Simmy's Naked Turbo Project

It's not meant for the suction side of a high flow pump. You can get inline strainers, usually the type you can clean, and this would be my choice. That filter would likely be fine on the inlet to the carbs.

 

The pump manufacturer actually offered a filter maybe strainer for the inlet as @Minimutly has suggested,
probably should have added it. This is the standard filter Chacal sells.

 

Which is a good filter. I have them on all my machines but I also don't have fuel pumps on any of them. A little digging into which type of filter or strainer is best for your application and you'll be set.

 

Boy is that a good looking bike...................

 

Right filter wrong application is all.

 

Yep, sometimes it's the simple things overlooked the most.
The weather is like summer here in Southern Ontario.
I introduced the Turbo to the stable today.
Here's my XJ collection.

Starting from the left, 911 Seca, 650 SecaT and FZ600
The shortest stroke is the 911 and the longest stroke is the 599.

 

The 911 seca - did you do a build thread for that?

 

That is a pretty herd Simmy. I am not big on green in general but you sure have made it look good. Well done! Makes me feel guilty about my very cheap, Midnight Maxim 750 rat bike. Don't tell Hogfiddles I said that......
John

 

not a build thread, just a discussion thread.
https://xjbikes.com/forums/threads/highly-modded-650-seca.85760/#post-505494
I've had this bike and sidecar since 1989 so I did all the mods before I was even aware of this forum.

Here's the thread I started for my FZ600. Nothing too exciting as bike is essentially stock
https://xjbikes.com/forums/threads/fz600-resto-the-hotrod-xj.99949/

Here's another thread I have in Other Bikes
https://xjbikes.com/forums/threads/a-real-scrambler.100460/
I have a very detailed build thread on the BSA Unit Singles forum but I think you need to sign in to view the pics
http://www.b50.org/phpBB2/viewtopic.php?f=14&t=4395

 

Something tells me you like green.

Awesome bikes!
I remember going through the Seca X thread of yours and am still amazed you pulled that off.

And now you create the 650Seca Turbo.
Needless to say, I'm seriously impressed.

Tony

 

Wow, the 900 was built in '97....
Impressive build.

 

Yep, green is not just for Kawasakis anymore!
I think Kawasaki claimed the ugliest shade of green there is.

Thanks guys, your comments are greatly appreciated.

 

Nooo, the two tone green with the dark green flake was a great color scheme from Kawasaki.

 

agree, that looks sharp!
I was alluding to their racing colour, thinking Scott Russell's Muzzy superbikes.

 

I've been reserving judgement on this until I had some more saddle time.
So after some riding this last weekend I feel I can comment.
The difference in handling with the 16" wheels is huge, combined with the weight loss there is no longer any resemblance to a stock Turbo.
There is no way the stock bike would stay with this in real twisties.
It's no track day weapon but it wouldn't be completely out of place, maybe if I wasn't 60 yo I might be tempted.
I prefer its handling to my 88 FZ600 which is really too small for me.
The supermoto stance suits me better than the sportbike crouch for the corners.

I've got some chatter in the front brakes, hopefully new pads will correct this.
After the 1st ride last fall I noticed my left freshly rebuilt caliper was leaking fluid, I suppose the seal wasn't properly seated and it leaked fluid on the pads.
I replaced the caliper and the pads with some used ones I had so currently they are mix-matched set.
I haven't felt the urge to play with the boost controller. It's currently set to 14 psi and I'll probably leave it there.
I'll ditch the boost gauge and put the left mirror back.

 

I've taken inspiration from Mezzmo's videos and plan to begin building my 900 from completely bare cases.
I have a question to the motor rebuilders. How do you remove the bearing shells?
I'm not sure how much hammering or prying to get them loose they can tolerate before they're deformed.
Here's a pic of the Turbo cases with the worst bearing shell. You can see in the pic how deep the gouge is.
I'm not using these cases so I can practice with these.

Also the bearing for the alternator is captive with no access to the back side.
How is this removed? I'm thinking about leaving it in place and sealing it over to protect it from degreasers, sandblasting and water.

 

Wow, I just realized how long it has been since I was that far into an engine...... in the early 70's I think. And those were car motors but still I don't think the bearing shells should come out with any difficulty. Your picture shows an opening on the outside of the shell you should be able to get something small and pointed into and pop it out without great issue. But this is far from recent or expert opinion so take it for what is worth.
John

 

I tried prying the bearing shells and most of them just popped right out.
That was the case with the Turbo motor but the 900 had a few shells which didn't budge so I struck them with a wood block and a hammer until they rotated out.
I was gentle so no damage done.

The 900 cases are etched as follows

the 900 crank stamped as follows

so all the main bearing shells are #2's if I'm understanding this correctly.
4(etched on the case)-2(stamped on the crank)=#2 shell.
This is convenient that they're all the same size.

the Turbo cases were etched as follows:

Turbo crank stamped as such

So the Turbo motor had
1st Journal 4-1=#3
2nd Journal 4-1=#3
3rd Journal 4-2=#2
4th Journal 6-3=#3
5th Journal 5-2=#3

Seems the 900 has the more consistently machined components.
What are the 2 lower etched numbers on the cases?

Something I wasn't aware of until the shells were removed, there are metered orifices I guess to keep the
oil pressure even across all the journals. They look like carburetor jets. Only 1 3 and 5 have them.

 

Middle gear shim thickness; see page 9:

http://www.xj4ever.com/catalog/frame-engine-id.pdf

That is correct. Debris and gunk can collect in those passages, so be sure to purge them adequately.

 

I took some time tonight to compare the connecting rods between the 650Turbo and the 900.
I measured the 900's to be about 1.25 mm's shorter than the Turbo's.

Turbo on top, 900 below

the difference is obvious in this pic

The Turbo big end has an oil groove that the 900 doesn't have.

I measured the cylinder blocks - 900 is slightly taller at 77.44 mm and the 650 is 76.98 mm.
I connected 2 900 pistons to a Turbo piston, there is a slight space under the Turbo piston but the 900's are domed so there is a lot of volume
around the edges of that dome. This really doesn't tell me much at this point without using a liquid to measure this volume.



With the combustion chambers I plan to slope the edges out to the 900 bores so that will gain some volume.
There is a slight bulge opposite the spark plug I've circled. I think I can gain some volume here by removing some of this.
With custom low compression pistons I think I can keep the external dimensions of a 900 close to the 650T.

 

question for @chacal
below pic is the cam chains out of the Turbo and the 900.
You list a different P/N for the 900 but they appear to be the same?
Price on the 900 chain is greater by twice? How come?

 

The aftermarket chains between the XJ650/700/750 engines and the 900 engines are about the same price ($10.00 difference); the OEM cam chain for the 900's is considerably more than the aftermarket chains (as is typical). Although they may be the same length, there may be a side plate or material (strength) difference between the two, I really haven't checked, but the OEM chains did carry different parts numbers (and used different master links), so there was something different about them. The 900 chains were made by D.I.D., which is a premium level supplier, while the 650/700/750 chains are made (I think) by Tsubaki, also a well known manufacturer, but not as well regarded as DID......but again, all this is supposition.

 

Note that the 650T uses a modified 750 rod (casting 5G200) which has an extra oil spray hole (both sides of the beam), whereas the 750's have only a single spray hole. The 650T also has those grooved bearing shells that you don't see on the other engines. Very heavy-duty-ish.

700 air-cooled engines use the 650 (non-Turbo) rods. 700 water-cooled engines use a unique rod, of course.

And the 900 rods (the 700 water-cooled, also) have the cap bolts installed from the "bottom up" (bolt goes thru the cap first) with the nut on the beam side, unlike all of the other XJ engines.

 

Hmmm, so ideally the 900 rods would be drilled for the 2nd hole and the Turbo bearing shells installed. Turbocharging really loads this bearing, Yamaha determined the need for it.
I'm sure you're going to tell me they aren't available as you don't list them in the catalogue.
Even if they were the cost starts to spiral out of control.
Perhaps I need to reconsider this project, why spend a bunch of money on this motor if it's long-term durability is uncertain.
I hadn't planned to mess with the conn rod big ends but I'll compare the 650T bearing shells to the 900's, perhaps I have most of what I need for this conversion.

This I was aware of, having read this was a solution to clear the cases, rotating around a 4 mm larger radius than the 650.

Thanks Len, this makes sense, I was probably comparing the OEM 900 price to the 650 aftermarket.

 

Unfortunately you are correct. They haven't been available for a l-o-o-n-g while.

I think that will work, so it depends on what shape those 650T bearings are in. Another option would be to make (have made) a set of custom pistons to accomodate the differences.

Either way, some bucks heading out the door.....

 

The ink numbers on the conn rods for both motors appear to all be 4's.
Stamping on the Turbo crank
3 3 3 2
so bearing shells are 1 1 1 2

Stampings on the 900 crank
2 2 3 1
so bearing shells are 2 2 1 3

So I need to find another #2 and a #3 conn rod bearing shell from a Turbo.
Then verify with Plastigauge of coarse.

 

There were 8 sets of Turbo connecting rods on eBay last night with the bearings in place.
I could buy one set and get lucky or buy all 8 sets and strike out, a crap shoot.
Maybe I'll contact the sellers and see if they will sell just the bearing shells so I'm not paying $60 shipping.
An option would be to just drill the 2nd oil passage through the 900 bearing and rod without the groove.
The 3rd option is to just use the 900 stuff as is and forget about it.
I suppose the 4th option is to just ride a 650 Turbo, LOL.

 

first thread on here I'm addicted to.. love to see other custom builds and like minds. nice!!

 

here's a walk around video of the bike



I hooked up the Colortune again, I was getting a blue flame but gave the mixture screws another 1/4 turn. They're all at 2-3/4 out and it's running really sweet now.

I'm still getting some shudder from the front brakes so I'll be trying another set of rotors I have.
I'll have another look at the wheel as there may be some powder coated areas not allowing the rotor to sit all the way home.
I found a listing on eBay for some Brembo floating discs listed for the 1100 Virago but they would be almost $600 for the pair.

Other than that I'd like to take a little off the fork spacers to soften them up a bit.
This thing really handles now, still haven't scraped anything even with it lowered an inch.

 

The ultimate hot-rod XJ...........

 

Really like that colour scheme.
Minty fresh.

 

Ultimate? not sure about that, I think you're overlooking @skylrk62 and his Turbo Maximus.
His high tech special might no longer be considered a hotrod though, that's a class unto itself.
Wait until I slip the 900 in, then we'll see

I always need a winter project up here and the 900 mill will fit the bill.
I think I'll build this motor with the standard 900 crank and con rod bearings.
I don't like the idea of drilling the additional holes through the 900 rods.
Thinking about getting an 891 cylinder block from Germany then ordering custom 68.5 mm forged pistons.
Go big or stay home, right?
Maybe in this case, going big you don't want to be far from home in case she blows.
The cases are currently at a local bike/machine shop drilling and tapping the tapered threads for the oil feed to the turbocharger.
Sandblast and paint then I can start this build.

 

You are an animal!

 

I went for a spin down my favourite country road this morning.
I love this bike!

 

Seems I've got more sorting with this thing.
Most of my testing to date consisted of rolling the throttle on in 5th gear down my local expressway.
Boost pressure would build smoothly to 14-16 psi until I had to back off due to ahem....social conformity issues.
Whenever I got on it in the lower gears it would keep rising, all the way to 22 psi.
It behaved similar to a clutch slipping and that's what I feared was happening.
So yesterday I backed the boost controller all the way out and boost conditions did not change.
It's clear now that the waste gate is staying shut and the controller is having no effect.
22 psi is where the BOV is opening and acceleration is impeded.
When I sent the turbo out for rebuild I just assumed he had tested the actuator. Perhaps not.
I'm going to hook up a compressed air source and try to get the actuator to move.


On the other front I got my 900 cases back from the machine shop.
I had them drill the crankshaft oil passage to accept the Turbo's oil feed to the turbocharger (red circle)
I pressure washed the cases yesterday, still not sure if I'm going to sandblast and paint as most of the areas that show are still good.
It's funny that the boss for this is present on most of the XJ's.
The boss on the cylinder block for the Turbo's knock sensor is also cast into most of them.

 

It's perfectly sensable to do that. Making the engine cases essentially be universal at the casting stage means you can make large single-runs for your working stock, instead of having to make a special small-run for that one model that needs those ports to be machined. Save a few cents per part, and you just increased profits significantlly. The change to the castings was likely done while the turbo was still in the on-paper development stage since those changes are not going to impact anything negatively.

 

I can fully recommend the 16” wheel configuration for these 650Secas if your not worried about original appearance. The handling is much improved, I’m having as much fun in the corners as I am boosting down the highway. Very stable bike.
The Bridgestone Battlax work good

 

I like to think Yamaha was planning to T/C their entire line.LOL
Interesting that both these bosses are tapped for tapered threads.
That’s why I had them done by the machine shop I’m sure the tapered tap would have cost me what he charged for the job.
I’ve never encountered any other tapered threads on a Yamaha.
I understand why they’re used as steam fitting is part of what I do it’s just not common on oil fittings. Rubber O-rings are better.

 

I stripped the pipes off and I can just barely get a look at the wastegate lever with the turbocharger still installed.
I put compressed air to the air line coming from the boost controller and verified the lever was moving.
I can't tell how much pressure I applied so I'm going to need a more accurate means here.
The actuator is supposed to stroke with just 8 psi.
I'll get my son to help, my 88 yo father hadn't a clue what I was telling him while laying under the bike LOL.
So the wastegate does open, just need to measure when.

 

I hooked up a cheap pressure regulator and managed to feed a consistent 10 psi signal and the actuator is definitely stroking the waste gate lever.

Now I need to verify my boost controller is working properly.

 

You can see how tight the space where the actuator sits.

 

Still trying to sort out why I'm not able to limit my boost pressure.
I bench tested the boost controller, its a very simple device with a ball, spring and a screw to preload the spring to the desired pressure, essentially an adjustable check valve.
I thought it would hold pressure until the spring succumbed then release pressure through the outlet (the outlet triggers the waste gate)
With preload all the way in it holds no pressure, as you can see in the pic 1 psi leaks through it.
I'm not sure if this is normal, still doesn't explain why I'm getting so much boost.

I reverified the wastegate is stroking pretty close to where the stock actuator is supposed to open.
Also verified there isn't a dead mouse plugging the waste gate silencer.
????

 

I took the boost controller right out of the circuit and ran the bike just as they came from the factory in 1982 without the power-up kit.
It worked perfectly, limiting boost to about 8 psi, happy things are making sense now.
Even at 8 pounds it's still a crazy fast bike!

I noticed the boost controller passes pressure out the threads when I had it on the bench.
Perhaps too much leakage there is not holding the waste gate open.

 

That could very well be. It's also possible that small pits have formed on the sealing surfaces. Is it possible for you to disassemble and polish the seat for the ball bearing, along with the mounting surfaces for the controller?
Also inspect the bearing under a magnyfing glass. Even though they are hard chromed bearings can develop ridges over time that prevent s good seal from forming.
As for the threads, I'd seal them with teflon tape. That should prevent the leakage you see there.

 

It's a ball bearing and the seat looks fine. Even if it leaked I'm getting 20 pounds of boost and that should depress that spring and bleed pressure through to the waste gate.
Holding high boost pressure is not the problem.

I don't think teflon is going to fit on these threads, teflon is good to crank threads until you have a tight seal, not for something which needs to be adjustable like this.
There's actually a very small hole in the centre of the cap holding the spring in which leaks pressure so the threads leaking is not going to matter.
I found this on the net and they talk about controlled leakage. I get that it's going to take testing to find the sweet spot but I've already had it adjusted as soft as it will go and still seeing 22 psi.

Ball-and-spring controllers: Later, more sophisticated ways of fooling that wastegate were introduced, like manual boost controllers that, internally, were made up of a spring-loaded steel ball that created its own controlled leak between the boost source and the wastegate. Boost controllers like these still bleed off boost pressure but are known for their ability to increase lower-end performance and turbo spool-up since they're able to hold that wastegate valve shut until the last moment. Adjustments can be made by cranking on a knob that stiffens the spring, which means more boost will be required to move that ball out of the way.
Manual boost controllers like these are known for their simplicity and ability to crack open the wastegate's control valve at the last possible moment. Their main disadvantage is they don't offer on-the-fly adjustability and that finding that target boost level is a process of trial and error.

 

Here is some info from the manufacturer about the hole I saw in the cap.

Centered Vent port
A small detail that makes the BoostValve better than many of the other boost controller designs. This allows it to release air trapped in the waste-gate line after turbo boost pressure drops. Many hours of testing led us to the correct port size.

 

as you can see it's a pretty simple device.
The BoostValve is probably mid-priced, they seem to range from $10 to $120

 

I was thinking about my comments more after recalling how my automatic brake bleeder works. It's essentially the same sytem, but at lower pressures. I think you are on the right track to getting her to run how you want.