@Edward - This is simply a great project, I love this machine. It's nice to see we have ways of modifying this monster.
"I know a lot of Panhead owners who swear their motor starts on the first kick, which is probably true for the most part. But they will also tell you everything must be just right for it to come off on the first kick. I've also watched a few guys kick until they were blue in the face when things weren't just right."
Ohh yes not everyone knows the art of riding a Harley. As you said the rider need to know the correct technique and respect, this comes through experience.
I had a '67 BSA Thunderbolt w/ kick start. Nasty to start but always started on the last kick I had in me. After a couple of weeks I analized the process. I sat on the seat instead of standing on the starter, slowly rolled it and it started on the first time. Repeated from then on out. It was just playing with me.
Awesome idea and design! I'm going to build this ignition in a nose cone mounted variety for the Evolution motor. Maybe this will alleviate some of the hard starting issues with a high compression motor. The MSD brand single fire ignition that is installed now, is a big dissappointment. (Single fire refers to each cylinder spark firing individually. The factory ignition in an evolution motor fires both plugs at the same time, known as dual fire or wasted spark). The problem I am having is when the initial static timing is set for the best starting, the total advance, though adjustable to some degree, is too far advanced and causes pinging on most premium fuels. The range of adjustment isn't wide enough to keep the total advance manageable. The MSD ignition allows the use of a VOES (Vacuum Operated Electronic Switch) to control the ignition advance switching point using manifold vacuum. These switches are inherently finicky. When they work, they work good, when they don't work... The circuit as designed will allow me to control the advance without this switch. I should be able to tailor the ignition "map" to my motor's needs. Now all I need is an ICU with a USB port to be able to edit the ignition timing while running...
I have a stock '57 Panhead and I am interested in your devise. Being totally incapable of assembling your ignition control unit; how much could be for a complete set up provided by you? My old trick right knee has this retiree seeking your help. firstname.lastname@example.org
To answer the question about the original advance mechanisim in the Panhead, it was a twist grip on the left hand side of the handlebar which the rider could vary as desired. The epitomy of "tune by ear"... :)
Interesting design challenge to sync up with the motor within a single revolution.
Note that the actual timing requirements of the engine vary widely. Not only does it vary dependent on engine RPM but even more so by cylinder pressure and also by fuel mixture. Higher pressures burn faster and lower burn slower. Lean mixtures burn slower too. By way of example a classic Chevy V8 needs no more than 16* advance during cranking, 36* at full power/RPM, and 52* cruising. Due to the low cylinder pressure and lean mixture at idle optimum advance is up in the 40's but many mechanical setups cannot get there. An electronic mapping system with both RPM and MAP inputs can go a long way to optimizing the operation and efficiency of an engine.
Airplane ignitions have long had starting retard systems and so have some motorcycles.
Anyone interested in an extreme gadget here should investigate the Mega Squirt EFI system. An entire system build to facilitate expirementation and learning of how these things work.
Thanks for the comment. This ICU is not an ECU as it does not close the control loop with engine parameters other than RPM. It is strictly a mapped advance curve based on RPM. I wrote a white paper on it and sent it to Design News but I'm not sure if they made it available. If anyone wants a copy of it or any other documentation, email me and I will send it to you. If you are really considering building one for yourself, I will be happy to help if I can.
One of my main goals in doing this project was to educate myself a little further in the engineering aspects of the combustion engine. It is a stepping stone for me to my next endeavor which is to build an ECU. I plan on starting with a single cylinder 4 cycle engine that has an electric starter and an accessable ignition system that can be readily replaced. I have laid out the data acquisition system with 23 parameters. Next is building a small engine dyno for testing. Once that is through I can start ressearching engines. I plan on trying Microchips MCU's first, but I have a feeling it will require more processing horsepower especially when I move to more cylinders. I will probably step up to Freescale's stuff.
This is indeed a neat gadget. But I did not see the actual circuit, which would have been quite interesting. Also a few more dtails in the photos would have been very welcome. My next bike will be a chopper, but I don't know what kind of engine it will have just yet. My last bike was OK to start, but the fuel mix settings were a screaming pain. When set for best power it would not start, when set for good starting it would not make power. Sold. Oh Well.
How about electronic fuel injection of a bike? Are the automotive injectors rugged enough for bike use?
When you can't adjust a variable venturi carb easily, it is almost always a case of the tapered needle being worn and needing replacement. The taper is supposed to be continuous, but it will wear the most near the bottom, causing the mixture to be way too lean if you try to set the idle mixture right. The needles are only a few bucks.
I already know it is probably a stupid question, but no one answered it. Why can't you have an electric start dirt bike? They have electric start mowers. I must be missing something. It sure would be nice to hit a button when you are stuck in a mud hole rather than trying to kick it. Been there done that...not fun!
I continue to be amazed at the innovation and creativity that gets released when engineers retire from large corporations. The fact you designed this as your own educational exercise is impressive. Some companies are bringing back "engineering freetime". A concept that most abandoned decades ago when MBAs could not measure its Earned Value each week. Imagine what you could have done if you had your own creative time to develop your own ideas before you retired! My hat is off to you, Ed, never stop creating.
That looks very interesting, but I'd be very concerned about the life expectancy of the device with it being mounted to the crankcase right next to the cylinder like that. That thing is gonna get hot and with it being sealed up inside that can/cover thing, it's not going to see much, if any airflow through there. A lot of those components on the circuit board probably aren't going to like getting that hot for long.
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