EFI conversion on a Gen-1

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RempageR1

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Another update on the project: I`ve been driving with the V1200i last weekend and drove around 900KM. I had the carburetors and fuel pump with me as a backup but luckily I didn't have to use them :).

The system worked perfect, with one exception on the day I set off to drive home. Then, after 500m it stumbled and died. After turning the ignition off and on, and starting again it worked as it should. Although I didn't have the logging enabled at that time, it`s likely due to the rather poor signal I get from the crank. As shown before, I get two pulses one of which needs to be filtered out to make just one. This gives me just one pulse per rotation which is not ideal. Therefore I`m looking for a `91 or newer flywheel. This has six lobes so you get six pulses per rotation which is much better. If anyone has one laying around please let me know.

Then there`s the fuel map, which looks something like this:
1630088163957.png

Nothing strange, except over 80% throttle where it seems to require a huge amount of fuel around 3000 RPM, and then it requires way less around 4500 RPM. If I time how quickly the revs rise, the 100% TPS position is the quickest so something must be right. I`m unsure what happens with the fuel load though.

Another thing is the Vboost. Since the throttle bodies have a way larger diameter, the VBoost is only noticeable with the throttle on 40% or less. So effectively there is little benefit of leaving it on. To address the fuel load 'strangeness' above and to perhaps give it more power, I will over winter create some new manifolds which are larger in diameter and without the Vboost.

Will update on the progress :)
 

VMAXXIMUM

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Another update on the project: I`ve been driving with the V1200i last weekend and drove around 900KM. I had the carburetors and fuel pump with me as a backup but luckily I didn't have to use them :).

The system worked perfect, with one exception on the day I set off to drive home. Then, after 500m it stumbled and died. After turning the ignition off and on, and starting again it worked as it should. Although I didn't have the logging enabled at that time, it`s likely due to the rather poor signal I get from the crank. As shown before, I get two pulses one of which needs to be filtered out to make just one. This gives me just one pulse per rotation which is not ideal. Therefore I`m looking for a `91 or newer flywheel. This has six lobes so you get six pulses per rotation which is much better. If anyone has one laying around please let me know.

Then there`s the fuel map, which looks something like this:
View attachment 79296

Nothing strange, except over 80% throttle where it seems to require a huge amount of fuel around 3000 RPM, and then it requires way less around 4500 RPM. If I time how quickly the revs rise, the 100% TPS position is the quickest so something must be right. I`m unsure what happens with the fuel load though.

Another thing is the Vboost. Since the throttle bodies have a way larger diameter, the VBoost is only noticeable with the throttle on 40% or less. So effectively there is little benefit of leaving it on. To address the fuel load 'strangeness' above and to perhaps give it more power, I will over winter create some new manifolds which are larger in diameter and without the Vboost.

Will update on the progress :)
Sean would probably be your best bet for the flywheel.
 

02GF74

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If you cannot source one, an option would be to weld on the projections, ensuring that they are diametrically opposite to keep the flywheel in balance. A square piece of steel with a hole plug welded on and you could measure up the exact position you want them.
 

WILLRIDEAGAIN

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Another update on the project: I`ve been driving with the V1200i last weekend and drove around 900KM. I had the carburetors and fuel pump with me as a backup but luckily I didn't have to use them :).

The system worked perfect, with one exception on the day I set off to drive home. Then, after 500m it stumbled and died. After turning the ignition off and on, and starting again it worked as it should. Although I didn't have the logging enabled at that time, it`s likely due to the rather poor signal I get from the crank. As shown before, I get two pulses one of which needs to be filtered out to make just one. This gives me just one pulse per rotation which is not ideal. Therefore I`m looking for a `91 or newer flywheel. This has six lobes so you get six pulses per rotation which is much better. If anyone has one laying around please let me know.

Then there`s the fuel map, which looks something like this:
View attachment 79296

Nothing strange, except over 80% throttle where it seems to require a huge amount of fuel around 3000 RPM, and then it requires way less around 4500 RPM. If I time how quickly the revs rise, the 100% TPS position is the quickest so something must be right. I`m unsure what happens with the fuel load though.

Another thing is the Vboost. Since the throttle bodies have a way larger diameter, the VBoost is only noticeable with the throttle on 40% or less. So effectively there is little benefit of leaving it on. To address the fuel load 'strangeness' above and to perhaps give it more power, I will over winter create some new manifolds which are larger in diameter and without the Vboost.

Will update on the progress :)
Keep up the good work 👍🏾
 

RempageR1

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Just a small update for today. Modifying the lobes on the old flywheel might work but I wonder how to balance it afterwards. Luckily, after doing some calls I found a good flywheel and pick-up.

And when it came in, it was time to program the Speeduino with the following pattern:
23.JPG

After some days of programming, it seems to work on the bench so the next step was trying to get it to work on the bike.

But before doing that, I had to reprogram the Ignitech with the config used for the 1990+ bike with one pick-up and install the new hardware:
24.jpg

After a job well done, I tried to start the bike tonight and it wouldn't start. After messing with some settings it ran very rough and backfired like crazy. Looking down into the throttle bodies to identify the backfiring cylinder might not be the best way to troubleshoot:
1631474606875.png

So I compared the wiring instructions for the Ignitech of the 85-89 (four pick-ups) with 90+ (one pick-up) and found out the Ignitech changed the wiring order for the HT coils for both models:
Orange wire: Old: Channel 1 New: Channel 2
Yellow wire: Old: Channel 3 New: Channel 4
Grey wire: Old: Channel 2 New: Channel 1
White wire: Old: Channel 4 New: Channel 3
Funny guys......

So after changing the firing timing in the config, all was well and it starts now with the new flywheel. Next up is testing (and likely) debugging the trigger in the Speeduino config so the Speeduino can work with the Vmax new flywheel.

To be continued....
 

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