FJ600 Project | Page 2 | GTAMotorcycle.com

FJ600 Project

turbofj6

Member
The FJ motor (as you know) is air-cooled and has a smallish oil cooler. I will probably look into a larger oil-cooler but that would be the only change I can make.

The Seca Turbo, from which I sourced the turbo, was also air-cooled with a small oil cooler and had a full fairing. The turbo on that bike was also located behind the engine with little airflow. I am not aware that the the Seca Turbo suffered from cooling issues.

The FZ600 which had the same engine and cooler also had a full fairing.

Does the engine in your FJ run hot?

Chris
 

turbofj6

Member
Man, that FJ frame is looking even less capable...... :eek:
I agree, and will address the frame issue after the exhaust, intake and a few other pieces are sorted out. In the absolute worst case scenario where I have to leave it as is, I will just call it "tuned chassis flex".
 

GreyGhost

Well-known member
Site Supporter
Craziness.

Question - are you going to improve the cooling somehow?
That's a good question, but he doesn't have a lot of options. A bigger oil cooler can only help so much.

If he wants to make semi-sustained high hp, I would consider a water spray system to mist the block and give him some evaporative cooling. Replacing the stock battery with a lithium frees up the space for the pump and tank. If this bike is for street use, he may be ok as you can only make big numbers for a few seconds before you have to back off.
 

Matt Rain

Well-known member
Site Supporter
The FJ motor (as you know) is air-cooled and has a smallish oil cooler. I will probably look into a larger oil-cooler but that would be the only change I can make.

The Seca Turbo, from which I sourced the turbo, was also air-cooled with a small oil cooler and had a full fairing. The turbo on that bike was also located behind the engine with little airflow. I am not aware that the the Seca Turbo suffered from cooling issues.

The FZ600 which had the same engine and cooler also had a full fairing.

Does the engine in your FJ run hot?

Chris
The original engine ran quite cool with the oil cooler. Operating temp on the highway never went much above 80c. I’ve recently put in a rebuilt Radian engine that lacks the cooler and the difference is huge (probably in no small part because I’m still breaking in the new rings.) On the highway it hovers between 90-100c but with any kind of stop & go riding it shoots up to 120+. I’ll be moving the old oil cooler over to the new engine this week, curious to see how much of a difference it’ll make.
 

turbofj6

Member
Thanks for the information Matt. Would you mind letting me know how much cooler it runs with the oil cooler. Knowing that would help me decide what cooler to run. Why did you need to replace your engine??

Thanks,
Chris
 

Matt Rain

Well-known member
Site Supporter
Sure thing! Will keep you posted. I’m grabbing the cooler as I type this.

One cylinder was burning oil - I could live with the frequent top-ups but the smoke show was getting embarrassing. This kid put up a freshly rebuilt ‘89 Radian engine on Kijiji for 300 bucks (!) so I had to jump on it. I’ve put 400kms on it so far and it’s running mint (if somewhat hot.)

Live pic: https://i.imgur.com/Nb4HfiQh.jpg
 
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Matt Rain

Well-known member
Site Supporter
Thanks for the information Matt. Would you mind letting me know how much cooler it runs with the oil cooler. Knowing that would help me decide what cooler to run.
Well, after doing almost the exact same 70-km loop in very similar conditions (mid-day, hot & humid, light traffic), I took a pic of the temp gauge right after jumping off the bike:

Sans oil cooler (~97c)


With oil cooler (80c)


I’m no engineer, but that seems pretty damn significant. I saw roughly the same difference while cruising at highway speeds, 85ish vs 70ish.
 
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GreyGhost

Well-known member
Site Supporter
Well, after doing almost the exact same 70-km loop in very similar conditions (mid-day, hot & humid, light traffic), I took a pic of the temp gauge right after jumping off the bike:

Sans oil cooler (~97c)


With oil cooler (80c)


I’m no engineer, but that seems pretty damn significant. I saw roughly the same difference while cruising at highway speeds, 85ish vs 70ish.
I call that a success. Not just for the bike, but for your poor legs. Pulling 15 degrees out should make it much more comfortable to ride (unless the oil cooler is dumping all its heat onto you).
 

turbofj6

Member
Thank you for the cooling information Matt, most appreciated! It has lead to the decision to at least start with the stock cooler when I finally get it running. I'll monitor it and if need be, I'll get a bigger cooler.


So it's been a while since I've updated this. But that doesn't mean work hasn't progressed. Unfortunately, the majority of the work over this month has been undoing issues that I created several years ago. Here's what I've been doing....

Here is an old picture of the frame. Many years ago, I added the cross-member between the downtubes. It seemed like the right thing to do at the time. Some years later, I took the bike to a shop to install the turbo and they added the mount that you see here.

https://i.imgur.com/F5ryqyW.jpg


Here is the frame with the motor and turbo installed. You can see the mount.

https://i.imgur.com/9d0FHvo.jpg

The problem is that the turbo is solid-mounted to the frame. The engine is rubber mounted and the only thing connecting the 2 is the exhaust header. I'm pretty sure that the vibrations from the engine would rip the header apart in no time. So, I had to build a mount for the turbo that connects it to the engine instead of the frame.

Here's what I came up with. Bear in mind that it hasn't been dressed up and powder coated yet. It doesn't look like much, but here it is:

https://i.imgur.com/GE6resJ.jpg

and here it is installed:

https://i.imgur.com/zcNBfJY.jpg

It bolts securely to the bottom engine mount as well as the top mount. It is secure and I think it should take care of this potential problem.

Then bolt on the oil filter cover... https://i.imgur.com/PEVPoEm.jpg <-- see the oil cooler mount here (see below)
Then bolt on the turbo... https://i.imgur.com/SA0vUBQ.jpg
Then bolt on the exhaust header and waste gate tube... https://i.imgur.com/UYBBYiH.jpg

CRAP!!! the pipe in the picture (that you can see into) should mount to the exhaust coming out of the turbo. It is not possible to connect them because the oil filter housing extends too far. The oil filter housing extends too far because the oil cooler mount goes between the motor and the filter housing (you can see the oil cooler mount in the picture above) . That oil cooler mount was not installed when they built the pipe. So, now I need to reweld some pipes so that everything bolts together. Not a big job, just somewhat annoying because I thought this part of the build was almost done. However, live and learn I guess. I would have already fixed it, but I ran out of Argon which makes my welder unusable...

Project 2: In addition to the turbo mounts, I've made good progress on the front half of the airbox. I roughly built it and am having a shop weld it together. Hopefully, I'll get it back soon and post some pictures.

Project 3: I've also managed to mount the air filter...https://i.imgur.com/HbS9L1K.jpg Before you say anything, I hate it too. It's right behind the front wheel and interferes with the belly pan. It will end up very close to where it is, but turned 90 degrees. I will build a carbon fibre guard to protect it from debris.

Project 4: One last thing that I started wrapping my head around tonight is the frame. Here is what I'm starting with. https://i.imgur.com/ISDDx01.jpg

I plan to fill the large triangle with sheet metal. Here is my first attempt at a 15-minute cardboard template. I will probably go through 10 templates before I try and make one from steel. https://i.imgur.com/jYJSMQ0.jpg

That's all I have to report for tonight and will try and post more often as things happen.

Be safe,
Chris
 

GreyGhost

Well-known member
Site Supporter
If you ride in the wet, won't a bunch of water get up behind your triangle and be trapped between it and the frame? Maybe stitch weld the bottom and leave some gaps to let the water out?
 

Brian P

Well-known member
Moderator
Site Supporter
Definitely; leave a little opening at the bottom corner so that stuff doesn't stay trapped in there.
 

turbofj6

Member
Water is definitely something to think about and you both make an excellent point. Having thought about it more, I will be moving the plates to the inside of the frame rails. I was only planning to fill in the sides of the frame and not the bottom so air can continue to flow through the frame. This is also the area where the coils mount and the plug wires come from so closing it in wouldn't work.

One advantage to moving the plates to the inside of the frame rails is it provides a better place to mount the CDI box, flasher relays, nitrous solinoids, etc. I will create template number 2 tonight and see how it all pieces together. Right now, all of the electrics are under the seat.

Will share pictures tonight (hopefully!) and look forward to your thoughts.

Be Safe,
Chris
 

Malks

Well-known member
I can't tell from the pics, but will you be able to change the oil filter without removing some of the pipes from the turbo?

I had an '84 FJ600 that I rode for 10 years. It came with an aftermarket 4 into 2 Yoshimura exhaust that sounded great, but I needed to remove it for every oil change because the pipes blocked access to the filter housing.
 

Riceburner

Well-known member
I can't tell from the pics, but will you be able to change the oil filter without removing some of the pipes from the turbo?

I had an '84 FJ600 that I rode for 10 years. It came with an aftermarket 4 into 2 Yoshimura exhaust that sounded great, but I needed to remove it for every oil change because the pipes blocked access to the filter housing.
lol....mine too. 4 into 1 Yosh. Pain in the butt every time.
 

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