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Discussion Starter · #1 ·
Long time lurker here -- I won't go into my rationale for going EFI, and will be using this thread as a worklog to both inspire and receive feedback. Let's get started!



Helpful Links I've Found:

http://www.fzrarchives.com/ipb/index.php?showtopic=57207

http://www.smcomp.com/~smurph/RZ-EFI/index.html





Throttle Bodies:

Throttle bodies and injectors are from an 05 Yamaha R6 with 38mm bores. I meant to get the previous generation TB's with 36mm bores, but oh well. Splitting them apart and modifying them to fit seems pretty simple so far.







Spacers were sized so that the stock CX500 boots can be used, although the boot diameter is too small. That was solved by sanding down the stock boot and slipping a 2" ID fuel filler hose over.







And with plenty of hose clamps, fitment looks pretty close to stock.









 

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Discussion Starter · #2 ·
Fuel/Ignition Triggering

The goal at the moment is to figure out the fuel system first, followed by ignition. Based on research, finding a signal for fuel can be done using the stock stator VR sensors, however ignition gets kinda tricky. I couldn't find a straight reference as to whether the stock VR sensors will be adequate, so in preparations of future upgrades I'm looking to install a 60-2 trigger and 2 Hall sensors (spaced 80* apart) behind the radiator fan on the cam drive (an electrics fan install will be needed, naturally). There seems to be adequate room, and the concept is coming along. I'm hoping to start prototyping some parts later next week. The sensors will be DIY Allegro 627's:

http://www.msextra.com/forums/viewtopic.php?f=131&t=41370







 

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Definitely an intense project you have embarked upon..



don't forget to do up that right hand inlet stub top bolt.....



are you still going to use your tacho ??



good luck with it all
 
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Have to love it.



There are some of us over here working on Mega/Microsquirt EFI.



I'm sure your escapade will be grossly attended to.
 

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FWIW-

None of the aftermarket EFI systems deal well with two cam sensors. And considering the cam runs 1/2 the crank speed, two sensors at 80 means 40 degrees of crank revolution... 160 between cam sensors is more approtiate.



Keep in mind, as well, that cam chain slack and slap will affect the cam position sensors you are proposing to use.
 

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60-2 is overkill as well.



At best, you have absolute resolution of 6 degrees for each tooth (3 if the teeth are symmetrical and you count rising and falling edges).

That is not much better than the 10 degree resolution of a 36-1 wheel (5 if you sample rising and falling).



However, the higher tooth count means the EMS is working harder to calculate things and is more likely to miss events at high crank revolutions.
 

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Discussion Starter · #8 ·
Definitely an intense project you have embarked upon..don't forget to do up that right hand inlet stub top bolt.....are you still going to use your tacho ??good luck with it all
I've got a mechanical tachometer and will be keeping it installed.



Have to love it.There are some of us over here working on Mega/Microsquirt EFI.I'm sure your escapade will be grossly attended to.
Yep, I've been following your and Fonque's threads.
 

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Discussion Starter · #9 ·
when the throttle bodies pop off from a backfire i can make you us a set of intakes with 38mm mikuni spigots on themthat will hold them properly DAMHIK
Hmm, didn't expect that to be a problem. I'll keep your intakes in mind.





FWIW-None of the aftermarket EFI systems deal well with two cam sensors. And considering the cam runs 1/2 the crank speed, two sensors at 80 means 40 degrees of crank revolution... 160 between cam sensors is more approtiate.Keep in mind, as well, that cam chain slack and slap will affect the cam position sensors you are proposing to use.
Thanks for catching that calculation. I figured there might be some slack and error due to the chains, but I'll take the risk for now. I haven't dug under the crank covers yet, but it just seems so much easier to fit something behind the fan.
 

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All I can tell you is what my turbo'd EFI system senses. I do not have a mech fan driven of the cam.

I DO have two cam sensors mounted at the rear of the engine, by the water pump, to tell the ECU when a piston is at TDC on compression stroke so it can fire the correct injector.



IMHO, triggering ignition off the cam is a big NO-NO due to chain slack and slap... can be >1 degree crank rotation, which could amount to more than 3 at the crank.

But it's your bird, so fly it.




The 1st/last mega/micro squirt attempt ended up with changing the flywheel in order to get stable triggers.



/me watches with interest.
 

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Discussion Starter · #11 ·
60-2 is overkill as well.



At best, you have absolute resolution of 6 degrees for each tooth (3 if the teeth are symmetrical and you count rising and falling edges).

That is not much better than the 10 degree resolution of a 36-1 wheel (5 if you sample rising and falling).



However, the higher tooth count means the EMS is working harder to calculate things and is more likely to miss events at high crank revolutions.
Since it's on the cam, isn't the effective resolution (relative to a crank sensor) 12* and 20*, respectively?



The Allegro 627 is rated up to 12,000rpm with a 60-2 wheel. I'm base-lining the Microsquirt for the EMS... in a nutshell, it had better be able to handle that sort of computational load.
 

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Whatever sensor you are using, (at least) double the error rate when using it on the cam as opposed to crank sensing since the crank is travelling double the cam the speed.
 

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And I don't know about +12 and +20....



the flywheel I have, has the "trigger" at around 25 BTDC, which means I get two crank triggers on a cylinder before I get a cam trigger
 

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If all you are doing is fuel injection, I wouldn't worry much about the error.



If you are trying to trigger sparkplugs... 1-3 degrees can make a HUGE difference.
 

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How about this?



1. Make a cup for the primary drive crank gear bolt, on the front of the engine. Grind down the flange on the bolt, slightly, to fit inside the cup. Make a seal carrier out of the plug that covers the bolt, the outside of the cup runs in the seal. Tabs on the cup to carry your trigger wheel that runs your efi. External mount the pickups.



2. Run stock ignition on the other end of the crankshaft.



I dont know your system. Hopefully, the system you are working with will be relatively simple,compared to newest technology. We are looking forward to your results!



Thanks, JimL
 

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Sorry about the confusion....I think I figured out it is not a complex package.



As they used to say on SNL...."never mind."



Regards, JimL (old easily confused guy)
 

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awesome i anticipate the results : D
 

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Sorry about the confusion....I think I figured out it is not a complex package.



As they used to say on SNL...."never mind."



Regards, JimL (old easily confused guy)


Rosanna Rosannadanna,

[media]http://www.youtube.com/watch?v=V3FnpaWQJO0[/media]
 
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