MicroSquirt.com read only forum (Jan.15,2018)

mikesb wrote:There doesn't seem to be anyplace to mount a fuel pressure regulator on the fuel rail. Where is it normally on these things?

The GSX-R fuel pumps have the fuel pressure regulator built into it. The regulator dumps any excess fuel straight back into the tank.

Which makes for much simpler plumbing, as you only need to run one fuel line.

This is a GREAT THREAD! Thanks for posting this stuff all in one place, very helpful.

I have a small correction for the Kawasaki GPz1100 TB's

The spacing is actually 77-97-77mm NOT 80-100-80. Only DOHC Honda CB Supersports (79-83) used the oddball 80-100-80 spacing.

I also have a question about the GSXR600 38mm TB's. I am installing a set of these on my bike. Do you have confirmation on the 240cc/45psi figures? Do you know the stock pressure? Thx

Also re another discussion of these bodies. On the Keihin corporate website, they describe the ecu controlled TB's as a way to meet tough emissions standards. There is probably little value in preserving the system if you are building a performance vehicle. Restriction of air will not give better torque, it is just a way to burn less fuel...and keep the front wheel on the ground during roll-ons!

Cheers!

Chris

chris900f wrote: I have a small correction for the Kawasaki GPz1100 TB's
The spacing is actually 77-97-77mm NOT 80-100-80......

Thanks, the spec´s are updated.

I also have a question about the GSXR600 38mm TB's. I am installing a set of these on my bike. Do you have confirmation on the 240cc/45psi figures? Do you know the stock pressure? Thx

No confirmation yet, tried both Keihin and Suzuki for spec´s but with no luck.
Should be abel to measure my injectors in a few week if all goes well.
I have read 43.5 psi as stockpreassur on a GSXR750 but can´t remember where I found that info.

Also re another discussion of these bodies. On the Keihin corporate website, they describe the ecu controlled TB's as a way to meet tough emissions standards. There is probably little value in preserving the system if you are building a performance vehicle. Restriction of air will not give better torque, it is just a way to burn less fuel...and keep the front wheel on the ground during roll-ons!

Seems like Suzuki use the sec. throttle for better low rpm respons but as I binned them I´ll try not to run on low rpm so much instead.

@exupturbo

where do your 46mm throttlebodies come from?

thanks

16V-Sauger wrote:@exupturbo

where do your 46mm throttlebodies come from?

thanks

I believe he got them off a 98 - 99 GSXR750.

spag wrote:Waxstat... I didn't spot that, is that the thing I think is a vac jobby, with 2 hose fittings on the end ??

Oooo, just taken it to bits, and yep it's a waxstat.

With all the other vac plumbing I got confused.

Easy for the cold/warm idle thing, but not so good for idle control - sorry

bizarre but true on the CB (Honda Hornets ie non CBR) the air bleed is operated by a cable attched to what in effect is a 'choke' cable on the handle bars..

I have some 36mm bodies from a CB919 Hornet fitted and running on my Imp engine.





Si

Make/Model: CBR 954 Fireblade
Year: 2003
Number of Tb: 2
Inside Diameter: Tapers from 45-41mm
Center-Center (left to right from behind): 80-80-80
Overall Length: 77mm
Outside Diameter (intake): 50mm
Outside Diameter (filter):
Separate casting: No (dual Tb´s)
Injector Make/Model: Denso 12 226 4490 I suspect the 226 is cc/min, as the bike is good for 150hp... 13.3 ohms
Flow Rate (45psi/100%): ?? (Std fuel pressure on bike is 50psi)
Fuel Rail Inside Diameter:
Additional Info: Factory couplers need to be used as inside diameter is offset and not a perfect circle.

I have GSXR1000 42MM throttle bodies on a ST170 inlet manifold.

Not 100% complete yet, just a bit of bonding to do.


Asad

Details of the mods to make them fit the ST170 Manifold are on my site:
http://www.mez.co.uk/ms10.html

Asad, I'm partial to the odd pint of speckled hen

Marcus wrote:Make/Model: GSXR750
Year: -98, -99
Number of Tb: 4
Inside Diameter: 46mm
Center-Center (left to right from behind): 80-80-80mm
Overall Length: 91mm
Outside Diameter (intake): 54mm
Outside Diameter (filter): 54mm
Separate casting: Yes
Injector Make/Model: Keihin,
Flow Rate (45psi/100%): 240cc
Fuel Rail Inside Diameter:
Additional Info: No sec. throttles.

I have it from a reasonably knowledgible source that this is the only setup that does not have "vacuum operated secondary throttles" behind the driver operated main throttles. Does anyone have any information about this? I'd like to find out more about how these secondary throttles work.
According to the specs posted, these also seem to be the biggest throttles around as well.