle speed . I think it would still use a throttle cable for throttle input. Idle steppers allow air to bypass the throttle blade and maintain idle throttle position sensor voltage

Thank you for your input, Racer. :) I'm pretty sure you are correct regarding the stepper motor being employed only for idle speed of the RX3.

The Multec MT05 webpage indicates this ECM employs idle air control (IAC), which undoubtedly utilizes the stepper motor.

http://www.delphi.com/manufacturers/...owertrain/mt05

http://www.delphi.com/docs/default-s...f.pdf?sfvrsn=0

The Delphi webpage for the Multec MT05 contains this information.

Serial Communication feature flexibility: Controller Area Network (CAN) or KW2000

http://www.delphi.com/manufacturers/...owertrain/mt05

I just found a web source which indicates you can use an OBD2 reader for all late model cars to communicate with the Delphi MT05 ECM. :tup: I will do some more research, and post my findings later. :)

In the meanwhile, here are several links to OBD2 and CAN scanners. You can get one from China for $16.25, delivered. :)

http://i.ebayimg.com/00/s/MTUwMFgxNT..._id=880000500F

http://www.nationaltoolwarehouse.com...IuJxoCATfw_wcB

http://www.ebay.com/itm/Autel-MS300-...p2054897.l4275

http://www.harborfreight.com/can-obd...0693-html.html

Apparently, you can also borrow an SERT scanner, and export the data to free graphing software. ;)

Perhaps we can use this $9 cable to connect a computer directly to the Multec MT05 ECM. ;)

http://www.ebay.com/itm/VAG-COM-KKL-...p2054897.l4275

http://image4.pushauction.com/350/35...beeaa19e04.jpg

Of course, you're right. I got a little too excited. :D

That would be really cool. I just received a bluetooth scan tool from my nephew (he's awesome), and it communicates with a smart phone. I'm really looking forward to trying it in my truck, to observe real-time data. I'll let you know how it works.