xs11 EFI

[Jemison Richard]

Where did you get the HC11 for that price?  What is the clock speed?  Any
A/D capability?  How much digital I/O?  At $70 I'm curious.

The reason bike idle smoothly yet rev like crazy is engine size.  As the
engine (actually the cylinder volume versus valve area) gets larger, the
engine requires more cam duration, lift and (if normally aspirated) more
overlap to adequately fill the cylinder as the rpm goes up.  So given two
8000 rpm engines, one 1litre and 1  7-litre,  the 1litre engine will sit and
purr right along at idle while the 7 litre will hardly idle at all!  This is
assuming comparable HP per unit volume of course.

And no, I'm not even as far along as you are, though I've got the start of a
basic control algorithm and have about 1/3 of my current algorithm in the
form of a flow chart.  I have also done some calcs WRT processor / timing
considerations and requirements and have determined 3 PICs which have enough
horsepower to provide all the A/D, I/O and processor cycles for my
requirements at the maximum sampling rate I anticipate.  That isn't much but
you have to start somewhere.  Oh, and I've read practically everything on
this and the EFI332 mail lists and web pages, the public library, the state
library and the university library (oh and my companies tech library) on
sensors, control algorithms, PICs, computer control and electronic fuel
injection.

Rick

> -----Original Message-----
> From:	Chaasman at aol.com [SMTP:Chaasman at aol.com]
> Sent:	Thursday, December 03, 1998 6:07 PM
> To:	diy_efi at efi332.eng.ohio-state.edu
> Subject:	Re: xs11 EFI
> 
> In a message dated 12/2/98 9:35:35 PM Eastern Standard Time, 
> JemisonR at tce.com writes:
> 
> >  Hello.  I'm trying to efi a 4 cyl  inline  4 stroke motorcycle (Yamaha
> >  XS1100) and after talking with some very knowledgeable folks on this
> and
> the
> >  EFI332 lists I've settled to this solution myself.  I'm afraid I don't
> have
> >  any experience with the system yet but intend to implement basically
> what
> >  you're describing here. 
> 
> <snip>
> 
> >  I'm thinking of driving this system with a PIC device along with a
> driver /
> >  drivers to boost the output signal to the level required to fire the
> >  injectors.  At this point here are my variables:
> >  
> >  INPUTS:
> >  	rpm 		digital	1
> >  	crank position	digital	2
> >  	TPS		analog	1
> >  	O2		analog	1	(at least for experimental
> >  development of the maps)
> >  	timers		digital	3	(count down timers to time event
> >  durations)
> >  	keypad		digital	3	(1 key for mode (startup, idle,
> >  normal, WOT), 2 keys for increase (+) or decrease (-) )
> >  
> >  OUTPUT:
> >  	injector fire signals	digital	2
> >  	 	
> >  
> >  These ideas are in their very early stages of development but this is
> my
> >  thinking at this point.  Let me know what you (or others on the list)
> think.
> >  That's why I'm here.
> 
> 
> I'm also EFI ing a motorcycle.  (I wonder how many other people on the
> list
> are)?
> 
> I'm starting with a GB500 (single, for simplicity) then moving on to my
> FJ100,
> then maybe a small-block chevy.
> 
> I looked at PIC's, but found an inexpensive (compared to the PIC) "starter
> kit" for the HC11.  For about $70 I got an HC11 demo board with enough I/O
> to
> do what you describe, and on-chip EEPROM to make code changes a snap with
> the
> supplied serial cable and download software.  It looks like I'll be using
> this
> thing to play with for now....have you considered the HC11?  If so why did
> you
> choose the PIC?  just curious.
> 
> Based on what I've heard on this list about (relatively) large cams and o2
> sensors, maybe a MAP input would be useful for tuning the idle mixture?  I
> would think bikes would have an agressive cam for the higher redlines, but
> they seem to idle smooth.  Maybe this won't be a problem for us bikers.
> 
> I'm not very far along yet...just lighting LED's.  How about you?
>