XJ600/FJ600 Custom Bike Build with Microsquirt

First time creating a thread, so bear with me, I'll learn the formatting as I go.

1984 FJ600, same as the XJ600.

Picked the bike up for $120 in 2012, have been in the process of building it into a cafe/brat/race style bike.

The goal of this bike is to be able to bomb it down a gravel road, go on 3,000+ mile trips, and to handle well for an 80's bike in corners. In all three aspects, I'm only expecting it to be mediocre in all, and just be a well rounded bike.

I have tossed around the idea of a turbo, and EFI for a while, and I have just recently bought a lot of componets for the EFI conversion. Throughout my build, I will be using most of my own ideas, as well as adapting what other people have done on their bikes. This will not be another lost and abandoned efi bike build. I will continue until it is "complete" (no bike is ever complete).

Little back story of the bike:

Purchased in 2012 off of craigslist, and it was in terrible shape. The wire harness had some housing solid core wiring in it, with wires twisted together with the twist caps. The carbs were stained green with old gas, and the gas in the tank was the so orange, I could hardly believe it was gas. It appeared that someone wrecked it a long time ago, and then let it sit in a field slue (spelling?).

The wire harness was mutilated, as mentioned before. Power wires and ground wires were connected, causing the regulator, cdi, and coils to get excessively hot. After purchasing a wire harness off of fleabay, I could get spark, but only on one side. Did the usual diagnostic stuff, as well as changed the oil and filter, and found that the cdi was not driving one side of the coil. Bought a used cdi, and fixed the spark issue.

On to the carbs. After cleaning them, the pilot jets were clogged and stuck in the carbs, with the heads stripped. A common thing that people don't understand, is that the carb stuff doesn't have to be super tight. In my experience, I have never had a main or pilot come loose. Anyway, using some ingenuity, the carbs were coming along. New floats, carb kit, o rings, all that stuff.

Now lets fire it up. I had previously removed the exhaust to get at some shock stuff, and when I installed it back on, I left the mid/cross pipe out of the exhaust, less restriction is good right? Sure. (keep this in mind for a little bit). Put fuel in the bike and started cranking. Had to use the 'ole screwdriver bridging the solenoid trick because the hand controls were toast. Cranked about 6 times and it popped right off! Pretty good for not running for, to my knowledge, 16+ years. All of a sudden the fuel comes pouring out of the intake and overflow of the carbs, floats are too low, ok, no problem. I turned the gas off on the tank, because I figured I might as well let it run for a bit and cycle some oil, since it has not ran in quite a while. Well let me ask you a question. What happens to an engine when you cut the fuel? It used the fuel in the carbs and started to starve for fuel. Okay, no problem, it's expected, I have done it many times before to just let it run to get the fuel out. Well, when it starves for fuel and gets lean, it back fires. Shocker I know. So remember when I took the cross pipe out of the exhaust? All that fuel that poured out from the carbs went right under the engine where that pipe was. Exhaust likes to go through the path of least resistance, so when it backfired, it lit all the dripping gas on fire.

So there I was, with no fire extinguisher or water to put my bike out. So trying to keep this short, I ruined my "new" wire harness, everything electrical on the bike, relays, solenoid, all that. Managed to take the tank off, seat, and I kicked the carbs out of it to separate the fire. Cleaned it up, and there it sat.

So now, about a year later, it was time to get back at it. I have been currently building a wire harness from scratch, and ordered the started solenoid, using blade style fuses now, making my own starter relay, kill/start switch from a CBR1000rr, light/horn/signal switch from a 09 R6. After "finishing" version 1 of the harness, it fired right up again! Sweet. Shortened the wires to where they will actually be at when it's finished. Rode it around a bit with no brakes, just shifting down and using the kill switch and engine braking. It rips! And is loud as hell, because I chopped off the exhaust because it weighs a ton, and I will be welding up my own 4-1 exhaust. Open exhaust with pod filters, and it runs actually not bad. All the nay-sayers that talk about cv carbs are terrible with pods must just be unlucky because this thing runs great, a little lean, but that's fixable.

Throughout this time, I have always wanted to convert it to EFI using microsquirt, why? Well why not. It is a learning experience and will transfer to other bikes in the future. So within the last year I have been consulting with a friend that has a lot of experience building 600+ hp evo's, lancers, and a 400 hp Hyundai Elantra drag car with 35 psi on stock engine, and buying EFI stuff, throttle bodies, sensors, and researching about it. This black Friday, I purchased a microsquirt controller and a CLT sensor.

 

Reserving some space in case I need to add some stuff.

 

Pictures of the first steps of stripping in down and some small progress.

One of the first pictures of the bike


Taking apart the carbs


Stripped down-ish


2007 R6 front brake master cylinder and CBR1000rr kill/start switch. Very preliminary parts pictures and planning. Things will pick up in a bit.

 

Looking forward to watching your build!

 

Needed to do a frame swap, into a '85 frame, but when I got the title back, it said it was an '84, so '84 it is.

A note for anyone thinking about swapping frames, there are a few differences in the frames. A couple fairing mount points are different (doesn't matter to me, it will be fairing-less for me), the coil bracket is different, so I assume that the coils are different from 84-85. Coil brackets are not an issue if you can weld. And for whatever reason, I could not get the exhaust to fit for the life of me, it was about a half inch off, so I cut it off at the headers.
The stock exhaust must weigh close to 20lbs, so that is no good for the power to weight ratio anyway. Building a custom 4-1 exhaust with a Cone-Engineering collector, and a Dime City Cycles muffler.



Engine in its "new" frame.

Repacked the steering stem bearings, they look good, and the bearing races look fine. Good enough for an 80's bike, with unknown miles on frame or engine.
Mounted up the forks and swing arm, and finished bolting the engine in. The engine is pretty damn heavy to be moving around by yourself, but I managed. After this I rewarded myself with a nice cold Budweiser.

 

Built my own wire harness, very rough version, we'll call it Version 1.0.
Here is a video of the first start up of the bike, and the first time ever moving under its own power ever since I have owned it, and for about 12-16 years before that.
https://youtu.be/MTbY_Bal0aU

The video has some earlier videos with the old leaking worn out tires, and some with the new tires. Here are a few pictures of the new tires.

VERY IMPORTANT NOTE:
The front tire, which on the internet says it is a 110/90 V18, but for whatever reason, the Shinko 230 110/90-18 16v is waaay taller than what was on it before. If you're not planning on running no front fender then, no problem, but the tire rubs on the stock fender. I am planning on just running no front fender until I need to replace the front tire.
I'm not sure how this affects handling of the bike, since the rear tire is only about a half inch taller than the front now, I'll be sure to comment on the handling and take pictures of wear patterns of the tires once I start riding it.


Wiring progress

 

Fork seals were shot, and it needs new dust seals, but those can wait until the bike comes further along.

Here is a fork tool that I welded up, welds are garbage, but it works and it won't see much stress or general use. More of a specialty tool, like most bike stuff.

"A welder that grinds his welds isn't a good welder, he's a good grinder."

It is used for holding the internals of the fork, so you can remove the bolt that in the bottom of the fork that holds it all together. You then pull everything out, and then you will be able to get the seals out.

I was considering fabricating some of these fork disassembly tools, with some better welds, and maybe sell a couple, who knows.
Who is working on '84 fj/xj's anymore anyway. Few and far between.
Anyway, on to more bike stuff.

 

Now this build thread is all up to date. 12/9/15. Will be posting as I go. Probably won't go in great dept on the boring stuff, but I can send detailed pictures of parts if you have any questions.

Got the Microsquirt in the mail yesterday, and throttle bodies from a 09 FZ6R, which are 33mm, which is only a 1mm increase from the carburetors, so I should not have many tuning issues, (famous last words).

I also will be running a full data logging set up with Innovate products including the SSI-4 and the LC-2 wide band with their pocket logger. I used this set up on the blue 07 R6 that was in the previous pictures with great success. Going to adapt a GM knock sensor or a CBR600rr knock sensor to the FJ, I'm sure I will have to drill into the block somewhere. If all else fails, I made an electronic det-can out of an old personal listener thing that looks like a walk-man. Worked well for hearing the knock points.

Little side note, the R6 has the largest diameter throttle tube of any other stock bike out there, if I recall correctly. This is desirable because who wants to have a long pull throttle, flapping your elbow around while shifting. But, the R6 cables do not fit with the stock FZ6R throttle cable mount, the pull cable is short. So there is three options, get a longer pull cable from Motion Pro or equivalent, get the cables from the FZ6R, or modify the stock cable bracket.

These cables most likely will not work with the stock handle bars, or dirtbike bars anyway, so I am sure I will be getting new cables.

Pictured: Microsquirt with CLT sensor, 07+ R6 Throttle and 09 FZ6R Throttle bodies.


Detail of the "pull" cable that is too short.

 

haha - love it. I had an XJ600 too (early 90s) it went well but if I recall used way more fuel that my mates modern (then) CBR600.. maybe the EFI will help on that aspect. Will you have to build special adapter rubbers for teh throttle bodies to head ? Do you also need a high-pressure fuel pump like in car injection systems ? I wouldn't really know wher to start with this so I wish you best of luck..

 

Yeah, apparently it is supposed to get 45-55 mpg, my R6 got about 42-50, so if I can keep it above 40 mpg, then I'll consider it a success for fuel mileage while cruising. I'm expecting to be putting in many hours of tuning.

Yes, I will be making custom adapters for the intake boots, conveniently enough, the outside diameter of the stock boots are very close to the outside diameter of the new throttle bodies. So I will have a friend machine them out of aluminum, and then I will use silicon hose to mount them together. I will then use a die grinder to smooth out the transitions and such. I will probable post some simple CAD drawings of my ideas, and pictures of the parts as I make them. So many options and possibilities, so I'm willing to do whatever I have to, to make them fit. So far, in my head, it should work... hopefully.

And yes, I will be getting a high pressure fuel pump. I'm not sure if I can use an in-tank fuel pump outside of a tank, or I'll just use some sort of an automotive one, maybe a Ford fuel pump, as I think that has been used before. I have also seen some people use a Honda Ricon atv fuel pump, but for my application, it looks like it might take up too much room. The tank on the FJ is huge, so I may try to fab up an in-tank pump. We'll see.

 

Interesting ! What does teh R6 use for the pump - can that be adapted ? And sensors ? What inputs does teh microsquirt need ? Sorry for all the Qs - just interested as I looked into this for my VW bus at one point but never that seriously..

 

Looks like we might have a real clean micro-squirt project the goes the distance this time.

So many others get started, then big down with problems, then the people either give up or just disappear.

This may be a good one to watch.

 

I have an 2003 R1 intank fuel pump I would donate, however they are around 100mm diamter and 180mm long so I am not sure one would fit in one of those fuel tanks

We run an external airtex E8445 fuel pump on the sidecar which is about 50mm diamter and 150mm long, but Airtex have a huge range of internal and external pumps

 

I'm super interested in this. I have an FJ600 with less than functional carbs.

One thing that I keep trying to figure out about FI setups is why bikes always have multiple throttle bodies where cars usually have one.

 

Yeah but same with carbs though right ? Performance vs economy reasons I guess.

 

Vast majority of high performance FI cars run one TB.

It's not the same with carbs. The difference is that with a single carb what travels through the intake runners is the air/fuel mixture. Long runners can be problematic, as it's going to start separating, mixture might get inconsistent. With port injection, the intake plenum has only air, fuel is sprayed right at the port.

 

The R6 or R1's use an in-tank pump, it's fairly small, I don't know any numbers on it, but if those pumps will supply enough fuel for the R6 at 16,500 rpm, it will be fine for the FJ. Keep the questions coming, I'm learning this stuff as I go, and trying to give some actual, factual information that others can use on their projects.

 

I would pay for postage or pay for it if necessary.
What I was thinking for the in-tank pump is, that I would buy a used R1/R6 tank, 03-05 (just because they are older and not worth as much), ideally with damage to the tank, so it will be really cheap. I would then cut out the gas cap cup/bracket, and the fuel pump mount out of the tank. I could fabricate it, but it will be A: I may not have the tools to do it, or B: just time to make those pieces. I would then have a friend of mine TIG weld them in to the FJ tank (I really need a TIG).

So then, I would be able to use a newer style gas cap, which would look cleaner, and have a lock. Not that the lock is important, but it's nice. I took out the lock mechanism on my cap because I only had one key, and I was getting a new ignition for it anyway.

Thanks for the info on the dimensions of that pump. I'll have to do some measuring and see if I can get it to fit. It may be hard since there is a tunnel on the tank for the frame, we'll see.

Thanks also for that info on the Aitrtex pump. Looks like something I might end up getting.

 

I have wondered that too, with an FI set up, one could just have the injectors right outside of the ports, port injection, and then have one throttle body. I am not 100% sure, but I have read that sometimes if you have too short of intake runners, then it may be hard to tune. Like putting pods and open exhaust on an old bike. Some say you need a larger intake plenum, so running one throttle body may help. (That is before the carb or throttle body, so I'm not sure about having just a longer intake track after the throttle) I do know that the reason why the new R6's have the variable intake is so that they have long intake runners for low rpm, and then it lifts to shorten the runners at high rpm. Those are before the throttle bodies, so that will probably also make a difference.

There is a guy that turbo'd a XS650 and he used injectors right at the ports, and one throttle body. That was also for ease of attaching the charge pipe to the throttle body. Turbo-ing might also make a difference, where the air is under pressure, and it probably does not matter as much how long the runners are after the throttle body.

If I get around to it one day, maybe on another bike, and with some better machining skills, it would be interesting to see what each style would work best, on EFI.
Ease of tuning, power, mileage. Make two separate systems, and try it out.

I do agree with a100man, it probably comes down to performance vs. economy. If Honda isn't using one throttle body on their $600K(?) race bikes, then I'm sure they have a reason for it.
Just like Yamaha engineers decided that the YZ450f makes more power with the cylinder head backwards.

Maybe the air velocity is better with single throttle bodies. If so, it would be really interesting to see how single throttle bodies (that are the correct size for flow), would perform on a LS engine or some kind of V8. Sounds like a good science fair project haha

 

Here are some initial ideas of mounting the throttle bodies to the FJ. I would make the intake boots that bolt to the engine out of alumium, similar design to the stock rubber ones. Then there will be a plate that I will either silicon hose and clamp with a flange on it, that bolts on to the intake boots of the new throttle bodies, or I will have the stock flange, weld on a tube, then weld that onto the other flange, that will then bolt on to the new throttle body flange.

I was wondering about weight, and if I have those longer intake "boots" out of aluminum, will it put too much stress(moment arm) on the cylinder head and intake boot bolts? I will weigh the throttle bodies and carbs, to see what the difference is, then I'll make a decision. I might also just make a little bracket that the throttle bodies will bolt to, that will connect to the frame. Engine is hard mounted, and it doesn't really vibrate for an older bike, so we'll see. Might be a trial and error thing.

The new intake boots being about an inch or two longer, shouldn't have an effect on tuning, but I'll find out I'm sure.

Here are a few pictures. CAD drawings in the back.


Where that 10mm ridged section, where the hose clamp goes, on the stock boot is (the top one in the picture) That will be where the plate will be, might have to use some imagination.

Also, I bought an e85 content sensor, the Microsquirt has a pin for it on the ecu, so, why not? Nice thing about this project is, is that there will be nothing that is left of the 80's fuel system, so I should have no issues with e85. My reasoning on why I wanted to add it in is that say I go to a gas station, and they don't have 91, but they have e85, e15 or whatever, I can run it. Will the injectors be able to handle that extra fuel demand? I think so, since the injectors on a 03 r1, and injectors on a 05 r6 are the same, and the throttle bodies are the same, these injectors should be fine, since the FZ6r revs higher, and makes more power. The nice thing about the Megasquirt/Microsquirt, is that with that sensor, it will blend your e85 map, with your 91 map, so you'll have the right fueling and ignition timing for whatever percentage.

And if anything, it will be a learning experience.
Which is the whole concept behind this build. Build a bike that I like, hopefully others as well, and learn some new skills or general knowledge.