GL1100 with GL1200 LTD EFI conversion

[theailer]

Yeah, I’ll leave the welding to my uncle
But lo and behold, the porker is in:

IMG_2910.jpeg

[theailer]

Subframe welded, just some painting and rust protection left to do.

IMG_2920.jpeg

[theailer]

Seems hammerite is pretty darn close to the original color:

IMG_2921.jpeg

[theailer]

Cooling/engine shroud and crossbar was in the way of the air/fuel assy, so I had to remove some material from the shroud in order for it to clear the throttle position sensor. And I had to move the crossbar to sit between the shroud and frame and then lock it dock with additional nuts on the frame side.

Screenshot 2025-06-01 at 19.55.42.png

Also the air cleaner box will not fit at all, so I'ts now running an open filter setup =) with only the air cleaner box lid on top to keep it fastened down.

[theailer]

Had to remove a tiny bit of material from the right timing cover in order for the motor to fit. Either it is sitting a bit more to the front than the old one or it is a bit longer.
Took the old fuse and turn signal thingy mount and repurposed that into the ECU mount, will also put a new fuse/power distribution box(visible in the back ground) where the old fuse box was.

IMG_2940.jpeg

[theailer]

Try to cover your eyes to not see the total mess that the bike is at the moment
But she fires!
https://youtube.com/shorts/bbQfqzPypsY ... yBWporZ4Cv
The starter seems to not disengage fast enough, hoping it is just from sitting still for 20years or so.
Also very impressed with the idle, considering that I have no idle system other than the ECU that is controlling it via the ignition timing.

[Rednaxs60]

Excellent progress - don't apologize for the mess, part of the journey. Played your video several times. Starter is working as should. Idles nicely. What are your intentions with regard to idle air control. The passive 1200 FI model system works well.

If it wasn't' for the cost, the ECU you have or its big brother that can use two WBO2 sensors would be nice.

[theailer]

Thanks!
I do not have the components for the passive air idle system, I’m missing the valve itself. And it’s still early but it would seem the ECU handles it pretty good without an additional system.
Right now I have disabled closed loop control, but after the basic fueling I’ll enable it with both WBO2’s

[Rednaxs60]

Honda used the passive IAC system because Honda found on deceleration with the throttle plates closed, not enough combustion air was available making the engine do all sorts of interesting things, highly recommend using it. Have an IAC valve recommendation. Will find. The IAC valve doesn't do a lot, it's water temp controlled. You can use just about any thermostatic IAC valve that operates on 12 VDC - water connections are not necessary. If you can get the IAC system components, you won't need to use a stepper motor.

What is the fuelling profile - SD? Simplest and easiest to use.
Ignition timing at idle?
Can you post a picture of the timing and VE tables for us 1200 FI nerds?

Cheers

[theailer]

I'm starting with alpha n at the moment, but will try SD tomorrow. MAP does seem pretty stable.
I'm using your ignition table as well.
I've only got to idle for now so thats why only those areas are filled in, there is quite the discrepancy between the two cylinder banks. Table 1 is the right side and table 2 is the left side. Not sure why the difference is so big between the banks.

Screenshot 2025-06-09 at 22.05.06.png

[Rednaxs60]

Good afternoon. Can only mention my experience with SD for the 1200 engine. Alpha-N too much VE tuning and not required for a 1200, SD easier. VE at idle of 1000 RPM and approximately 60 kPa should be approximately 35.

Why two VE tables? Should only need one. Speeduino can use two VE tables but this is generally when a user wants more granularity at specific power(s), or to switch between SD and Alpha-n. Speeduino calls this a "blended" fuelling profile.

Are you doing sequential fuel and ignition? If so, ignition is straight forward, 1-3-2-4. Same with fuel. If there are differences with the O2 readings, you are using two O2 sensors, you can use individual fuel injector trim to calibrate the injectors if your ECU has this feature/function. This is fine tuning but should not be needed.

There are engine operating constraints that can impact on VE such as health of the engine such as compression. I wouldn't get hung up on the VE tables until after you use SD, and start some road trials. If your ECU has an ECU tuning feature where it will automatically update the ECU table(s), use it to start. Do three/four road trials and let the tuning software dial in the engine tune. Once initial tuning is done, disable and do fine tuning by changing individual cell values manually.

Ignition timing is the same. The table you are starting with is a good starting point. Once the VE table(s) are calibrated, calibrate the ignition timing table(s) using small increments. Remember that the faster the engine operates the less timing is required. Has to do with fuel burn such that the maximum fuel pulse occurs approximately 10 to 15 degrees STDC for optimal engine operation.

Once VE and ignition timing is calibrated, AFR table is next. Set a speed and Rpm range, check AFR reading and input this number in the AFR table. Repeat for all other speed/RPM ranges.

O2 sensors disable for initial tuning. Use AFR reading as a guide for VE calibration. Set up for open/closed loop when populating the AFR table.

Good progress to date, keep up the good work.

[theailer]

Running sequential fuel and ignition.
Reason for two tables is for tuning the motor banks separately. I had one table initially but when checking the readings from the two WBO2 sensors I had to use another table since one bank was really lean. The individual trim would be reasonable to use when it only differs part of a percent or the like. I have a too big difference, around 20% difference in fuel between the banks. Have to check for leaks and throttle body sync today, if the weather permits. And a compression test if the other stuff checks out.

Could it have something to do with the incoming fuel line is connected first to the left bank and ends at the right bank, maybe blockage in the fuel rail or something as well?
Perhaps I have to check pressure readings on different places on the fuel rails too.

[Rednaxs60]

I submit that most of us address symptoms and not the root cause for an issue. I have done this as well. Engine setup is essential for an EFI system. The 1200 CFI system is well detailed in the OEM Supplement. If the engine tune is indicating an issue, use the Supplement to determine if there is a maintenance item that can be done to possibly make a difference, then operate the engine to determine if something has changed. The engine tune should only be changed if required when a new component is installed.

Fuel pressure will be the same throughout the fuel rail. I wouldn't focus on this. I would definitely do a cylinder bank sync/balance. Your description indicates one bank doing more work than the other. You only need to use two vacuum gauges, but connect four. You will be able to see the difference in the cylinders on one side, gives an indication of which cylinder is in better condition and doing most of the work on the side in question. Only need one VE table. Honda recommends a max difference of 10%.

I have considered installing a second O2 sensor for the left cylinder bank. Apparently I can connect this sensor to Speeduino and monitor it with TS. The signal/reading would not be used for engine tuning. I would need to revert back to sequential fuel injection and use ICFT. I would use the same O2 sensor on both sides and use the one on the side that would be most beneficial for the engine tune.

Use some Quick Start - ether, to check for leaks. If there are leaks, engine RPM will increase. Have vacuum gauges connected as well.

Compression test would be good, but remember that this is an engine health issue. I would not be concerned unless you intend to rebuild the engine. My engine was at 90 PSI before I rebuilt it. Operated fairly well at that compression.

Are you using COP units for sequential ignition?

[theailer]

Emptied out the coolant and removed the timing belt covers because I suspected I had the belt on one tooth wrong, but it was at it's correct setting.

Got the difference down to roughly 6%, me being a dofus had set the timing to 10degrees at the T1 mark.......

Running two VE tables still since then I can adjust the left and right bank separately and check for issues before enabling the lambda control.

Got both sides a bit balanced using gauges but a bit hard since I still have not connected the throttle wire to the throttle on the handlebars. So need to revisit that as soon as my new wire nipple arrives.

Then it started acting real weird, going leaner and leaner on both sides and I could hear the fuel pump working harder and harder.
Spent a cool hour troubleshooting the pressure sensor and pump until I removed the gas cap and I heard the sucking of air and then the pump almost immediately settled down. Gas cap is new since last year but new stuff can still go bad I guess.

No cop units, but a "ignition package" with four coils and igniters with separate inputs for sequential control:
https://www.h2mracing.com/engine-parts- ... ch-p-11058

[Rednaxs60]

I have been pondering your setup and have some comments for consideration, or not.

Do not tune to AFR, this table is the last to be setup based on VE and ignition tables. Use the AFR readings as indicators only. Have the O2 sensors disabled for initial engine tuning, these sensors should not be enabled until you have solid well tuned VE and ignition timing tables, and the AFR table has been populated based on these VE and ignition timing tables.

Learning from the school of hard knocks, only need one VE table. If there is a discrepancy between cylinder banks, it's mostly a cylinder balance issue. You do not need to have the throttle cables connected to adjust cylinder bank balance.

I expect you are using the 1200 FI air chamber, if so, the cylinder balance screw is on the right side and as you adjust it, you will need to adjust the engine idle. If you are having issues balancing the cylinder banks, the fact that you do not have idle air control may be the issue. The 1200 FI engines need additional idle air when operating. This could also be the issue with fuelling.

Honda realized this during the GW design/development phase, hence the passive idle air control. Idle air control is needed for deceleration as well.

Disable, zero out all featured/functions not required for initial tuning such as idle advance settings, IAT retard, Cold advance. You'll be pleasantly surprised at how few features/functions are required for initial engine tuning. Once the VE and ignition tables are calibrated, then the AFR table, start incorporating other feature/functions one at a time.

It's easy to go down the proverbial "rabbit hole" and start to incorporate features/functions that you may think are contributing to an issue. I have done just that.

Sequential fuelling and ignition is a personal issue, not a lot to be gained during normal road operation. There will not be a lot or any fuel savings, more for emission standards. It is good to know that you have made sequential work.

Recommend sticking to the basics, a roughed in ignition timing table, calibrate the VE table so that the engine operates as good as possible. Next calibrate the spark table, changing the ignition timing settings one point at a time, remembering that as MAP is closer to atmospheric and the engine speed is increasing, less timing is needed, all abut the burn rate.

Look forward to watching your project develop and come to fruition.