Pictures and videos of my fuel injected 1978 XS1100

[Snow]

I just won my 2003 GSXR600 Throttle bodies for $70 including shipping This Christmas, I get the computer parts.

[sksxs1100]

What did you use for a tach signal and how did you hook up a coolant temp sensor?

[Bill]

Dan "mainlylinux" Mann wrote:

The throttle cable is the hardest part - the gixxer throttle bodies have a connector that is very different than the yamaha one. Gixxer throttle cables are to short to use as is, so I've cut one in half and I'm going to lengthen it.

I don't know about throttle cables on late-model GSX-Rs, but a long one for my '87 GSX-R1100 was easy. When I put on some standard handlebars, I used a throttle cable from an '80ish Suzuki GS450L (cruiser type, like a Yamaha Special).

The fuel injection computer itself is easy to build, and cheap. There is a manual that can be printed out that explains everything. You need basic hand tools, a soldering iron, some solder, a volt ohm meter, and some patience.

In your pictures I noticed an oscilloscope and some other special equipment. Is this necessary, or just handy?

I'd love to try this on my '87 GSX-R... and I already have the throttle cable!

[mainlylinux]

The oscilliscope was needed because I had a problem with the computer on step 39 - I couldn't get the computer to communicate with my laptop. In the end I solved the problem with a plain old multimeter that I got from Radio Shack for $50. One pin going to the cpu socket had some signal leakage, and it was causing the cpu to go into reset mode. I ended up unsoldering the cpu socket and re-soldering it, and the problem went away.

So now I have a scope if i ever need one; luckily I got the one in the picture off of ebay, and it only ran me $140.

The throttle cable housing is threaded with a nut on one end. That's one of the reason's why a XS cable won't work.

Go for it! I'm sure the gixxer would run great!

Dan

[Bill]

mainlylinux wrote:

The throttle cable housing is threaded with a nut on one end. That's one of the reason's why a XS cable won't work.

That sounds the same as many (most,all?) of the old GS bikes. Some early ones with mechanical carbs (non-CV type) had double push-pull cables.

They list for $10.99 in the Dennis Kirk catalog.

The other end is also a little different from the XS. It threads into the throttle handle instead of being secured by a collar and screw.

There's a good picture of one on eBay:

GS550 Throttle Cable

You could either adapt the cable or use a complete Suzuki unit and adapt the wiring for the start button and kill switch.

I think I paid about $10 on eBay for the whole GS450L throttle and cable. There's one for a GS250 right now on eBay:

1980 Suzuki GS250 Throttle,Cable,Switches

Please keep us posted on your progress!

XSively,

[jacuff1]

Thanks for the links guys! Looks like this should be interesting. I just bought a set of throttle bodies and wiring harness for a GSXR750 off eBay. I'm going to try this first on my Triumph Spitfire. I had already started building a manifold to put a set of Keihen bike carbs on it anyway, and since it's an inline 4cyl. engine, it should lend itself well to experimenting with this system. I went with the larger 750 tb's, since the Spit motor is a 1300. I figure the hp rating will be pretty close. I probably won't use too much of the harness that comes with them, but I figure it would be helpful to have the plugs that match the connectors on the tb's. Now time to start getting the parts to build the Megasquirt.
Wish me luck!

I wonder if the 600 tb's would work with some smaller injectors on my GS550-powered quad?
Vrooom!!!


John

[mainlylinux]

Well, I just ordered my throttle cable from Motion pro. I talked to larry, and he was very helpful. The total cost should be around $38 bucks (including shipping), not bad for adding 32.5 inches to the original gixxer cable!

Jacuff1, lemme know how it goes!


Dan

[Snow]

Wow, my head is swimming with ideas and images and questions - I just read the Deployment Guide Draft from end to end. Firstly, I need to know which MegaSquirt parts I need to order - I think I just need the MegaSquirt partial kit and MegaStim PCB. I noticed that you had 3 different boards and couldn't figure out what the last one was...so what is it?

Where did you get your other components? What about that snazzy plastic-looking black case and part number for case?

I've noticed that it could take just over a month from time you send the check and order form until you receive the parts - I'm hoping to have all the parts necessary around Christmas time so I can work on it during my ...errr... forced timeoff from work, so that means I should send the order out today or tommorow.

In addition, what are you doing about a temp sensor? If this has already been answered, just disregard - I'm about to double check in previous posts.

Also, in regards to the secondary, computer controlled throttle butterflies, did you just simply remove them?

Last question fer now, I swear... it seems that the GSXR throttle controls use a push and a pull cable and you said you ordered one cable - how will that work out? Do you really only need one?

Thanks for all the info

Pete

[Bill]

Pete wrote:

I noticed that you had 3 different boards and couldn't figure out what the last one was...so what is it?

I've been reading most of the same stuff, Pete. The third board is probably the relay board. Dan wrote to me saying, "... you may or may not want the relay board; it isn't required, but it makes things easier. You could definitely live without it. It runs around 30-50 bucks".

I'm also looking at trying this system, but I'm going to watch and wait for awhile.

XSively,

[Snow]

I'm much too impatient to wait and watch My throttle bodies came in and my check+order for the MegaSquirt partial kit and MegaStim went out yesterday. I've been looking around for a nice inline electric fuel pump and I've actually come across a Holley that flows 70 gph at 9psi with 14psi preset regulator for $105.95 from Summit. I'd still need a relay for that pump though.

I took a look at the throttle bodies and it does seem like we could get away with only using a pull throttle cable - is that your plan Dan?

Btw, if anyone has tried to email me through the XS11 board, I never got any - I changed my email address a couple months ago and only just today changed it for the board.

[mainlylinux]

Don't get that fuel pump if it's only rated for 9-14psi, you're gonna need 35-45 psi. Go to you local cheap autoparts store and get an external fuel pump for a '88 ford truck with a fuel injected motor, doesn't matter which one. It should be an inline fuel pump that is rated at the higher pressure rating.

Yeah, my plan is for the pull only throttle cables. As far as the kits go, I got the stim, megasquirt partial, and the relay board. Don't forget you have to order the small components from digikey. You should also read the FAQ and subscribe to the megasquirt list in yahoo groups. that's a great archive to search thru if you have problems.

I found a regulator that should work great, I'll have to get you the part number and what not. you can order it right from summit racing.

You can do without the relay board, but IMHO it makes things easier.

I'll get you the other info you need later today. Had to work late last night and so I just crashed when I got home. Don't worry, I won't forget you!

Dan

[mainlylinux]

here's the fuel pressure regulator that will work...it's relatively cheap compared to some others.

http://www.overboost.com/obs/product.asp?pid=2628

Dan

[Hobbit]

pressure regulation

Mercedes-Benz now uses a fairly simple electronic fuel pressure regulator on the AMG and V12 vehicles. An inline fuel pressure sensor (5volt reference) reports the pressure to the control module which controls the fuel pump by regulating the duty cycle to the pump. This allow the pump to operate at a lower amerage when high demand is not needed.

[mainlylinux]

Thanks for the info! Sounds like that would be a cool setup - I figure it's only a matter of time before we get a returnless fuel system.

Dan

[Hobbit]

pressure

The MB system does require a fuel return line so that the pump is not shuting off completely. However the return can be directed back to the tank anywhere in the fuel line after the pressure sensor and only requires a minimum flow rate.