GS1000G mods- big bore and fuel injection

[GS1000G Shopper]

I now have the 1100G head & cylinder and a set of GSXR600 intake boots. The throttle bodies will be here later this week.

Preliminary work shows the 1100G intake boots will be way too small to fit the throttle bodies. The good news is that the GSXR boots almost bolt onto the head. A little work with a small round file and they will bolt down. The head side of these are oval, so a little porting will be needed to get them lined up so there is no restriction. I have some pics and will post them later.

I found a good write up here where a set of the GSXR600 throttle bodies were installed onto a 16V GS engine. He links to here, so he is or was a member at some point. It was never completed since 2009, so hopefully I can go further than he did. One thing I noticed was he used the 1100 boots. I think what I have in mind will be easier to do, and will hopefully allow for some flexibility on the installation where he ran into some problems.

The items he mentioned needing like the long 6mm bolts can be replaced by stainless all thread for < $5 at McMaster-Carr, and they also sell 6mm x 10mm x 13mm aluminum spacers for <$1. He specified 6mm x 10mm x 14mm, but 1mm there won't make a difference from what I can see (see update below). I have some ideas for the fuel rail also, but will need to have it in hand first.

UPDATE
When I lined the TBs up for use of the center linkage, I found a 6mm ID x 13mm OD x 19m (3/4") wide spacer would be a better fit. The McMaster PN is 94669A949.

[GS1000G Shopper]

Here are the pictures of the boots on the 1100G head. By an error, I also ended up with a set from a 2002 GSXR750. They are larger in every respect, but bolt on as-is with no filing. The GSXR600 boots are the better fit for the port.

One GSXR600 boot- a pretty close fit to the port:


GSXR750 boot- note the extra aluminum visible in the port:


All 4 600 boots installed:

[GS1000G Shopper]

$89.99 on Amazon.

I looked for the GSL414 pump there by keyword and only found a 255 lph GSL392. Do you by chance have a link or item #/more info?

[tkent02]

I put in Walbro GSL414 and it comes up with GSL392

Sorry I didn't look at it that closely the other night.

[GS1000G Shopper]

UDATE- I ended up using the center linkage shown on the table of contents. The longer cable worked OK, so the shorter one should do so as well.
I continue to be amazed at how the Japanese build (or built) stuff. Today I received the GSXR600 throttle bodies and Hayabusa controls. As expected, the outer throttle bodies will fit right into the GSXR600 boots, but the distance between the middle ones will need to be increased.

The cool thing I discovered is my single throttle cable GS1000G control will interchange 100% with the 2007 Hayabusa dual cable control. The 1000G throttle tube has two cable openings in it. The new cables are way too short, but this is where the cool factor increases. The cable from my G will screw into the newer control, and I can use the G throttle tube as well. The Hayabusa stuff is a little crusty and laid out slightly different than the late model ones (like I just put on the GSX-G project), so I'm replacing the controls with some from a 2007 GSXR 600. Plus, the Hayabusa has a choke function I won't need.

Here are some pics from today:
Throttle body test fit:


Close up of outer units:


Hayabusa controls:


SFV650 control on Hayabusa tube & bar:


Hayabusa control, GS1000G tube & throttle cable on GS1000G (worked perfectly for throttle movement):

[tkent02]

Looks like you only need to adjust the length of the fuel rail? Or is there more?

[GS1000G Shopper]

From my preliminary disassembly of the units and some measuring with them sitting in place, at least three things will need to be done:
1. Insert 19mm wide spacers where the long 6mm bolts go through. (McMaster sells these) (updated from 12-13mm to 19m 6/13/15)
2. Extend the throttle connection from the #3 to #2 throttle body. (Update: welded a 3/8" block onto the #3 TB)
3. Extend the fuel rail. Since I want to add a pressure regulator to the other end, I will likely cut it and see if the interior is round or oblong. If it is round, and based on the plug in the far end it is, I can slip in some aluminum tubing and have it welded so the proper spacing is achieved. Update: Cut it and drilled the openings to 3/8 and brazed in some 3/8" OD aluminum fuel line.

The fuel inlet fitting is similar to the late model GM fuel injected cars I've worked on- it is a plastic clip over a metal nozzle, and a plastic fitting on the inlet hose. I know Summit sells adapters for these to AN fittings.

EDIT
I forgot to add the secondary throttle shaft holes, which must be sealed. The quick & easy way here is to just tap them for 1/8 pipe- no drilling required as they are just shy of 3/8" in diameter. They can then be plugged with pipe plugs.

I have some more pics for some of this and will upload them later.

[GS1000G Shopper]

More pictures:
Fuel inlet fitting with hose removed:


Throttle body tab gap:


Spacer gap: UPDATE- I used a 19mm wide spacer after using the center linkage setup.


Test fit:

[GS1000G Shopper]

Fuel rail cut in half, inner diameter is about 1/4".
UPDATE:
I originally had used 3/8 OD fuel line and JB Weld but rethought this. I ended up using the same 3/8" aluminum fuel line that has a .245" ID. I drilled out the halves of the rail to 3/8" and then brazed the line into them.

These should allow the TB units to be seated and spaced properly.

[GS1000G Shopper]

UPDATE- Avoided this tab extension by using coombehouse's center linkage with my mod. When I removed the throttle plate it never realigned properly, and I believe this caused the high idle when I started the bike. The center linkage is a better way to accomplish this task.

While I had the rail off, I drilled out the brass plug on the far end. The opening is just slightly larger than 7/16, so it threaded as-is for 1/4 pipe. In the picture below, I have a 90 degree pipe adapter in it. I'll plumb the pressure gauge here.

1/4 pipe fitting at end of rail:

[ArttuH]

It's advisable to have a filter between the pump and injectors. It's not a bad idea have some kind coarse pre-filter on intake side of the pump too but probably the screen in the tank is enough for that. The filter before injectors should be "injection grade" i.e. fine filter, less than 10 microns.

[gmansyz]

Note

A small comment. I like what you did with everything only, why not see if you could wedge the GSXR TB's into the stock GS1100 intake booties? They may be, at the most 2mm bigger than the 34mm cv carbs are but I believe, as I do have a set of them as well, that maybe only 1 to 1.5 mm bigger. Arttu used the same ones on his GS1100.
Laters
Greg

[GS1000G Shopper]

As difficult as it would be with the head fully accessible, trying to wedge them on after it was installed would be really difficult. I'd rather spend some time with a file (boot) and Dremel (intake) and have something that is easy to maintain. I have a big chip on my shoulder as far as carb installations go- anyone that has had to do this on an 80's V4 Honda engine can likely relate.

I've observed many a time in working on vehicles that the people that design them never work on them (the Sabre and my Gen 4 Trans Am are outstanding examples), so when I am designing something, maintenance is always in mind. The fewer battles there are to fight doing routine work the better.

That's why.

[GS1000G Shopper]

It's advisable to have a filter between the pump and injectors. It's not a bad idea have some kind coarse pre-filter on intake side of the pump too but probably the screen in the tank is enough for that. The filter before injectors should be "injection grade" i.e. fine filter, less than 10 microns.

Thanks, I'll look into it. I originally had an AN6 filter inline but it occurred to me I could use a barb one since the suction side does not need the expensive fittings. The GSX-G uses just those screens as its sole filtration system, and I've added an inline filter before & after the pump. I need to look at the GSXR-600 and see what it does.

[GS1000G Shopper]

Pulled the tank today. Preliminary sizing shows the GS1000G petcock and GSX1100G tank fittings are the same size for mounting. It looks like I may be able to use the GSX-G tank fitting. For the return side it has a long brass tube and also a small screen at the lowest level for the supply side. There will be no reserve function, but that is what a gas gauge and trip odometer are for, right?

Pics will follow if this is viable.