300cc Kit

[Juanro]

Hi Tako, the kit works as advertised. Components are of good quality, except de MAP sensor, wich I had issues at first and later it stopped working sudenly in the middle of nowhere; lucky me (or perhaps, I'm farsighted haha) I had my netbook with me and was able to change the ECU from Speed Density (wich uses MAP) to AlphaN (wich not) and limp home. I replaced it with a generic unit (a common replacement unit for many cars), and all is fine now.
This was a kind of an educational project to me. I like that I can see and modify almost any parameter in this ECU, not only the VE map, but starting, warming up, ignition advance, acceleration enrichment, and many more. Just a couple things are preset in the firmware (wich the vendor did not sent to me), and really minor ítems wich are not show stoppers.
My goals were:
- Get rid of the Keima carburetor wich was starting to fail and have no replacement here
- Get a good and reliable cold start
- Get the posibility to alter mixture and engine parameters on the fly, much easier than fiddling with jets and needles in the carburetor
- Get the self adjusting of mixture to accomodate climate and altitude changes
- Educate myself on the details of EFI and have fun in the process
I'd say that it fullfilled all of this goals, but also that those are not everybody goals.
I'm very happy with the result, having put over 8000km now with the kit working, taken two long trips, ran many times all day long in different situations, and so on.

[NzBrakelathes]

THats cool
Yeah I’d say you’d and would spend many hours learning etc and that’s not for most people as they want it all now and perfect and at a cheap price lol.
I’d say you might be able to do similar tuning like if you had that expensive software for the RX3 - in a way you’re better off or another way to see it is just more stress.
For me I’d think not worth it unless I wanted or needed more education or experience then I would invest the time (money is less stressful in some ways) but the time would surely be a lot
Interesting stuff! Many have tried to EFI swap small bikes but failed or stressed

[Juanro]

Yes, that's it. If you want an easy drop in replacement for the carburetor, this kit is not. And, to be honest, they say it plainly in the Aliexpress ítem description.
But for me it turned out nicely, I uploaded a recent video of myself taking a scenic trail here in Córdoba, that's 700km away from my home, and I venture in the middle of nowhere, so you can see I'm very confident in the workings of the EFI (or at least in that my mechanic insurance will pick me up in case of a mishap!)

[2LZ]

That's kinda funny really. Sometimes I wish my RX3 had a simple carb on it to be able to quickly change jets around mods and also, to get rid of that dang occasional dying when pulling up to a stop.

[Juanro]

Originally Posted by 2LZ

That's kinda funny really. Sometimes I wish my RX3 had a simple carb on it to be able to quickly change jets around mods and also, to get rid of that dang occasional dying when pulling up to a stop.

I guess that's because you lack the open software to tune the EFI for the "propietary" Delphi; but I can take my laptop out, plug the cable, make a change, and be back riding in a minute, and with my hands not smelling of gas, haha

[NzBrakelathes]

So you should be able to tune and run a 298cc kit

[sqwert]

I'm fortunate to have a friend with a dyno and all the electronics who makes his living tuning engines. Next vacation I'm riding the RX3 to Texas for a full dyno tune. Really not a big deal since DELPHI is used on so many other bikes and machines, including Harley. He set me up with a laptop for Microsquirt since I have a pair of TW267s (stroked and bored 200s) with Microsquirts. Better from idle to redline than any of the carbs I've tried, including a Weber--the best ever. Quicker throttle response, more torque, more horsepower, less fuel, all at the same time. A particular carb may have more of one attribute, but gives up on the other three to beat Microsquirt at one.


Whether or not the RX3's stock Delphi can run a 298 depends on the injector flow capabilities. Might need a bigger injector or more fuel pressure to yield a higher fuel volume.

[2LZ]

Originally Posted by Juanro

I guess that's because you lack the open software to tune the EFI for the "propietary" Delphi; but I can take my laptop out, plug the cable, make a change, and be back riding in a minute, and with my hands not smelling of gas, haha

LOL! but I like that gas-all-over-me scent and the eventual headache! ;-)

[whiplash]

Originally Posted by NzBrakelathes

https://www.magnumtuning.com/en/deta...-chip/zongshen

Hard to tell, is this capable of rich/lean adjustments across the board? I know it's old thread, sorry..

[NzBrakelathes]

Originally Posted by whiplash

Hard to tell, is this capable of rich/lean adjustments across the board? I know it's old thread, sorry..

I think only up to 6000 RPM as beyond that it is a fixed map in ECU.

[jthewood]

Will the 300 kit work on the TT250?

[rjmorel]

Originally Posted by jthewood

Will the 300 kit work on the TT250?

Doubt it cause RX3 is watercooled , TT250 is aircooled totally different motor designs, rj

[2LZ]

Originally Posted by jthewood

Will the 300 kit work on the TT250?

Nope. Two completely different motors. So far there's been no sign of a big bore kit for any CG motor.

[Juanro]

The 250cc CG engine is already a "big bore" CG version, the original one was 125cc ...

[2LZ]

So, is most everyone is running the stock exhaust (with cat) with the 300 cc kit???