Topic: EFI

[smccloud]

I know HondaMan was working on an EFI setup for the CB750 but I forgot about it until I found this on YouTube.  Anyone have more information on a decent way to do said conversion?

http://www.stuntlife.com/forums/164-general-sportbike-discussion/215276-megabike-carb-efi-conversion.html for more info.

[HondaMan]

Wow, several brains on it at once!

I gave them my two cents' worth, thanks for posting the link to their survey!

The biggest shortcoming I have seen so far in the "off the shelf" (sort of) kits is the lack of a viable accelerator pump simulation and poor control of the fuel during the waste-spark overlap cycle. The latter causes blued, then burned, pipes, because there is too much fuel coming through the head between cycles. This is caused by having just one injector, like a throttle body, or by having all injectors fire at once, like the Kawasaki 1000 bikes. They had very expensive pipes to mitigate the bluing effect, and we don't have that option.

So, I told the ambitious college kids to please consider that in their design! Hope they do...

[smccloud]

Wow, several brains on it at once!

I gave them my two cents' worth, thanks for posting the link to their survey!

The biggest shortcoming I have seen so far in the "off the shelf" (sort of) kits is the lack of a viable accelerator pump simulation and poor control of the fuel during the waste-spark overlap cycle. The latter causes blued, then burned, pipes, because there is too much fuel coming through the head between cycles. This is caused by having just one injector, like a throttle body, or by having all injectors fire at once, like the Kawasaki 1000 bikes. They had very expensive pipes to mitigate the bluing effect, and we don't have that option.

So, I told the ambitious college kids to please consider that in their design! Hope they do...

Check out http://microsquirt.info
It looks like it might be just what is needed for us to get EFI on our CBs.

[fuzzybutt]

http://forums.sohc4.net/index.php?topic=30624.0

[KingCustomCycles.com]

I am certain this can be done.  I have some training and experience in aircraft systems and have worked on them for 25 years.  If the pronlem is solved though, what will we all do during the time saved not cleaning and adjusting our carbs and the rest of the time sharing that information with others?  I am too old to find another hobby this fun.   

[smccloud]

I am certain this can be done.  I have some training and experience in aircraft systems and have worked on them for 25 years.  If the pronlem is solved though, what will we all do during the time saved not cleaning and adjusting our carbs and the rest of the time sharing that information with others?  I am too old to find another hobby this fun.   

out riding?  and i'll be greatful to not try to stick a carb needle through my finger while trying to re-assemble them.

[Soos]

If I had the $$, time and a few 750's to test things on.
Nice to see people out there getting something going at least.
Mabey someone will catch on and start selling kits on e-bay or something.





l8r

[MRieck]

Wow, several brains on it at once!

I gave them my two cents' worth, thanks for posting the link to their survey!

The biggest shortcoming I have seen so far in the "off the shelf" (sort of) kits is the lack of a viable accelerator pump simulation and poor control of the fuel during the waste-spark overlap cycle. The latter causes blued, then burned, pipes, because there is too much fuel coming through the head between cycles. This is caused by having just one injector, like a throttle body, or by having all injectors fire at once, like the Kawasaki 1000 bikes. They had very expensive pipes to mitigate the bluing effect, and we don't have that option.

So, I told the ambitious college kids to please consider that in their design! Hope they do...

ECU's are so powerful now sequential injector firing/duration is no problem. The fuel map is just the beginning as timing/spark parameters can be tightly controlled too allowing for higher CR with no pinging. Tuning is great as you can put it on a dyno and measure A/F. New bike ( i.e. 2002 to 2008 Hayabusa) ECU's can easily be reflashed....there is a ton of adjustability built into them from the factory.

[smccloud]

If I had the $$, time and a few 750's to test things on.
Nice to see people out there getting something going at least.
Mabey someone will catch on and start selling kits on e-bay or something.

l8r

actually, if i can get it to work with my hondman ignition box i was thinking of seeing if he wanted to team up and come up with a kit

ECU's are so powerful now sequential injector firing/duration is no problem. The fuel map is just the beginning as timing/spark parameters can be tightly controlled too allowing for higher CR with no pinging. Tuning is great as you can put it on a dyno and measure A/F. New bike ( i.e. 2002 to 2008 Hayabusa) ECU's can easily be reflashed....there is a ton of adjustability built into them from the factory.

the microsquirt actually allows pretty much everything you said.  the lack of a bike dyno in the area (that i know of) will the the hardest part for me

[jonbuoy]

I can see why people want to do this on dragbikes/turbo'd bikes but it would look butt ugly on a CB750.  Triumph go to a lot of trouble to make throttle bodies look like carbs on the retro models
. 

[dusterdude]

one of our forum mates has been messing with fi for a right good while on his bike,problem is i cant remember who it is.

[KingCustomCycles.com]

If cosmetics is the only barrier, I can fab them to look like anything you like.  It is a long story starting with fiberglass and balsa wood about 36 years ago.

[smccloud]

I can see why people want to do this on dragbikes/turbo'd bikes but it would look butt ugly on a CB750.  Triumph go to a lot of trouble to make throttle bodies look like carbs on the retro models
. 

it looking ugly is personal opinion.  personaly i'd like the "high tech" look.  i'd really like the fact that my bike would run a lot better.  plus it paves the way for me to add a turbo later on

[my78k]

This thread Duster??? It was 750essss

http://forums.sohc4.net/index.php?topic=30624.0

Dennis