How hot would the ignition end of the crank get on air cooled engines?

I know the head can get 300-500 degrees on some bikes, that oil can easily get to 300⁰F on an air cooled bike. I even know the rearward side of the engine by the transmission can get too hot to touch (learned that by accident), but I am curious if anyone has measured or has an approximate temperature the points area can get to.

Contemplating a EFI set up using a magnetic hall sensor as a side project. But the biggest issue would be finding an AlNiCo magnet or getting a neodymium to survive prolonged temperature exposure.

Ask your self, how hot would get the altenator rotor and his magnets covered in hot engine oil mist?
The ignition end of the crank is much "cooler" and the heat didn´t harm any electronic componets.


 

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Ask your self, how hot would get the altenator rotor and his magnets covered in hot engine oil mist?
The ignition end of the crank is much "cooler" and the heat didn´t harm any electronic componets.
 

Well alternators are designed for the heat they generate, majority of which have cooling fans (either internal or external) to help with the excessive heat build up.

Another note is usually the ignition side is the dry side, so no oil "mist" as long as you don't have a leaking seal. So I wouldn't have to worry about heated oil contaminating things (otherwise the points would foul in a matter of minutes and the bike would cease to run at all).

I am aware the ignition side is going to be cooler in respect to the engine overall, due to the zero "active" work on that side, but they will still heat up via convection, and even factory CDI pick ups are designed with heat tolerance in mind. I'm talking about adapting something that would normally stay rather cool, maybe 100⁰F tops, and adapting it to an area that likely exceed that within the first few minutes of starting. I just don't know if that side heats up to the 176 ish degrees Fahrenheit where neodymium starts to lose magnetism, which is quite low is respect of the potential 300⁰F an air cooled engine can get to (or even exceed) or if I would have to find a smaller AlNiCo magnet (which are good to 400-500⁰C) since most are closer to the inch diameter than they are to the quarter to three-eighths diameter I would be wanting for this set up.

I just don't have access to a IR thermometer, otherwise I would just check myself. LOL

If you search on here "oil cooler temperatures OMR" there is a chart Old Man Rock made recording various engine area temperatures before adding a oil cooler and after adding a oil cooler. I think his points cover temp without a oil cooler was about 140F, but there was no mention of the crank end temp.

Why would you be adding a magnet on the points side? Most guys who want to run a DFI conversion use a missing tooth trigger wheel and a Hall sensor (no need for a magnet) If you were going to mount a hall sensor under the stock points cover it would be further isolated from heat by a "L" mounting bracket. Cherry brand hall sensors are rated to 260F.

The Dyna S system has a magnet in those rotors = zero heat issues, so does the Kawasaki OEM version. Maybe those magnets are different?

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Why would you be adding a magnet on the points side? Most guys who want to run a DFI conversion use a missing tooth trigger wheel and a Hall sensor (no need for a magnet) If you were going to mount a hall sensor under the stock points cover it would be further isolated from heat by a "L" mounting bracket.

 Maybe those magnets are different?

who said I want to run DFI? The amount of modification for that is insane, pretty much needing a custom machine cylinder head (DFI = direct fuel injection, i.e. sprayed directly into the cylinder). I would be running essentially a TBI system, where the injector is on the throttle body right after the throttle plate.

As for the magnet vs missing tooth trigger. They both do the same job, but it's a lot easier to put a shaft collar clamp on the dry side with a magnet inserted and JB welded. There are hall sensors that trigger via magnetism. It'd also be a LOT cheaper and a lot easier to service, since you don't have to pull and machine your flywheel or have one fabricated.

Stock pulsing coils are likely AlNiCo, but cannot confirm.

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who said I want to run DFI?

I'm guessing Digital Fuel Injection is what Injected was getting at, which sounds like exactly what you're looking in to.

 it's a lot easier to put a shaft collar clamp on the dry side with a magnet inserted and JB welded. There are hall sensors that trigger via magnetism. 

You have exactly described the Dyna S trigger plate and rotor.  There is no reason to invent your own.  These have been in production for decades and they are easy to find new or used.

www.dynaonline.com/dyna-s

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wrote:

who said I want to run DFI?

I'm guessing Digital Fuel Injection is what Injected was getting at, which sounds like exactly what you're looking in to.

 it's a lot easier to put a shaft collar clamp on the dry side with a magnet inserted and JB welded. There are hall sensors that trigger via magnetism. 

You have exactly described the Dyna S trigger plate and rotor.  There is no reason to invent your own.  These have been in production for decades and they are easy to find new or used.

www.dynaonline.com/dyna-s

where I come from, DFI means "direct fuel injection", especially in the modern world where everything other than motorcycles has gone that route. 

And I am aware of the dyna s system, but they either never actually made a kit for a KZ400 or they don't anymore. I can find stuff for all the other bikes 550/650/750/900/1000/etc, of which the 550-750 "fits" with some modifications. Also, we're talking spending $200+, even used, for a component that I am LITERALLY only going to be using the pulse coil pick-up/generator off of. It'd be easier to just get a shaft collar, drill a whole and and JB weld a magnet in place and use a magnetic hall sensor where the hardest part is going to be fabbing the L bracket, which is fairly simple.

$30-50 vs $200+ for literally just the trigger mechanism for the system.

I would just install a KZ440 CDI system since it's essentially a direct fit, but even those parts are virtually impossible to find and when you do find them, you're still talking big bucks for just the pulsing coil / pickup coil / whatever else it may be called.

EFI = Electronic Fuel Injection
DFI = Digital Fuel Injection
FSI = Fuel Stratified Injection = direct fuel injection
TFSI = Turbocharged Fuel Stratified Injection = direct fuel injection

Kawasaki's fuel injection was called DFI but is a computer controlled throttle bodied injection, that is why I used that terminology as most on here understand those terms. I bought my magnetized stainless toothed wheel out of the UK for about $50.

 

Cherry hall sensor with pull up resistor

 

Microsquirt ECU wired and attached to bottom of battery box

 

GPZ1100 = DFI

wrote:

EFI = Electronic Fuel Injection
DFI = Digital Fuel Injection
FSI = Fuel Stratified Injection = direct fuel injection
TFSI = Turbocharged Fuel Stratified Injection = direct fuel injection 

The acronyms could go on for ever
DPI = Dual port injection
MPI = Multi-point injection
CRI =Common rail injection  
However can I point out that irrespective of wether you have points, CDI/TCI (oh no here we go again with the acronyms!) that the wiring for these is not heat wrapped like your stator windings so this would suggest the heat is not that great !! Also this set up all sounds very "hi-tech" but will "JB welding" a magnet to a collar on the end of the crank not upset the dynamic balance at 7000rpm ?

wrote:

wrote:

EFI = Electronic Fuel Injection
DFI = Digital Fuel Injection
FSI = Fuel Stratified Injection = direct fuel injection
TFSI = Turbocharged Fuel Stratified Injection = direct fuel injection 

The acronyms could go on for ever
DPI = Direct port injection
MPI = Multi-point injection
CRI =Common rail injection  

However can I point out that irrespective of wether you have points, CDI/TCI (oh no here we go again with the acronyms!) that the wiring for these is not heat wrapped like your stator windings so this would suggest the heat is not that great !! Also this set up all sounds very "hi-tech" but will "JB welding" a magnet to a collar on the end of the crank not upset the dynamic balance at 7000rpm ?

FGP =  Fu@#ing Good Post......