ECU choice....
Turbo Mini Forums

Right, i need an ecu to control the ingition and injection on my 125cc single pot, 4-stoke pit bike.

just a basic set-up dont need any fancy settings, wideband will be the fanciest extra!

the probelms i see is the fact this its a single cylinder...can this be taken into account in the ecu settings? and a coil to run the single plug, which looks like it might have to be OP system?

im looking at VEMS and MS and i think for what am going to use it for and the features that i am going to use on them the biggest decing factor will be the price of a built unit!

while ive got you thinking, does anyone know of a throttle body small enough to suit my app??

cheers for any input...

why not just use a carb? or is it already inj?

Drives
-Ford S-max Mk2 Ecoboost
-Rover 100 VVC #2 - track project

Searching is all you need on TurboMinis

nope its carb, but making the carb blowthrough, id rater use that time and make it injection to give me better control over everything.

megasquirt will do it no sweat. and i'd be supprised if vems wouldnt too, though i know sod all about it.

turbo 16v k-series 11.9@118.9 :)

Denis O'Brien.

All i can say is stop fooking about and get the mini done.

Rick

im abit undecided what to do, its either suck through carb no intercooler, or small intercooler, injection with better control over everything. then wait for the weak links to start breaking befor ending up with something stupid....why cant i just leave things alone and be happy with it?!?!?!?!

Edited by James_H on 22nd Feb, 2009.

If you were thinking of buying pre-built, Microsquirt might be a nice choice due to the small size. But I doubt it's going to be the cheapest option.

Jean

http://www.jbperf.com/

yeah just been looking at the microsquirt jean.

i presume you just set-it up to run a single sylinder enigne in the software?

i am a complete novice with this stuff so you'll have to bear with me , sorry. as for the throttle body, ive been thinking about using one of the ITB's of the Twinks.....?

Actually, I'm not sure if you set it to 1 or to 2 cylinders. I haven't looked at setting up a single cylinder engine but it's just a detail and will depend on how your tach trigger is set. Unless you have a cam signal, you'll need to set it to wasted spark and 2 cylinders (I think).

As for the TB, the one from a Twink is going to be huge for a 125cc since they are designed to work with 250cc cylinders.

Jean

http://www.jbperf.com/

Hi,
Can't see any reason why the VEMs wouldn't do it. The added bonus would be for £70 for the sensor would give you full WBO2 control over fuelling. However the broad is big enough to take 8 injector drivers and 8 ignition drivers, so it won't be small!
Cheers,
Gavin :)

VEMs Authorised Installer / Re-seller. K head kits now available!

WB/EGT gauges. Click here for customers write-up

Visit www.doyouneedabrain.co.uk

My Mini build diary

I've been working on a single cylinder megasquirt project on and off for a while now.

My engine is 300cc, so bigger than yours. However, it's a 1950's single, so the power is about the same as a modern 125cc.

I got hold of a T/B, fuelpump, injector and coil from a Peugeot Jetforce 125 bike. Lots of small bikes with EFI these days, especially Honda, Peugeot and Piaggio. Look on ebay for bargains.

The T/B deserves special mention. it's a lovely little unit made by Bing. The throat diameter is 26mm and it has a built in throttle pot.

You can use Alpha-n for the fueling, or fit a reservoir and restriction in the pressure sensor line if you want to use speed density or a hybrid S/D Alpha-n.

Mine is being set-up with wasted spark, and I'm using an Allegro microsystems hall gear tooth sensor for a crankshaft sensor. http://www.allegromicro.com/en/Products/Part_Numbers/0616/