EFI conversion on a Gen-1

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The Speeduino could handle 2 O2 controllers in code but i`m not sure if the signals could be combined. With a four-in-line with one manifold is much easier to install the O2 sensor.

I could run 1 O2 off of the rear right cylinder and run 1 in the exhaust to see if there isn't a large deviation between that one cylinder and all four. But let`s not get carried away :D
you can weld O2 sensor bung on each pipe and install plugs until you decide to check each cylinder.
 
Yes, I`ll likely keep the one in the mufflers and add one or 2 on the rear downpipes. The front ones are dual walled so that`s a lot harder to weld a bung to.

Since the trigger signal still wasn't perfect, I added a second pick-up. I suspected that the RPM spikes and losing sync was caused by both the ignition system and speeduino sharing the same pick-up. So the new type pick-up you see on the right is used for the Ignitech ignition and the left one is used for the Speeduino. As you can see, the left unit has two pick-ups in one, only the top one is used there.

30.JPG

But again, no luck! Still seeing spikes. So I needed to validate the Speeduino hardware and especially the VR-conditioner. The pick-up coils are of the variable reluctance type which sends a small electronic signal in case it detects a ferrous object. More on it here:

https://en.wikipedia.org/wiki/Variable_reluctance_sensor
So I needed something resembling the flywheel and with edges that count as lobes. After some thinking, this is what I built :)



So that`s a saw blade powered by a small electronic motor (which was part of the throttle bodies` fly by wire system). And with that, I was able to conclude the electronic components are fine.


So the next theory is the signal gets interference from the magnetic field generated by the flywheel`s magnets and the alternator coils. I will test some shunt resistors to reduce the signal. To be continued :)
 
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Do you have a screenshot of the spikes and the signal from the sensor?

Do the spikes occur randomly?
 
First, this is the actual signal. I only have an old analog scope, so I have recorded it:



The signal itself looks quite fine.

Spikes seem to occur just after another pulse, like seen below in green:

1634983479779.png

They result in spikes like these ones:
IMG_5838.PNG
I could filter those out in software but would prefer to have it all done in hardware.
 
Still trying to get the trigger perfect and start to suspect the VR conditioner itself is malfunctioning. So let`s get another one of those. The VR conditioner converts a signal as shown below into logical 1`s and 0`s. When a wave goes through 0, that point triggers the logical 1, once it goes back up and crosses 0, the signal is back to 0 again. To filter out noise, it measures the height of a wave and sets the new threshold at 1/3rd of that wave to rule out any noise. Perhaps that system doesn't work as it should for me.

1635441219117.png

During my test drive I blipped the throttle slightly on the roundabout which resulted in the back wheel losing grip. That`s one thing I`m still getting used to, you have _instant_ power with fuel injection. :D
 
If the noise spikes are at lower voltage than signal, then take a look at the ms vr conditioner.... which sounds similar to what you describe above.

https://www.diyautotune.com/support/tech/other/megasquirt-vr/
Circuit diagram
http://www.jbperf.com/dual_VR/dual_VR_v1_0_sch.JPG

Thank you for your help, it`s indeed similar although the VR conditioner from the speeduino has no hysteresis settings, it does it autimatically. However in this case, it might actually be too smart and it cannot work with just the six lobes on the flywheel, especially since one is much wider. I`ve searched but it`s hard to still find one of the old megasquirt VR conditioners to test this. The MAX9926 could be reconfigured to for instance remove the adaptive threshold but that requires a change on the circuit board itself.

As always, to be continued :)
 
During my test drive I blipped the throttle slightly on the roundabout which resulted in the back wheel losing grip. That`s one thing I`m still getting used to, you have _instant_ power with fuel injection. :D
My riding habits, I try not to do things abruptly. If I was going to 'blip a throttle,' it would probably be with the clutch pulled-in, to match engine and road speed.

Those MI Hooligans who prefer exhibitions of speed like the rolling-burnouts, are familiar with the effects of sudden changes in throttle. 😲

Those of us who are familiar with the way things were, particularly in roadracing, going back to the introduction of the transverse-mounted Japanese inline-fours, and at about the same time, the rise of the two-stroke Grand Prix bikes, how difficult it was to safely operate them, and to maintain control.

There were all-sorts of dynamics, from weak frames which didn't maintain their geometry due to the power of the bikes, a failure to use better materials, and just wrong positioning of the engine relative to properly-weighting the front end for reliable steering. Mike Hailwood incurred the wrath of Mr. Honda when he took the multi-cylinder Honda he was racing (and hating) and delivered it to a chassis builder in the UK, commissioning a bespoke chassis, using materials and geometry known to that chassis craftsman and his crew. Handling was much better! Hailwood's hand blisters subsided, the bike was easier to control, you can imagine what happened with his race results. Unfortunately, Honda decided to concentrate its efforts in automobile racing, F1, and their motorcycle GP efforts were abandoned by the factory. Read how the Ken Sprayson engineered frame was constructed for the Honda RC181: Honda RC181: Mike Hailwood’s “could-have-been” world-beater - Motorcycle Classics | Exciting and evocative articles and photographs of the most brilliant, unusual and popular motorcycles ever made!

Then there was the seemingly never-ending quest for 'more power,' with narrow powerbands, and explosive increases as they 'came-on the pipe.' 'Fast Freddie' Spencer won multiple championships because he apparently could sense when the bike was going out of control, and bring it back from that moment, time (and corner) and time again.

Anyone who's spent time with two-strokes knows, "it always runs so-good (just-before it seizes!)" Some riders knew better than their peers, how to sense the impending seizure, and rein in the bike, to prevent it. Kevin Cameron has written about this phenomenon, and of the handful of people who could do it continually. The Gift of Speed | Cycle World | DECEMBER 2005
 
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Time for an update :). Since it`s now bad weather I stared to disassemble the bike. The sync is still not 100% but need to pick that up in spring. So for now it`s time to rework the setup a bit. Since the original manifolds didn't work, I asked here about the optimal construction for custom manifolds and got the tapered answer from 02GF74 so I`m working with that.

First, I had a look at the current throttle body stack to see if I could create some from aluminum piping:

31.jpg

But since it`s curved, tapered and oval, it`s very hard to recreate that. Another cool thing though about creating something like this today instead of 10 years ago is the possibility of 3d printing. So I spent some evenings learning Fusion 360 and created the first model of what i`m looking for:



Cool isn't it? A friend of mine will print it with some low quality filament to see if all the measurements were correct, and from that he can print four that are of high quality. The bar in front is to attach the chrome shields, the 'block' in the side to screw the four stacks together. Likely another one of these blocks is needed on the correct side. Also, it now still has four base plate screws to test fit. Two intake manifolds use the top-left bottom-right screws, while to others use the top-right bottom-left screws.

To be continued :)
 
Odd you say it's not really working. Your base setup looks a good deal similar to the one on offer from Star Rider Performance. His is a machined piece while yours are throttle bodies bolted together, but the premise seems the same:

1638275276393.png
 
Odd you say it's not really working. Your base setup looks a good deal similar to the one on offer from Star Rider Performance. His is a machined piece while yours are throttle bodies bolted together, but the premise seems the same:

View attachment 81523

Hi Parminio,

I didn't say the throttle bodies aren't working, those performed way above my expectation, only little tweaking is required during winter time on some small details. It`s the Vboost original manifolds that didn't work. Cool picture though!
 
I don't pretend to be an expert on gas flow but wouldn't it be better to make it a continuous curve from gas entry to exit?
Less likely to cause turbulence?

32.jpg

Good point! Since my fusion skills now allow me to create curved stacks I updated based on your suggestion. Also, since the 3d printer cannot print anything with a 45+ angle, some supports were added. The 'shark fin' will be used to connect two manifolds (left-front to left-rear, right-front to right-rear) together. I`m not worried about side-to-side forces, but downward forces might stress the bolts on the cylinder head. This way, a pair of them support each other.

Let`s get this one printed :)
 
I am sure this has been covered, but why not use this setup?

https://roadstercycle.com/yamaha_vmax_fuel_injector_cv_car.htm

The first reason is that the guy never replied to my questions. In the end, I`m happy he didn't because I like my setup now much more :).
Second, it`s hard to use the original carbs since they have a small diameter and timing the injectors with vboost is very hard. The carbs deliver the correct amount of fuel due to the venturi-effect, but if you twist the trottle quickly and at the same time reach the RPM where the Vboost opens, it`s very hard to get everything perfect with injectors that depend on a calculated fuel load based on MAP and TPS.
Thirdly, the injectors should be below the butterfly valve, in that setup they are above.
 

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