Author Topic: Fuel injection retrofit  (Read 30536 times)

Offline connie_rider

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Re: Fuel injection retrofit
« Reply #180 on: December 26, 2018, 07:37:19 AM »
Your speaking a language I don't understand, so I'm not even sure I know what you said.
But it sounds like your ready to do a test ride, and be able to tune on the go...
Yahooooooooooo

Ride safe, Ted

gpineau

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Re: Fuel injection retrofit
« Reply #181 on: January 12, 2019, 02:40:41 AM »
For the past week I have been fighting an intermittent problem where the RPM drops to zero then spikes to 4k causing the ECU to loose sync. It turned out to be noise being generated from the fuel pump getting into the ECU power and required some rewiring to resolve. Just one more ghost that needed busted.

From the beginning I knew it was going to be a steep learning curve but I never would have thought it was going to be as involved as it has become.  I have made a lot of mistakes. I’ve pursued some ideas that turned into dead ends and had to find alternatives.

The scope of what was necessary to get this bike running is much more than I expected. The removing of the flywheel and drilling teeth every 10 degrees was just about the limit of my skills and capabilities.  The expenses involved in purchasing materials and components only to throw them away when they served their purpose or didn't work out. I have also purchases specialized tools that I may never use again.  I don’t expect that anyone would want to go through the trouble that I have to replicate what I have done.
 
 Today was cold and raining but I ventured out anyway.  The bike has a rough idle and wants to stall at stop signs. Off idle it runs well with good throttle response.  I went out on the back road. It has plenty of power.  I rode it a couple of miles.  It's 30 years old. The tires are bald and won’t hold air overnight and it hemorrhages oil while it is running.  It sputtered to its final resting place under its own power. This old bike has served as a learning experience and I’ve learned a lot.
 
Things I have learned.

You must have crank position information for the ECU.   Without position information it will run but it won’t run well. And most certainly you can not control ignition without crank position information.

There is a time lag between the ECU fuel adjustment and the O2 sensors feedback to the ECU.  The O2 sensor should be as close to the exhaust port as possible. (thanks MOB)
 
ABS plastic will not hold up to gasoline for a long time. It gets soft and spongy.
 
JB Weld is great stuff. It will solve most attachment and plumbing problem quickly but even JB Weld is temporary.

High pressure fuel lines must be securely clamped. Preferably with screw clamps on barbed fittings.
 
Fuel pumps generate a lot of electrical noise. They can cause all sorts of strange intermittent problems. They should be connected to the battery through a relay. They should not share the same power line as the ECU.
 
Temperature sensors are critical to fuel injection and you must know their specs or be able to calibrate them. Use only parts that you know the specifications of or have the ability to characterize them.

Know the specifications of the fuel injectors you are using or have the capability to characterize them. You can’t guess at it. Open delay and Injector performance will vary with battery voltage.

Engines need air at idle. A closed throttle body will suffocate an engine. You need to bypass the throttle plate with a little air at idle.

Poor crimps and loose connections will haunt you. Use quality connectors. Crimp and solder all connections.  Use the correct connector for the application.

I got a lot of good advice from this forum. Thanks for that. 
I am not calling this a success I am calling an experiment that turned our well.  I have begun salvaging parts for my next project. 
I have some better ideas for doing a better job next time.

Offline Freddy

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Re: Fuel injection retrofit
« Reply #182 on: January 12, 2019, 07:04:51 AM »
I just re-read your first post.   :goodpost:  12 out of 10 for persistence and innovation.   
The best substitute for brains is .............what?

Offline gPink

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Re: Fuel injection retrofit
« Reply #183 on: January 12, 2019, 09:54:34 AM »
Thanks for posting. Come back with your next project.

Offline connie_rider

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Re: Fuel injection retrofit
« Reply #184 on: January 12, 2019, 10:35:49 AM »
Thanks for the final report.
What is the next project?

Ride safe, Ted

gpineau

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Re: Fuel injection retrofit
« Reply #185 on: January 12, 2019, 12:10:52 PM »
The entire saga including the final tune.
https://www.youtube.com/playlist?list=PL9ZAieLe6zonSleaj5i7FP0fbTPn_Uqb9

I still have a Connie and a lot of ideas. ......i'll be back.