Question regarding 15RC ECU, phonic wheel and alternatives

[lazlokovacs]

Moving on from my recent Honda nightmare I'm seeking repentance in the guzzi world by rebuilding my Cali engine.

Reciprocating parts are on their way back from being balanced and all is good.

So...

1100 Cali vinatge engine

I'm using Joe Caruso's steel gears, which mean I have to lose the phonic wheel and sensor.

My question - is there another way I can get a signal to the 15RC ecu that the ECU will recognise and understand?

I was thinking about something like a sachse pickup mounted on the alternator nose, but I want to know if the signal from the Sachse will be comprehensible for the ECU or if it's possible to mod it in any way?

Hoping someone out there has an idea!!!

Cheers

 

[Antietam Classic Cycle]

I see on Nolan Woodbury's site that Joe offers gears for the "V11 injection". Wouldn't those be for engines with a phonic wheel?

https://woodburymotomedia.com/moto-guzzi-timing-gears-by-joe-caruso/

[lazlokovacs]

I see on Nolan Woodbury's site that Joe offers gears for the "V11 injection". Wouldn't those be for engines with a phonic wheel?

https://woodburymotomedia.com/moto-guzzi-timing-gears-by-joe-caruso/

those are the gears I have, but there's no room for the phonic wheel sensor, so an alternative way of getting a trigger must be found

[Murray]

those are the gears I have, but there's no room for the phonic wheel sensor, so an alternative way of getting a trigger must be found

So the recess in the cam wheel is not right? I guess the obvious question is what does the V11 do for cam position information?

[Old Jock]

Sounds like you've got gears for a carb engine and are trying to use them on an injection bike.

Joe does supply gears that accomodate the phonic wheel, but Joe's gears are expensive so I understand your logic. Ok that's a HiCam but I have Joe's gears on a Sporti as well, just don't have any pictures



I can't tell you about the later Sachse system I have one of his trigger systems on an LM 1000. It's optical and uses 2 sensors. A sensor for each cylinder and is crank mounted, so it's a wasted spark, but not the type that can lead to Roast Goose. The Sachse system doesn't know when it's on the compression or exhaust stroke being crank not cam mounted and it's 2 speed signals



Theoretically I think it could be possible to use it but not without some serious changes to the ECU programming and possibly further hardware.

Probably an easier way to go would to either go back to chain, mount the Phonic wheel and keep the injection.

Much as I love Joe's gearsets, the chains work well

If hellbent on keeping the gears I'd probably junk the injection and go to carbs.

Just what I'd do, of course there will be other ways to achieve it, but I just don't know enough about ECUs. I'd pop a mail to Cliff Jeffries on MyECU fame he might be able to offer some advice on your predicament

John

[lazlokovacs]

thanks Jock,

I'm familiar with the Sachse system, I was hoping to keep the ECU in charge of spark, and wondering what kind of signal it receives from the phonic wheel. Can't be too different from the signal from the Sachse I would have thought. Of course the Sachse pickups would have to be mounted 180 degrees apart to mimic the gap in the teeth of the phonic wheel. (happening two times per crank revolution)

 Carbs are a possibility, and I've always erred on the side of carbs, but since Beetles maps have come along I'll take FI any day.

 

[Kiwi_Roy]

The Phonic wheel has one missing tooth that's what the ECU uses to sync to, The ECU counts teeth from the gap and fires the individual spark and injector at the appropriate spot.

[lazlokovacs]

The ECU counts teeth from the gap and fires the individual spark and injector at the appropriate spot.

Ahh... good info... Hmm i might just run the fuelling from the ECU and fixed spark from a sachse on the crank.

Or just put my trusty old PHMs on the thing...

Hard to decide, carbs are nice in the progression phase, and easy to fit a 'cruise control' (the screw on the throttle grip...!) 

But I do really like a well mapped FI guzzi. They tend to be faster too

Anyone got a jetting recipe for a flywheel lightened 1100? Jackson maybe?

[Old Jock]

thanks Jock,

I'm familiar with the Sachse system, I was hoping to keep the ECU in charge of spark, and wondering what kind of signal it receives from the phonic wheel. Can't be too different from the signal from the Sachse I would have thought. Of course the Sachse pickups would have to be mounted 180 degrees apart to mimic the gap in the teeth of the phonic wheel. (happening two times per crank revolution)

 Carbs are a possibility, and I've always erred on the side of carbs, but since Beetles maps have come along I'll take FI any day.

I agree that the Sachse system is similar, I don't understand how mounting the sensors 180 degree apart is required you've lost me there.

The blank wheel and trigger is probably not so well suited to firing the injectors as well as triggering the coils, I think.

With the toothed wheel (let's say 60 teeth are on the wheel, I can't be bothered to count them) when the trigger passes the missing tooth it knows it's at a certain point in cam rotation, it then also knows as every tooth passes what the speed is (frequency) and the cam has moved 6 degrees or 12 degrees of crank rotation. As far as my limited intellect can gather that's enough data to know when to trigger the injector.

The Sachse rotor though only knows where it is once (or possibly twice if you count leading and trailing edge triggers) in the crank cycle. I'd imagine from that something could be made to trigger an injector for a constant RPM, the ignition and injector for each cylinder would be programmed to fire at x milliseconds after (or before) the leading edge trigger and the leading edge and trailing edge time difference would tell the ECU the rotor speed.

Under hard acceleration/deceleration, I'm not so sure, you'd then need to look at the acceleration/deceleration of the crank speed and the clock/reaction times of the ECU. I'm sure it could be done, but I'd think you'd be starting pretty much from scratch.

If a toothed/gapped wheel was mounted on the alternator nose or flywheel (but it gets a bit mucky in there) using a magnetic/reluctance/Hall effect or optical sensor and an interposing box between the signal(s) and the ECU it could work I'd guess. The interposing box would take whatever signal came from the trigger and transposed that to a signal identical to what the ECU was expecting.

I couldn't do that but from my limited knowledge but sure it would be prefectly feasible.

As well as Cliff Jeffries was not there not a guy on here who built and ECU emulator? He'd be worth routing out and talking to as well.

It would be an interesting project

[guzzisteve]

I think you can blame THAT Honda now!!

[lazlokovacs]

Jock,

I totally misunderstood, I thought the wheel was giving the same information as the sachse light... ie just a pulse once every cam revolution....

I get it now, each tooth creates a frequency, so it always knows exactly where it is... that's how it can advance and reatrd the ignition.

I'm thinking using the ECU for fuelling and the Sachse for spark could work

Assuming the ECU wont s--t the bed if it doesnt make/sense an actual spark.

I know from experience that the ecu can be quite happy the other way round, ie just making spark while a carburettor fuels the bike.

[Old Jock]

Jock,

I totally misunderstood, I thought the wheel was giving the same information as the sachse light... ie just a pulse once every cam revolution....

I get it now, each tooth creates a frequency, so it always knows exactly where it is... that's how it can advance and reatrd the ignition.

I'm thinking using the ECU for fuelling and the Sachse for spark could work

Assuming the ECU wont s--t the bed if it doesnt make/sense an actual spark.

I know from experience that the ecu can be quite happy the other way round, ie just making spark while a carburettor fuels the bike.

Forgive me here if I'm trying to tell you something you already know, I just don't want you to embark on a fruitless project. I also don't want to sound so negative, I'm sure there are ways around the problem, I just don't know of an easy one that wouldn't involve a lot of work

The Sachse wheel is running at crank speed the Phonic wheel at cam speed.

The Sachse trigger completes 2 revs per engine cycle, the phonic wheel 1 rev.

Each cylinder on the Sachse ignition recieves its own signal off it's own dedicated pickup, that's why there are 2 optical triggers and why the Sachse system is not a dangerous wasted spark system. The Sachse wasted spark occurs 360 deg from when the cylinder requires a spark to ignite the mixture. The dangerous wasted spark systems have both cylinders sparking no matter which cylinder requires the spark.

I'm still struggling to understand how you could use the ECU to control the fuelling.

Will the ECU not still need some form of reference to know where the engine is on the cycle to trigger the injector pulse at the right time to the relevant cylinder? I'd have thought it would but I'm no ECU expert

Carbs are easy (in this regard) they are passive devices and work purely on pulling in the mixture when the cylinder creates a suction or negative pressure.

FI sprays the fuel in at given time under positive pressure for a set duration.

The ECU has to know where the engine is in its cycle, in order to command the injectors to fire at the right time. To do that it needs a reference from the engine, be it a toothed wheel or something else.

At least that's the way I see it, but I've been wrong before 

John

[lazlokovacs]

Jock- yes you're absolutely right re the ECU, it's been a couple of years since I looked at a map on tunerpro and my FI chops have obviously become a bit rusty...!! (slaps forehead)

I agree that the cleanest option is to take the old school carb route in this case, taking the trigger off the crank nose with the Sachse

I've got all those bits in a well labelled box somewhere so it shouldn't be hard

thanks for talking me through my brain freeze!!

[lazlokovacs]

update, it turns out that the steel gears I have are actually for a FI bike in any case... (slaps forehead even harder)

So... er... I'll just hook everything up to the ECU and ask beetle for a map and life will be sweeeeeeeeeeeet again.

Thanks again for coming down this pointless alley of my ill-thought out thought process, I'm putting it down to Honda PTSD

Can't wait to get back on the guzzi and start ticking off some miles

Ride safe