Fuel injection options..

[TajMan]

Hey guys,
previous XS11 owner, and it looks like I'm going to be getting another one for next to nothing, trading for a little automotive work.

I'm a custom builder, I still have my old frame and gas tank & seatpan I can use the tank and seat on this new build, I want to build a custom turbo system for it.. [I'm a mitsubishi guy, 1 of the 3000GT VR-4 stock TD04-9B turbos will be the right size]

..anyway.. you know fuel injection is the only way to go to properly set up a turbo system on a 4cyl bike engine like this. There are options, and I've been wanting to build a megasquirt/microsquirt system for a long time now..

I found this thread with fuel injected throttle body sizing from stock EFI motorcycles (for parts donors): http://www.msextra.com/forums/viewtopic.php?f=94&t=6602

Great info, but smallest ones I was seeing there are 37mm off a suzuki gsr400 or a couple 38mm sets.. and stock XS11 carb boots into the cylinder head are 34mm. Custom intake boots into the cylinder head would be the other option, sounds EXTREMELY difficult especially to hold boost pressure.

I found a site http://www.ecotrons.com that offers fuel injection conversion parts for small bike engines. I got an e-mail back from them.
http://www.ecotrons.com/files/ECOTRO...cal%20spec.pdf
"..is the 34mm throttle body with manual stepper motor, each is $150.
Each 248g/min injector[for turbo] is $55

So, looking at $820 in parts cost there for (4) throttle bodies with fuel injectors, brand new. Oh boy.. I wish so badly I could find a way to adapt these parts from a stock fuel injected bike.. I'd like to spend less than $250 for a set of four used throttle bodies/fuel injectors.

Another tentative project on my list I'm all about if I can make it feasible, I can spend lots of time and not excess money.

[IanDMacDonald]

There are many great threads on here regarding FI'd bikes. I bought one in a non-running state from a guy that had a good write-up on here. Still have the throttle bodies laying in my garage. He did not turbo the bike though.

[TajMan]

Ian I am interested if you have any link or info I can read up that build, and I'd be interested in those throttle bodies you have if you can find them!

[DiverRay]

I think the early GSXR600 FI system will fit the XS. I have a set waiting for my next project. I will need to look at the turbo you say will work. I was looking for something that will give me 8 to 10psi boost.

[TajMan]

I'd say it's about the best quality & cheap turbo you can get that's the proper size. TD04 exhaust is small enough that a proper 4-into-turbo manifold with turbo front and center hanging just below the exhaust exits and behind the front wheel.. should spool acceptably, stock internal wastegates are good for 6-8psi boost, and should be an easy 180hp turbo if you're running sufficient boost and race gas/water injection/etc. With little intercooler(s) and an aluminum intake manifold feeding into the 4 throttle bodies. With stock engine internals, I know water injection would be a smart setup you could maintain with.

Pickup the good used turbo for less than $150, and I believe its the VR-4 or Stealth R/T TT's front bank exhaust manifold that is regular steel not cast, so one of those can be cut and flange used to fabricate custom XS11 9b turbo header.

[crazy steve]

Here's a EFI system..... http://www.xs11.com/forum/showthread.php?t=11498

... Sorry, the link in the thread appears to be dead....

[Prothec]

Here's a EFI system..... http://www.xs11.com/forum/showthread.php?t=11498

... Sorry, the link in the thread appears to be dead....

That's a shame. It doesn't appear to be cached anywhere either.
Hopefully someone made a copy or it pops up somewhere again at some point.

[crazy steve]

The one big issue with doing a EFI conversion on a XS is the increased electrical load. The XS alternator is really only just adequate for the stock bike, finding a fuel pump that puts out enough pressure yet doesn't draw too much power seems to have been the sticking point. I would upgrade all the alternator wiring (the stock wiring really should have been one size larger IMO) and look into the 'improved' voltage regulator offered by Geezer (forum name) though his Oregon Motorcycle store.

There has been a couple of EFI conversions done, but they didn't have turbos.

[Prothec]

I found this in http://www.xs11.com/forum/showpost.p...59&postcount=6 on 5/30/2015, so there's hope!

I posted my work on the XS11 forum under fuel modifications, but the web host I was using closed down earlier this year. I'll rework the write-up and make it into an attachment.

I did happen to find I made a complete copy of his website back in 2012, so I can zip it up and send it on request

[TajMan]

PLEASE!
I want a copy of that

I'm looking at a set of early GSXR600 throttle bodies.. they sure look close, how about the center gap? Are they Close enough that people have shaved the stock XS11 rubber intake boots and gotten the set to fit inside all 4?

As for electrical, ahh yes I understand been through this on bikes before.
... have a link for Cy's car alternator conversion?

Another hurdle, but I'm sure I'd run all LED lights and I'd MAKE it work even if other areas suffered.

[Prothec]

I zipped it up and you can download it from here:

http://xs11.planneddigital.com/wp-co...FI-Project.zip

The zip file contains a XJ1100 EFI Project directory that contains the full site rip with all of the images, etc.

[TajMan]

^thanks so much for a copy of that website!

I just wanted to clarify, I know mitsubishi turbos and why I had made my recommendation earlier about the 9b's,

but after more consideration of the 1100cc displacement and the rev-TQ characteristics of that motor (its not a sportbike motor)...

I feel a T15 turbo would be better suited for early spool and low-boost application. That's just an ebay $185 turbo brand new, which should work well!

(make sure to use a restrictor on the oil feed or turbo bearings will leak oil) I figure I could use a little oil pressure from the line/fitting that goes to the cylinder head in factory location, and I'm not sure where best to tap into block maybe for oil return.

I would probably mount turbo lower up front, if it didn't need to be a good 6" above oil level in engine pan at least, so I'll have to find what works.

And I'd be looking for a 6-7psi wastegate instead of 13-14psi

[DiverRay]

You can tap the oil feed on the left side of the case. There is a bolt/plug from the machining that can be replaced with a fitting. I was going to tap the return on the upper case, center almost to the split. On the inside I'll put a shield so the cam chain does not sling the oil up. This is late this winter before I can get started, though....
Also, look into the reed valves used in 2 stroke engines. I was going to put one with an air filter to feed the intake before the turbo spools up. If it's close to the center of the 4, it should keep the turbo lag "feel" down, and the low end feel up.

[Bikes]

What about an 84/85 gpz 740 turbo?.....i see sometimes they come up on CL 4 or 5 hundred dollars....fuel injected, etc...

[TajMan]

You can do better than that/no reason to use that old bike turbo. Its all about flow maps and sizing, nothing from that old bike turbo setup mounts to the XS11 it would all be custom.

Typically if you keep the intake piping as short and efficient as you can, it shouldn't affect the snappiness of the motor, It should free-rev pre-boost just about the same as before. Actually going to the gsxr throttle bodies from the stock carbs will have more of an effect on rev characteristics than adding turbo plumbing, air can still flow past the compressor blades even when the turbo isn't moving.

I see what you're getting at with the 2-stroke reed valves, but honestly its just much more of a hassle to [if you even can] tune your stand-alone EFI for that weird intake/vacuum leak situation.. and would most certainly need to be set up speed-density instead of with an airflow meter.