EFI conversion on a Gen-1

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Hi!

It`s been a while so I thought it was time for an update. I`ve done a lot of work in the mean time and decided not to just move the injectors closer to the intake manifold, but to use two sets of injectors. The second set I got from a CBR 600 PC41.

The injectors close to the cylinder head will be used for more precise fuel delivery whilst the injectors that are inside the throttle bodies will be used when more power is required. An injector has a duty cycle, which is the time the injector is open during a full 720 degree revolution. 100% percent duty cycle therefore means open all the time. I want to use a duty cycle of 15% to start with so the injector will only be injecting fuel when the intake valve is open. Since I now run sequential, I know exactly when the valve is open. With that, you can setup the Speeduino to be done with injecting fuel at a certain time to ensure it`s all delivered before the valve closes.

If more fuel is needed that can be delivered within 15% duty cycle, the second set of injectors is added so all eight injectors fire. This is all done automatically by speeduino, you only need to know the exact flow rate for the injectors. To do that, I connected each of the injectors to the fuel line and had it spray into a coke bottle as shown below:



View attachment InjectorFlow.mov

I used a kitchen scale to measure the weight of the bottle (minus injector and wiring) and then turned the injector on for 30 seconds. The difference for the small injectors was 78 grams (with 1 gram deviation between them). The big ones (I already had) do 132 grams (also with 1 gram deviation between them). So the small ones` flow rate is 156 grams per minute, the big ones 264. Next step is to convert that to cc/mins and configure Tunerstudio.

I also worked on creating new manifolds, will provide an update about that shortly :).
 
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If 1 ml=0.68 gram gasoline then 156 grams/ .68 g = 229.41 ml as 1ml =1cc.

Then 229 ml = 60 seconds of fuel delivery for the smaller F.I.

264 grams / .68 grams = 388.24 ml

388 ml = 60 seconds of fuel delivery for the larger F.I.
 
If 1 ml=0.68 gram gasoline then 156 grams/ .68 g = 229.41 ml as 1ml =1cc.

Then 229 ml = 60 seconds of fuel delivery for the smaller F.I.

264 grams / .68 grams = 388.24 ml

388 ml = 60 seconds of fuel delivery for the larger F.I.
Thank you, I will use values close to those. In the Netherlands, we use fuel which has around 5% ethanol so I have account for that as well. Ethanol is heavier so my flow rates are slightly lower. It doesn't mattter that much however, the ratio between the two injectors is what mostly matters.

On to the manifolds then :). I spent a lot of time trying to figure out the best way to fit the smaller injectors. Since the cylinders are quite close to each other, it was a very tight squeeze to get them in. Also since the front cylinders are 5 cm or so to the right, the injectors would ideally be placed like this:

1703697244039.jpeg


The challenge with that is to fit a fuel rail. Since the injectors are so close to each other the only option would be to fit fuel line directly. But that would mean the fuel line for the left one would go around the manifold on the right looking horrible.

After a _lot_ of different test prints I decided to go for a setup where the injectors face eachother and both are tilted up 15 degrees from horizontal.

Some pictures:

1703697611772.jpeg

1703697527111.jpeg

To drill the holes correctly, I 3d printed a 'holding tool' where the aluminium block fits into. This has a 15% angle so you can drill straight down with a column drill:

1703697780272.png

This drilled a hole of 10.4 mm which I expanded to 10.6 with a reamer tool.

So well on my way with this round of updates, will keep you informed on the progess :)
 
Would diesel commonrail tubes be out of the picture? After all, it would not be very practical to have a fuel delivery system that requires one to take off the intake manifolds in order to be removed. What is your fuel delivery pressure?
 
There is about 7mm space between the two injectors so a T-shape connector is the only thing that fits. You should see it as a subassembly like the Vboost manifolds :). Fuel pressure is about 60 PSI.
 
A Tee connector with that space would be very difficult to install without hurting the o-rings. You were thinking of prying it on with least possible shoulder? How do you secure it in place, how do you secure no leak situation? How do you connect between the two Tees? How do you import fuel, how do you control the pressure?
 
A Tee connector with that space would be very difficult to install without hurting the o-rings. You were thinking of prying it on with least possible shoulder? How do you secure it in place, how do you secure no leak situation? How do you connect between the two Tees? How do you import fuel, how do you control the pressure?
That`s a lot of questions in 1 post :).

You first install both injectors into the aluminium t-connector, then add the manifolds and across the manifolds there will be two aluminum plates securing the two manifolds together. That will be the same style as you can see in previous posts.

The manifolds will reach all the way up to the aluminum t-connector as you can see here:

1703846279324.jpegIt all goes together pretty smooth. I already did a leak test and it works just fine that way. Fuel pressure is controlled by a regulator, you can find the details in this thread.
 
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This topic was due for an update for a long time now. Sometimes things in life do not go as planned, and for me that happend at the end of January this year. Had a snowboard accident on holiday in Germany and damaged my 12th vertebrae. That meant the mod-monkey in the hospital decided I needed some titanium upgrades:

1724953139218.png

After getting injured on Monday, and being operated on Tuesday, I was released from hospital on Friday. I could then walk with crutches, but was told I needed them for 2-6 weeks before I was able to walk without them. Five days later, I was walking without them again. God was looking after me.

Here in the Netherlands, one of the first questions I asked the surgeon: "When am I allowed to ride my bike again?". The answer was three months, which I tried but decided two was long enough :). After being bedridden and going into an operation that risked paralysis, going for that first ride was awesome. And the second, and the third.

Back op topic:

In those two months, I was able to finish the bike. Here`s a picture with all four stacks printed in Nylon-CF:

1724953623478.png

With the injectors now way closer to the cylinder head, the response is much quicker. So mission accomplished. The next thing on the list was the on/off response of the throttle. Since the manifolds are very big, just turning the throttle slightly resulted in the bike accellerating hard. So that could be better.

Over some iterations, I printed these asymetrical pulleys so the butterflies would open slightly at the beginning of the throttle and then open faster as the throttle is twisted more.

This is how it was:
1724954126596.png

And how it now moves:
View attachment IMG_8813.MOV

So that`s pretty much it :). Driving it and having fun. But this winter, perhaps I will add these throttle bodies:

View attachment IMG_8990.MOV

They feature two butterflies, one that is cable-operated (for safety) and a second one that can be controlled by the EFI controller. That way you can further tune gas response and also add different throttle mappings. How cool would that be? :)
 
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I think those pieces in you have serial numbers. Glad you didn't have lingering issues. Also glad you're OK to resume riding.

Many people would be interested in the cost to do their own installations.
 
Hi Fire-Medic,

This will always require someone to do the installation I`m afraid. I don't think most people have the skills to modify the gas tank, install all electronics, weld the bung for the O2 sensor and then create a tune specific for their bike. If someone in the US wants to start a business for converting these bikes I`d be happy to assist in any way I can.

Also, if someone feels they have the skills for all of this, I can provide for instance the printed manifolds and other bits to get them under way. I have so far provided one person with manifolds and helped another by creating a 3d model for the specific manifolds he needed. Unfortunately after delivery I never heard back from them so I`ve no idea if they succeeded with the conversion.

Currently working to see if I can get both sets of stepper motors exactly synchronized so I can control them with 1 stepper driver. Fun stuff :)
 
Hi Fire-Medic,

This will always require someone to do the installation I`m afraid. I don't think most people have the skills to modify the gas tank, install all electronics, weld the bung for the O2 sensor and then create a tune specific for their bike. If someone in the US wants to start a business for converting these bikes I`d be happy to assist in any way I can.

Also, if someone feels they have the skills for all of this, I can provide for instance the printed manifolds and other bits to get them under way. I have so far provided one person with manifolds and helped another by creating a 3d model for the specific manifolds he needed. Unfortunately after delivery I never heard back from them so I`ve no idea if they succeeded with the conversion.

Currently working to see if I can get both sets of stepper motors exactly synchronized so I can control them with 1 stepper driver. Fun stuff :)
This is a slick setup! Would like to get one in person and test it out. Might be able to help US riders (and others) get into the modern age with it all.
 
This is a slick setup! Would like to get one in person and test it out. Might be able to help US riders (and others) get into the modern age with it all.

Hi Sean,

I was thinking about this whilst going for a ride on the max. The ultimate goal would be to build a simple setup that keeps the bike as stock as possible and follow the KISS-principle.

What if the carbs remain in place and they act as throttle bodies, and the injectors are some way added to the manifolds, like in the place shown below:

1726514905153.png

Then you can get the MAP pressure from the MAP sensor currently in place for fuel load and get the RPM from the tach. A water temp sensor can be added to the hose on the top-right where the filler cap is. Air-intake temp is one hole to be drilled into the airbox.

Next, to eliminate the return line in the fuel tank, a PWM-type fuel pump can be used:
https://www.vaporworx.com/resources/fds/8-how-pwm-returnless-fuel-systems-work/

If a good base tune is created, the O2 is only needed for people running different exhausts etc. After a while, there should be a pool of tunes to choose from.

That would keep everyting pretty much stock, the carbs no longer get fuel but remain in place. You can even keep the Vboost system like that.

If people are genuinly interested in that, I can do some homework on feasiblity and costs. If it looks doable and need to buy parts, perhaps we can make a kickstart project out of it or so.

Just let me know.
 
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Between Kyles friend Max and what you have I would think a good system can be designed. The stock idea would be pretty slick and apply that KISS as you said. I can supply whatever parts are needed to test with or modify.
 
Between Kyles friend Max and what you have I would think a good system can be designed. The stock idea would be pretty slick and apply that KISS as you said. I can supply whatever parts are needed to test with or modify.
I think the step 1 would be to think about how to add the injector holes/housing to the current manifolds. If that can be done it would simplify everything. If not, I can create a Fusion360 model and 3d print it. And then later see if we can get it CNC`ed or so.

Any ideas on that?
 

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