Simmy's Naked Turbo Project

Just looking at this closer now I don't even have the heating element hooked up.
AEM state the minimum Power/IO connections required to operate the gauge are switched 12V (5A fuse) and ground, the Red and Black wires, so that's all I hooked up.
The wiring schematic shows the heater element Brown + and White - 0-5V and optional??

Is yours an AEM gauge? Perhaps I should follow your advice, I could just put a 2 prong plug on it and plug it into the pig tail for my battery charger/electric vest once the motor is running.

 

14point7.com

 

OK I had it wired correctly.
I had to buy a 5A fuse, once I turn on the key the unit begins heating the element in the sensor.
Takes about 10 seconds to complete heating (20 on the scale) then you can push the starter button.

Bezos just dropped off the valve shim I needed so working on buttoning up the valve cover.
The sensor is supposed to have 18" from the head, I mounted them too close, hopefully still reads ok.

 

OK I set the valves, set all carbs at 2-1/4 turns on the mixture screws then balanced them with the mercury stick.
I left it idling at a very steady 2,000 rpm.
At this idle the FPR stayed between 13.0 and 14.0
I had to stop thinking that it was 13.0 parts air to 1 part fuel
Instead just think of it as oxygen (bigger number) more is leaner, (smaller number) less oxygen - richer.
According to what I read this is pretty much what you want to see at idle.
Under turbo boost best to stay between 11.5 and 12.0.
11.5 is target and anything over 12 becomes dangerous
Nothing left but to put the tank on and go for a rip!
Should be fun to see where the stock Yamaha main jets read, very cool tool!
Then do it again with cylinder 2.
The stoichiometric ratio is 14.7:1 (or lambda 1) which means 1 part fuel needs 14.7 parts air to fully combust

 

Today I finally took the bike out to test the FAR gauge.
I wasn't out long because it was really cold, the spitting rain didn't help either.
Between hypothermia, traffic, grabbing turbo boost while looking at the gauge I did learn a lot.
Just before the boost comes on, say at 5,000 rpm the F/A ratio dips down under 11 then when you ride the boost it starts leaning out but still under 12:1.
When accelerating under 5k the readings stay around 13, 13.5.
Closing the throttle any amount anytime leans the reading out immediately.
I really need a warm day and a deserted highway.
If I put my phone in a pocket aimed right it should keep recording it, that way I can just concentrate on riding the bike.

 

I rode the Turbo last weekend and it seemed to fall off power significantly when I got home.
The boost felt way down.
I thought maybe my imagination so I rode it this weekend and yes definitely a problem.
Registered about 4psi of boost so I started looking over all the vac hoses making sure nothing popped off.
Paid particular attention to the hose going to the boost gauge as that is basically aquarium tubing.
Found nothing out of place so started inspecting the exhaust connections to be certain I wasn't loosing pressure there.
I did find the gasket at the inlet to the turbo unit looking like it's 1/2 blown out.
It looks too suspect not to replace so no riding this one for a bit.

Time to look at the sidecar.
I struggled with a fuel leak at the bottom of the OEM petcock.
As a quick fix I ordered a Chinese petcock but the bike is starving for fuel.
Might even be the vac line, needs a closer look.

Hoping this gasket was my problem.

Sidney was in position to for a good look and she agrees, might just be my issue.

 

I've ridden this bike just 1,800 kms depending how far off my ODO is.
I can't be certain if I have an FZ600 or XJ650 speedo gear box.
Might be the same not sure but I have a 16" wheel in place of 19"
I actually just started feeling comfortable with the handling, it does feel different,
much quicker steering twitchy even but still feels very stable at speed.

 

and much to my horror, the RH sidecover has a broken tab.
Amongst my spares I had another broken in the same place so common break
Not sure whether to try gluing a piece from the silver cover or just mold the tab missing with epoxy




This red one is almost cracked in half that's why I didn't select it for painting

 

Typical for that cover…..

 

I removed all the exhaust pipes between the head and the turbocharger to inspect the gasket at the turbo inlet.
It was still intact so I just put it back. I did find all 4 pipes were loose at the head which is where I was leaking.
All back together and working good, boost pressure back up to 9 psi.
A good reminder anytime you install new gaskets at the head pipes to tighten them after a few hours,

I did find a defect in the welding on my collector that's been there since new.
This didn't affect much since full boost has always been achievable but I gooped it closed with some hi-temp silicone.
Also moved my wideband O2 sensor over to #2 and observed fuel/air ratio very similar to #1.
I think I have enough information now to begin the big bore conversion, once this riding season is over.

 

Bike is running really sweet.
Just need to put some miles on before the season is done.
I need to remember how it feels now as a 653 before the 772 kit this winter.

 

I took advantage of the last warm weather here to paint my 772 big block last night.
The big bore install will definitely happen this winter.

 

It gets warm in Canada? Wonder how ya keep the Molson beer cold... Will say your 650 looks absolutely gorgeous!

 

Thank you @Brhatweed
I suspect Minnesota gets colder than Southern Ontario.

 

I suspect you're right on the cold, I'm not far from Mille Lacs and once all the lakes freeze over it gets real.

 

Hah! It gets real cold in order for the lakes to freeze over!

 

Bike wrenching season has officially arrived. 2 projects this winter.
Unfortunately my little workshop allows just one bike at a time.
I need to wake up the red one from a lengthy slumber and the Turbo gets a 772 kit.
Ultimately the Turbo project took precedent.
I need a 772 monster Turbo much more than another nice Seca.

 

@Huntchuks your reply is#666 and discussed things freezing over LOL

 

all the grunt work is done.
I'm ready to start dismantling the top end, doing it with the motor in the bike.
I painted this motor and I'm worried about the plastic sleeve Y put on the cylinder studs.
The last XJ motor I stripped down it was a real B sliding the block off the studs.
I think sometimes the material breaks up and jams the block from coming off.
Think I'll try unscrewing the studs from the lower case instead of trying to slide the block off.

 

This is the Naked Turbo coming apart to get the Big Bore Turbo motor?

 

Yes, but all I’m doing is changing the block and pistons. A motor change was going to be a lot more work

 

Ahhhh.... And yes, it would. I played musical engines this last summer with an XJ750J. CB900C engines are hard to pull too! And the head will not come off the block in the frame on those.

 

My original plan was to keep this motor completely original and modify the spare I have.
The spare was actually seized when I tore it down and there are many things I'm unsure about.
To bring it up to perfect standards would have been expensive.

I think I have everything needed, piston clips, gaskets, o-rings etc. to bolt it together.

Since I have a wide band O2 sensor I'm planning to leave the jetting as is and see which way it needs to go.
I expect the larger motor will spool up the turbo sooner so thinking I will raise the needles.
I can't remember if there are different grooves to move the circlip?
I pulled this pic off the net, it doesn't look like there are so I will need to shim them higher, need to find some washers for this

 

Decided to take a break at this stage.
As I suspected the block is stuck to the studs.


this is the shit Yamaha put on some of the studs.
I'm sure I made it worse by painting the block in place.
This is why I'm contemplating turning the studs in their threads,
I have some spare cases to see how easy/difficult they are to remove without heating the case.
Double nut method
Anyone know which studs got the covers?

 

All studs at the front with the exception of the two outside ones have those covers. You can see them through the fins on the block. You might be able to burn them off with a blowtorch if nothing else works. I haven't tried it but if you run out of options.

 

that makes sense as I did get the rear of the block loose, the front is stuck.

didn't think of that one, might be an option.
Hopefully I can get the studs to screw out. Once the threads move the rotation should break the paint holding these sleeves to the block.

 

Yes best option is removing the studs if possible. I used a wooden block too and a hammer to tap the cylinders which eventually freed the dowels without breaking the fins. Meant to add the stud at the front of the crankcase cylinder joint was seized on my 900 took a lot of heat and oil to free it.