Honda CX 500 Forum banner

121 - 130 of 130 Posts

·
Registered
Joined
·
49 Posts
Discussion Starter · #121 · (Edited)
jigglypuff, I am finally getting back into my efi conversion. Have you figured out how to verify base timing? I dont know what to shoot a timing light at, espeicially in your case since you aren't using the stock vr sensors.
Also I have a copy of the stock timing map if you need some info on that. I will go out and console into my Ignitech and pull the curve if you want to start with that for you base timing.

I was going to just use my ignitech for timing, but I decided against it, since it can only reference TPS and RPM. It cannot adjust for load.
Yep, it's a tough problem, and I don't have a perfect solution for it. Short of removing the engine and removing the back cover, I couldn't think of a spot to use a timing light either. The best alternate I found is to pick up signals from the stock VR sensors, feed it into the following circuit to generate a smoothed signal (a slight modification of the previous inductive pickup circuit), and match the Microsquirt output to the VR signals.



I'm assuming the stock VR sensors are advanced 15° at crank/idle, and the Microsquirt is fixed at 15° during the timing process. I'm recycling this image from a previous post: here's a sample of what the "matched" timing signal should look like:



As opposed to the inductive pickup method, there are no green/blue overlaps. The signals are much cleaner and less prone to induced noise.

It's by no means perfect, but the bike is running pretty well so far from idle to ~3000 rpm. There's a noise issue in the hall sensor that's been plaguing tuning for the past week (among other things, though) and has kept me from revving higher.


If you're willing to share your base timing numbers, that would be marvelous. I'm currently using MS2/Extra base numbers, which look fairly safe to me.

 

·
Registered
Joined
·
49 Posts
Discussion Starter · #122 ·
Also just to update progress:

1) The LC-1 was still behaving very erratically. It turns out is may have been a connector issue, however I still opted to use a 14point7 Spartan Lambda Controller . See that little bulge near the butt of the connector? The circuit board is tucked away there. It's _so_ much easier to integrate and hasn't given me any problems yet.

2) The oil leak near the cam cover has been resolved and the trigger wheel has been loc-tited into place after setting timing per the above method. The radiator and fan have been reinstalled, so now I'll be able to run for longer than a couple minutes at a time.

3) Not that I can run long durations, though. I've switched over from the B&G code to MS2/Extra as it opens up Diagnostics and more settings in TunerStudio, however it loses RPM sync every few seconds (Sync Error # 2). I'm not sure if it's software or electrical related, but I'll be looking into both to see what's going on.

4) The wideband is reading A/F ~11.5 even at idle. The pulse widths are ~1.8ms and I can't seem to figure out how to shorten it. It may be that Warm-Up Enrichment is kicking in, however problem #3 is preventing the bike from hitting operating temperature. I'm hoping that's the case, otherwise I'll need to source some smaller injectors... maybe around 210cc's instead of 260's. Spark plugs are getting fouled at an alarming rate.
 

·
Registered
Joined
·
554 Posts
i just got an email back from ignitech. He told me the pinout is 2,3, and 5, on their db9 connector for serial transmission. I will build a cable and test it out tonight.
 

·
Registered
Joined
·
554 Posts
Here you go. Picture 3 is the ignition advance curve programmed on the Ignitech. Max advance is set at 37 degrees.
Also note in the bottom left, the base timing is set at 15 deg. This is the number of degrees that the VR sensor is out from TDC, according to the software manual. I am going to compare this to the factory advance curve. For some reason I remember the factory advance going into the 40 deg range.













 

·
Registered
Joined
·
554 Posts
Here are the factory Ignition settings and how to check the base timing. I am interpreting the FSM to mean that the VR sensor is triggered at 15 BTDC, not at 0 TDC like I previously thought.




 

·
Registered
Joined
·
49 Posts
Discussion Starter · #126 ·
Wow, awesome. Thank you! I've updated my ignition map a bit to better match the Ignitech.
 

·
Registered
Joined
·
1,521 Posts
Remember that since your timing is now indexed to the cam and not the crank any slop / slap in the cam chain will affect your ignition timing.
 

·
Registered
Joined
·
49 Posts
Discussion Starter · #128 ·
Time for the yearly update! (Notice a pattern?)

The bike runs! And much better than shown in the old video, too.

Last year ended on a sour note after I nearly burned out the fuel pump. The fuel return line was tee'd into the stock supply port, and in a nutshell the gas never had a chance to cool down, hence the overheating pump. The solution was to properly weld in a new fitting, which in turn compromised the paint. There were several other issues with the paint in general, so I opted to do a DIY paintjob, which in itself took me about 10 months at my working pace.

In a nutshell, it worked! The gas/pump/tank still gets warm, but can be touched by a bare hand. After a couple days of tuning (fonque, those images you provided were invaluable!), the bike idles and revs fairly well. The tune certainly isn't done yet, but the bike can be ridden! There are still several issues to clean up, though:

1) The integrated Arduino has been exceptionally unreliable. Last year it burned out again. I'll probably just go to a mechanical switch to turn on the fan (à la the electric fan conversions). For now I hot-wire and run the fan directly.

2) O/F ratio is tracking around ~12.0 across the board, which is much richer than the ~13.5 I'd like to see. I suspect the R6 injectors (260 cc/min) may be a tad too large for this application. I'll keep trying to tune it out, but at the same time will be looking for smaller injectors in the 200 cc/min range.

3) There are intermittent RPM dropouts caused by loss-of-sync with the trigger wheel. It's either a) the 48-4 tooth wheel is just too much for the system or b) the Allegro ATS627 behaves erratically at high temperatures (the issue appears many minutes after warm-up, and the sensor is in a pretty hot area). Overall, this problem is tolerable as it mostly pops up during deceleration, but I'd like to fully remedy it eventually.

4) Surprisingly, the battery is able to start things up without a problem (granted the headlight isn't installed right now), but I haven't checked to see if the stock stator can keep up with the power demands... I suspect there will be a stator upgrade in the near future.

5) Miscellaneous wiring clean-up, routing, fuel lines, etc. Nothing major, though.

6) Miscellaneous mechanical stuff not related to the EFI conversion. Prior to the conversion, the bike underwent quite a bit of body work that was never quite finished to my standards. In comparison to the EFI work, this'll be fairly minor.

The weather is currently dreary, but I will take pictures/video as soon as I can! I'll also update all the documentation and get the Megasquirt files posted when the tube gets more refinement. I really never intended for this to take 3 years, and tuning will be a never-ending task, but the bike really should be about 90% there this season.

For anyone else thinking about doing a similar conversion... murrayf's Mikuni kit probably is a better option, haha. The time/cost versus return probably isn't worth it to most (there were many times I felt like just scrapping the project for parts), so you'll really have to be dedicated (or more talented than me) to finish something like this in a timely manner...
 

·
Registered
Joined
·
1 Posts
I know this is an old thread, but do you perhabs have some maps/tables I can borrow for my project? 😁
 
121 - 130 of 130 Posts
Top