Bike build: air gas hybrid

[JB848]

Humm I thought about this and Bullet Proof just didn't seem right to me. "Kojak" Tellie Savales?

[saxman]

Humm I thought about this and Bullet Proof just didn't seem right to me. "Kojak" Tellie Savales?

I would never actually call it bullet proof... none of the kevlar will ever be visible either, so it really wouldn't make much sense

[saxman]

SV650 throttle bodies showed up today. Now I get to disassemble, and find a way to make two into one... i.e. the sensors from each on only one throttle body.

These are way nicer than the gsxr units I was going to use, and have all the sensors I though I was going to have to fabricate mounts and such for, etc.

WAY larger too... which means they won't bolt up quite as easily, but that's ok, I'll just mill out some adapter plates.

[saxman]

sv throttle bodies unwrapped


One torn down, with the gsxr throttle cable pulley attached (the other sv throttle body is the one with the cable pulley mounted). Secondary butterflies removed, secondary tps pulled.

Going to need to drill out a couple mounts for the fast idle valve and machine some spacers, but not that big of a deal. Also going to have to machine an adapter plate for the throttle body for the gs motor, but again, nothing major.

Amazing how much large than the gsxr throttle body (on the right in the pic) the sv unit is. Makes sense though... has to feed 325 cc instead of 125cc on the bike.

[aaronjosephward]

have you decided what you're going to use for engine management?

[saxman]

have you decided what you're going to use for engine management?

Running a megasquirt ecu I built

[saxman]

My christmas present, ready to open this morning


Had to fight with the damn thing for an hour to get the tank out... but when I did...

Fresh from the mold




Kevlar lined

And the money shot:

[saxman]

Now with more gas cap

[dohabee]

That is really cool! Do you have the bottom on it yet?

I wonder what the difference in weight between yours and the stock  tank is?

[saxman]

I have a decent amount of work to do before I'm ready to attach the bottom to it.  I did test fit and it fits great though.

The top half of the tank, with the gas cap weighs 2.2 lbs. Before adding the fuel pump, it'll probably weigh in around 5 lbs when all is said and done.

[saxman]

I originally purchases a set of throttle bodies from a GSXR600 to use for this project. I paid next to nothing for them because of some damage they had suffered. Unfortunately, the lacked some key components as well; most importantly, a fast idle valve, used to control the idle and air flow to the motor during warm up. After working with them for some time, I decided to go another route, and picked up a set of throttle bodies from an 03+ Suzuki SV650S. These throttle bodies are much larger in size, so there should be no question about them supporting the motor, they include all of the sensors I could need, and are better set up for running as individuals.


Unfortunately, there are 2 throttle bodies here, with the sensors and valves needed split between them. For the bike, I need one throttle body that has the throttle plate to attach to the hand controls, the throttle position sensor, and the fast idle valve. To do this, I've taken the throttle body with the tps sensor attached, removed the throttle plate from the gsxr600 throttle bodies I was going to use, and modified it to work.

Here is the SV650 throttle body(left) next to the much smaller gsxr600 throttle body(right), with this modification already finished.


The fast idle valve will attach to the left side of the SV650 throttle body. To do this, I just need to drill out and tap two holes, create some spacers on the lathe, and bolt it up. An adapter plate to mount the throttle body to the motor will also be needed, however, none of this is a significant undertaking. Between this and the nearly finished gas tank, the fuel and ignition system for the bike is almost finished.

[Paulcet]

Very nice work! 

[saxman]

Very nice work! 

Thanks. Popping the tank out of the mold was really nerve racking. So glad it worked out.

[saxman]

the second generation sv650 intake manifold boots happen to bolt right up to my GS motor... Going to save me a bit of machining.




Much better with the new throttle body

[skirecs]

did you take out the valves so they are always open and you get a pump stroke every revolution?

and is there going to be a pressure tank somewhere to smooth the intake pressure?

do you have mass air flow sensor with pressure for that megasquirt controller

[saxman]

did you take out the valves so they are always open and you get a pump stroke every revolution?

and is there going to be a pressure tank somewhere to smooth the intake pressure?

do you have mass air flow sensor with pressure for that megasquirt controller

Yes, the stock valves were removed on the side of the motor that's acting as a compressor.

Bit more details on page 2 of this thread if you're curious.

There will be a pressure tank before the throttle body. I may actually use an intercooler as my pressure tank so I can get air storage and cooling all in one.


I'll be using a map sensor instead of a maf sensor. Easier to set up and I've done a lot of tuning in the past with turbo motors running map sensors, so I'm more familiar with it.

[redhenracing2]

Your valves on the combustion half are ugly.

[saxman]

Your valves on the combustion half are ugly.

Busted motor that's just being used for fabrication of parts.

[redhenracing2]

Ahh. I should have known better, with it being your quality work at hand.

[saxman]

I've got 3 GS motors sitting in the garage. No way I'd want to have that head anywhere near my bike