My '82 XJ750 "Project Shadow Warrior"

You type too much :lol:

I like that color scheme best myself. It reminds me of this
Rick Hunter rocks!

 

I have a lot of time on my hands (when I'm feeling well enough lol)

 

any updates?

 

Update: I've been trying to get this beast to run with no success. Microsquirt is becoming quite difficult. I'm having a more concerning problem with the starter clutch grinding when I turn it over. It's pretty bad. I used Yamalube semi-synthetic oil & I think that might be the problem or a bad starter clutch? I drained the oil and refilled with conventional oil. The problem still is bad. Do you have to Change the oil several times to reverse the effect? The problem is that, I bought this engine without know the history on it. I don't know if it was the wrong oil or if it's the clutch? I might have to go out and buy another engine? Don't really want to do that, but it might be easier than a total breakdown & rebuild?

I have a good connection from the pc to the ecu. I'm having a hard time finding trigger impulse and timing when the starter clutch grinds after 1-2 seconds, very frustrating!

I'm fabricating a flush-mount gas cap from a Ducati Monster. I also just finished my tail reinforcement. It's strong as steel now.

 

The beast Lives!

youtube video of bike running

 

Super cool concept
Would love that front end and that undertail!

 

First test drive. Rev to 4000 rpm. It's not a great vid. I did it one handed with my phone, but I got it one the road! I need a lot more tuning. The ignition table is off in the mid rpm and my AFR is around 11.5 at idle.

Video of first road test!

 

I just uploaded a new video of the bike from a roadside perspective.

Drive by video

 

I friggin love it!
Thats a really brutal bike!

Now paint it already!!!

 

Awesome project.

You should put a link to your build thread(s) on the youtube page though so people can circle back to see more details.

 

That's a great idea! I need to do that.

 

This microsquirt is amazing and the tuning is infinite! Once you have an understanding, this is an incredible tool! You are no longer stuck with factory ignition setup. You can change anything in the engine and then just reprogram the ecu to the new setup. You can now reach the full potential of the engine that was once impractical. You can controll other things like boost for turbo or even nitrous oxide setup. I have my ecu turning on my headlight when it sees idle to save battery drain. If you want to learn and have the money/time, get yourself a microsquirt!

 

I have been contemplating this idea for a bit and now after seeing what farmer has done with his bike, I want to turbo! I have the XJ900 engine and I think it will be a real screamer.I hear the 900 lower emd shares a lot parts with the xj600 turbo. I'll need the oil pan from the turbo for the oil plumbing. I'm not sure if they share the same oil pump or should I get a turbo oil pump? I've been looking at turbos online and not really sure what size of turbo to go with? I went to the Garrett turbo website and looked at their turbos and thought maybe a gt20 series would be a good one? I liked the gt25 series because it's small and has ball bearings. Farmer said he had a gt25, but thought it was too big. With mine being a 900(853cc) engine, would it still be too big? I would move the oil cooler to the back of the engine in front of the swing arm at an angle to catch the under draft. I might modify the sandwich plate on the oil filter to accept "AN" fittings and make some custom lines back to the oil cooler. My goal is 150-175 hp, if not more. I'm starting with 97 hp stock. I have Fuel injection and electronic ignition. What do you guys think? Any opinions on turbo size for the 900 or any other parts/ mods to engine?

 

1st of all I love your build on the XJ! I am looking at doing something like that in the future!

With turbo I think you should go for the gt25 series as it has ball bearings! the turbo in my car has no ball bearings and went to sh!t!

keep us posted mate!

 

I've been cramming lately on the turbo idea and learning a lot. I've been scratching my head as to how to feed and return oil to the turbo? The xj650 turbo has an oil pan with a oil fitting mount. Is that for the oil return? I've read that you want the oil return above the oil level in the pan? Where can I tap for oil to feed the turbo? Do I put a tee on the oil cooler line and supply it from there or is there another source on the bike to tap from? The turbo needs to drain then oil by gravity and should not be below the oil return. I guess you need to be able to pump the oil out if it is? Could anyone shed some light on this for me, specific to the XJ bikes?

I'm still not sure on what turbo to go with? I think the T25 will only start to spin around 8,000 rpm at my estimation. The gt2052 seems like a good candidate with the compressor map. It's a journal, but I don't know of a smaller ball bearing turbo than the gt25?

 

I've been watching your build on youtube, here and the streetfighter forum.

After seeing everything you've achieved so far I'm sure you can work out a turbo.

But if that turbo is only starting at 8,000 forget it, there must be something small enough to spin from 6,000.

I would love a turbo on my XJ750 Cafe Racer but couldn't afford it, plus I would be uninsurable.

 

Great effort,
I would say your best bet is to get a manual for the XJ turbo bikes and use it as a baseline to reverse engineer a solution for your application. There will be improvements to make. I wish I had turbo bike knowledge to share with you but I do not in this application.
Have you considered supercharging? You can buy a rotrex viscdrive derived supercharger, bolt it on, tap the crankshaft, shove the intake onto the airbox, seal it up and awy you go with the megasquirt for control.
Fitting a SC and maybe a FMIC on there will be a challenge to your aesthetics.....
The other consideration is the lower compression ratios of forced induction bikes, If you're only planning on running low boost then maybe not such an issue but higher compression (relatively) motors won't take too kindly to high boost applications. Traditionally, one would aim to do some head work or change stroke to lower CR before applying forced induction. Superchargers aren't laggy like turbos but if you're thinking of correctly matching a small one, this won't be much of an issue anyway.

 

I've been doing some number crunching and bought the turbocharging performance handbook by Jeff Hartman. This is a great book with all the equations needed to design a turbo system. I'm still having some confusion though. It looks as though to get 190-200 hp @ crank, you need almost 20 lbs of boost! This is not going to happen on a road bike. My calculations are this:
air flow requirement
AF= HP x AFR x BSFC/60
AF = actual mass airflow in pounds per min
hp = target flywheel horsepower
AFR = air/fuel ratio
BSFC = brake specific fuel consumption in pounds per horsepower x hour ( /60 to convert hours to min) usually .55/60

I'm taking 150hp into the equation

150 x 11.5 x (.55/60) = 15.8 LB per min of air required

know I need to calculate the manifold pressure required for the air requirement.

MAPreq = (Wa x R x (460 + Tm)) / (VE x (N/2) x Vd)

MAPreq: manifold absolute pressure (psia) required to meet the horsepower target
Wa: AIRFLOWactual (pounds per min)
R: gas content = 639.6
Tm: intake manifold temperature (°F)
VE: Volumetric efficiency
N: engine speed (rpm)
Vd: engine displacement in cubic inches

MAPreq = (15.8 x 639.6) x (460 + 130)) / (.89 x (10,000/2) x 52.05)

MAPreq = 25.74 psia

This is actual pressure. Subtract atmospheric pressure to get gauge pressure (A.K.A. boost)

boost = 25.74 - 14.7 psia (at sea level) = 11.04 lbs of boost

By the way, my engine is a XJ900(52.05 cu.in.). It has a VE of .89 and creates 9.68 of air flow naturally aspirated.

My understanding of boost is that 1 LB of boost creates between 9-10 hp. If that is correct, 11 lbs of boost should be 99 - 110 hp extra? This must not be the case. I also see that by adding up to 11 lbs of boost, I'll effectively have a compression ratio around 11.5:1 from 9.6:1. I think that should be safe with premium fuel(92-93)?
Running that high of boost concerns me as whether I'll need a intercooler or not? There is not much room and I also need a larger oil cooler. The one I have now is not great. There looks to be room in front of the rear tire. I know the factory originally put the turbo there, but I'm looking to stick it in front of the engine like Isaacson06. I might try and fit a oil cooler back there and put a intercooler in front?

I'm throwing a lot of math here, so I hope I don't lose you guys.

My figures came out to 2.02 pressure ratio & 7.9 lb of corrected air flow for max tq @5,00 rpm and around 12 for max hp @9500.

I'm still not confident in these figures and need to bounce them off someone. I called Mr.turbo in TX and they told me they wouldn't be able to talk to me for at least 2 weeks! Garret turbo won't return my emails and other companies aren't helpful. I looked on garrett turbo website and found that the gt2052 (2) turbo map looks like it might be the right one but I might be way off? I could really use someone with experience here.

 

Interesting,
I don't know anything about the book or the author. I guess he must be a very accomplished engine builder. However, it seems that these equations are a bit rounded rather than specific. Your calculations check out for the numbers you have used.

is R the gas content or gas constant?
Using ball park figures is good for a generic understanding but be wary for specific design like the one you are undertaking, by using ball park figures you risk either being disappointed with your final HP output or buying a mismatched turbo that cooks it.
I would always go for an intercooler if i were going for a high boost application/ and or its possible to fit, but have a bike running without one and just an uprated 2nd oil cooler. I run just 9psi of boost max but have more ccs and a lower CR to start with (8.8ish). I've found on hot (100F plus) days in traffic, the beast can overheat and i have to keep an eye on coolant levels.
Regarding octane, i never go less than 98 RON, although it will run ok on 95 (same as your 93 AKI). The high octane pump fuel in Europe is higher than in the US and Aus so its less of an issue but you can always drop in some booster to each tank. You wouldn't want to be hitting high boost with lower octane in too much, but its ok for normal road riding.
Intercoolers don't typically increase horsepower as we may calculate (cooler air=denser charge= more fuel burn=more power.... in theory), but they guarantee it for a given ambient temperature and they also add a safety factor to the engine.
Looking at the Compressor map with the numbers you have, aren't you a bit on the edge with the 50 trim?

If you just want info then these guys are some of the best
http://www.turbotechnics.com/
in the UK, so you won't necessarily want to buy from them but they have always been good at getting back to me. Pop them a mail or call if you can deal with the accents.

Great effort for getting on this, I'll be watching the progress with interest.

 

Have you seen the garrett boost advisor.
Great tool. It basically does all those calcs for you in a very gourmet application
http://www.turbobygarrett.com/turbobygarrett/webadviser
It comes up with the same unit you have displayed the map for, above.
I'd go with the smaller trim 48 to keep the mid range away from the surge line.
Anyway, the point is, you should have more confidence in your calcs.
Have you looked at KKK, perkins etc. they may have other options although the specs will be identical but the packages may be cheaper new and 2nd hand.