Fuel Injected 1962 Honda CB77 Superhawk

The back is electrically insulated but designed to conduct heat to whatever you mount it to. That's to say it is designed to be mounted to some form of heat sink. I used a steel epoxy to mount the two halves. It's not JB weld, but a quick-dry formula I like from working on other projects. I know it's not very glamorous just epoxying the headlight to the copper, but it seems to work pretty well. The 180-crank 300cc vibration test will say if it is truly a workable solution!
Alright, haven't had a huge amount of time to work at this stuff, but I did get a couple steps done. First off, I got the bars on. This wasn't a difficult process, just involved a few more well-placed holes drilled without weakening the relatively thin steel. I routed the starter, horn, and high/low beam wires through the holes, down the bars themselves, out another small hole in a slightly less conspicuous spot by the triple clamp, and into the headlight case where they will meet up with the main harness and LED headlight. I found out that the JC Whitney/EMGO brake and clutch levers are based off the Honda CL/CB72/77, so they look exactly the same as my stock ones but shinier and with some condoms on the tips. The brake lever boss even has a little hole that, I assume, is for some front brake light switch. Now that would be a big improvement for this bike. I don't use the rear brake all that much, and it's a choice between setting the rear brake switch too high as to flicker or so low that you really have to be serious about stopping to trip it. Having a front brake light switch would be outstanding. Unfortunately, EMGO is out of Thailand or someplace and nobody was around to tell me what that part is supposed to be. All the easily available non-hydraulic brake light switches I found online were way too big to fit where I need it. I went to my electrical fallback: Radio Shack. They had some little momentary, normally-open switches that roughly fit in the little hole. I epoxied one in (I'm going to say 50% of this bike is now epoxy) with a little #4 nut on the end to reach the switch point. It works fine, if it's a bit ugly. I also had some time to install little thing like the longer shift rod after some clocking of the shaft. It looks a bit weird being that long and is kind of hard to use with that long shifter, but it should be fine for every day use. On the hydraulic steering damper front, I had to order the special angled bolt that replaces one of the front engine mounts. It is a whopping $75 (SEVENTY-FIVE DOLLARS!!!) since they are so rare. As stupid as that price is, it's kind of like gum at the airport, where you going to go for a better price?

The LED headlight went in to the bike with the correct wiring so I could test it all out in the proper application. It work pretty damn well. With the high beam on it uses about 15W, with the low beam on, it uses a measly 3W. That's 1/3 of what the stock taillight used, about 12% of what the stock low beam required! I don't think I'll really use it for night riding, but it'll certainly keep the piggies off my back for needing a light on during the day.

Below are a few more videos of testing the light throughout the finishing touches:













That headlight is freakin PIMP! I only use this word a MAXIMUM of one time per month...usually on an entire bike, and although it does apply to your bike, the headlight blew me away.

Is there any way you could do a easy write up for someone like me to use on how you built it with part numbers? I followed the link but i had problems deciding which parts you used. thanks if you get a chance.

Have a great one.
Thank you!!!

I can definitely do that. I've been asked just a couple days ago to do it elsewhere, no reason I can't do it in both places! I'll try to write something up and leave room for others' improvements.
This all so over the top goodness - crazy shit!

Gotta bring this thing to BUB Speed Trials in August - we're going to try and get as many DTT folk out there as possible. I want to see this thing run in person!

Keep up the awesome posts and great pics - you're building a resource millions of people will be able to read for all time - just don't lose the pics online :)
Subscribed too. I was also on the 305 forum when I build my cb77 cafe but it's sold. I do recognize your user name.

I'm mostly interested in the LED headlight as I am planning one for my bike. The rest is good ole reading for the mind. Awesome engineering!

Probably the first fuel injection fitted to a vintage bike I've ever seen! Just like my Duc S2R1K, you'll be able to connect the ecu to a pc and fine tune it. You'll need an exhaust monitor to determine CO2 levels to dial in the fuel air ratio. If not, then tune it the old fashion way (plug readings). Will the ignition be tunable too (different curves)?
eyhonda said:
You'll need an exhaust monitor to determine CO2 levels to dial in the fuel air ratio.

check the pics to see the wide band O2's in the head pipes :)
Ask and you shall receive! Here is the official build your on LED headlight thread, feel free to comment more on it in there!


dp9 said:
check the pics to see the wide band O2's in the head pipes :)

Ahh, I see. The sensor you referred to is for O2. I meant CO, not CO2 or O2. Actually, I was thinking more along the lines of static tuning.

Check this link out:
It reports CO levels from exhaust, which in turn is related to the fuel-air ratio.

Exhaust gas analyzers have come down in price for use by home garage mechanics. I have a PC tester for my Duc and it functions best if using the above tool to monitor fuel-air ratio (actually CO levels) as you increase or decrease fuel to the injectors (by software control) when linked into the EFI system. You adjust the fuel based on an ideal CO level range. I don't have this analyzer. So, I just tune it based on the plug readings.

So, I was wondering if this system also has this ability to connect via a link to a laptop to tune the fuel delivery. The oxygen sensors on the headpipe might work if the signal can be accessed via the link. But remember, it is (I think) closed loop. So unless the system can go open-loop, you can't adjust the fuel. Closed loop assumes the systems will adjust the fuel itself based on readings from the O2 sensor and a hard coded fuel ratio number. But, maybe you can adjust the fuel-air ratio, not the fuel amount??

On my Duc, the stock ECU is closed loop. I got it reprogrammed with software that is open loop and I removed the O2 sensor. Now, it just force feeds the fuel based on throttle position (load) and rpm, not based on an O2 reading. Anyway, just curious how this system works.
looks cool. is measuring CO more accurate than measuring O2? from the item description it appears to be more for emissions than turning.
It is explained in the manual that can be downloaded.

CO is directly related to the fuel-air ratio. Once calibrated to 2.0% in air, it can sense to an accuracy of 0.5%. The higher the CO level, the richer the fuel-air ratio. Stoichmetric reading of 14.7 looks to be about 0% CO (pg 16). As it gets leaner, there is no CO level to measure. So, it is only accurate in the rich region. 0.5%-1% CO is slightly rich. I suppose if you have a lean condition, you have to richen it until you see the CO level rise slightly. Otherwise, with this tool you can't measure how lean it is. Who cares? Lean is mean anyway!

Is it more accurate? I don't know. Either way, the O2 sensor is used for real time adjustment, while the CO sensor is for static tuning. But, you can static tune with an O2 sensor if you have access to the signal (input) and access to fuel delivery (output). Can you tell I'm an electrical engineer by day? ;D
It seems CO is one of the common analyzed gasses for emissions. I don't know about the accuracy of it, but it is good at showing how much unburned fuel is left in the exhaust, basically the opposite of O2 sensing. Each gas in the exhaust will give similar but slightly varied information about the cleanliness of the burning of gasoline in the specific atmosphere. It is far cheaper and still fairly accurate to simply measure the O2 in the exhaust pipe to see how efficient your fuel is being consumed. It is well known that, for standard gasoline, about 14.7 molecules of oxygen need to bond with 1 molecule of oxygen to completely burn. This is considered stoichiometric and is therefore 1 lambda. Other gasses exist naturally in the atmosphere, mostly nitrogen. Some analyzers measure NOx which appear in a lean burn or when the combustion process has too much excess heat, thus possibly warning of detonation. Hydrocarbons are also a common measured gas and usually mean a misfire and are long strains of the same hydrocarbons that compose gasoline itself. Each exhaust gas simply tells another story about the combustion process, O2 can just tell the most about air/fuel ratio on both sides of lambda. CO, NOx, and HC usually describe one issue more accurately but have a much finer range. The trick to tuning with O2 alone is figuring out why the reading is what it is.

99% of cars and bikes that have fuel injection probably have an O2 sensor and nothing else. It is a relatively cheap tool to tell the engine computer roughly what the mixture should be. Closed loop is sometimes misunderstood. All it means is that the ECU has control over the fuel injection and timing process using readings from an exhaust sensor. Open loop is rare, but just means that the exhaust sensor is only for informing the tuner, not the engine computer or is merely for safeguard actions like to halt an extremely lean condition, but cannot alter the tuning.

This ECU can support closed loop or open loop tuning. It will output to a laptop for data and can use a wide band or narrow band O2 sensor for closed loop operation. I'll only use the O2 for initial tuning, maybe even use closed loop for some street riding at first (it'll only permanently adjust tuning blocks by a couple percent at a time so open loop tuning needs to be close) and then pull it off once I'm happy with how it's running. Either way, the ability to tune that many cells of the engine's volumetric efficiency is going to be miles of improvement over the old flat slide carbs.
oh, so you wont have those attractive O2 sensors sticking out of your head pipes for ever? thats a shame ;)

speaking of the sensors, do you think the placement is a little close to the head? or to rephrase, why did you place them where you placed them? even on engine dyno headers I normally see them a couple inches farther down. of course that was on large displacement domestic v8's, so maybe its different.
The further down the pipe you mount your O2 sensor, the slower the response and therefore less accurate your adjustments will be. Because the gasses flow at different speeds at different RPM and loads, the delay can sometimes be tough to estimate. The only reason cars put their sensors in the tail pipe on the dyno is because it's easier than welding a bung. An experienced tuner will then have to carefully guess where which cells the AFR changes are associated with. Furthermore, the larger the distance from the headpipe, the more likely it is there's an exhaust leak.

Many OEM-placed O2 sensors in cars are in te exhaust manifold as close to the exhaust valves as possible to ensure quick response of closed loop systems. The thing you have to look for is water damage to the sensor. Too close and the spray of biproduct H2O will destroy the O2 sensor. The same is true when you mount it upside down or at too shallow of an angle, thus I used an angled bung.
Not a whole lot of time since I've been back from Daytona. I'm actually about to leave again on Tuesday for some meetings in North Carolina. Busy, busy, busy! I tidied up a bit today and looked over a few of the parts that came while I was away. I got the $75 bolt so I can properly mount the steering damper. It went on pretty easy, if with one nut that's incorrect. It works really well, I love it!

I also got back my laser cut VR sensor mount and got it welded up. I needed to file down some of the tolerance inconsistencies, but it should mount okay once I get the right bolts. I underestimated the length I needed and the ones I bought won't cut it. Throwing a coat of paint on it to make it look nice and clean, and I'll wire up the sensor!

I also painted my license plate bracket and will mount that tomorrow. Overall, not a bad day, just not a lot of real, tangible progress. I'm excited to get these last finishing touches out of the way so I can hear it putter out of 1962 and roar into 2012!







Real quick update. Spent the day buying bolts, unfortunately, the only ones I found were for my center stand. It seems the vibration from riding knocked one nut completely off, leaving a crooked bolt to hold on one side. Even the other nut had loosened.

I test fit my freshly painted VR sensor bracket which looks and seems to mount perfectly. As I said, all I need to do now is wait for the proper hardware. As you can probably better see now, there's a little cut in the plate so I can still check the timing with a light.

I also ruined a gas cap trying to figure out how to fit the barb fitting so I can send the return fuel back to the tank. I slowly drilled bigger and bigger holes, deeper into the assembly. Without knowing what exactly was inside, I accidentally bent the little dual-sided clip that grabs the gas tank itself. After realizing my mistake, I hacked off the bottom to better look for a solution for next time. I think I've got it, I just need to wait for the replacement to arrive. Below is what it'll look like once it's not all useless and stuff.



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