Z1R Turbo Carburettor

[rpeters]

Can someone tell me what Carburettor I should be using please!

I currently have an S&S shorty installed but cant get the jetting right, what carb should I be using and does anyone have one they want to part with or know where I can get one.

Thanks for any advice

Rob

[zed1015]

With the S&S you will probably be having trouble with an inconsistant and over rich mix which can be improved by the use of some dyno time and the fitting of thunder jets to spread the fuel delivery more evenly throughout the rev range (although the new super G pumper i have on the Drouin supercharger worked fine out of the box)
Most people though will fit a Mikuni HSR42 which is much better suited for the road..
Once i get mine built that's what i'm going to use..

[neilbarrett]

I used to use hsr 45mm .but they were big motors 1425cc&1560cc.aint run s&s for yrs .but they were sound.

[rpeters]

I will try the jetting again first, but the Mikuni is an option.
Also,
I found this in a box at the back of the garage, seem to remember it coming off a turbo bike, looks like some sort of elbow for Thunder Jet type addition, doesn't look like a NOS fogger port. Looks to be all complet

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[zed1015]

That's a 42mm Keihin carb off a Mr Turbo kit.
Had a couple of those, one of which had the same brass elbow which was more likely to be the remains of a water injection set up as it bore no resemblance to a thunderjet or nitrous part.

[rpeters]

Thanks Rob, that's a stroke of luck because I am running a MR Turbo Kit on the Z1R. I will Whip off the shorty on the weekend. Probs best to plug the elbow hole.

[Big Fluff]

I've set up 6 of these now. I spec the following:
Mikuni HSR42 with 4.2mm fuel inlet valve (Part: Mikuni Float Valve Assembly +o-ring 786-27001-4.2), 230 main jet, 30 pilot, 97 jet needle (Part: J8-8DDY01-97) All parts available from Allens Performance. These specs are for UK conditions only.
Pingel fuel tap. You can NOT run a HSR via even a low pressure fuel pump!
S&S Shorty's are horrible in my experience.

[rpeters]

Think I might bow down to proven solution with the Mikuni, thanks Will
Rob

[Big Fluff]

Think I might bow down to proven solution with the Mikuni, thanks Will
Rob

No problem Rob, they really do make the bike so much more rideable, they don't bog down either.
However, I would NOT buy one of those cheap chinese copies... of which are advertised as "For Harley Dav...."
Personally I would buy one from Andy at AFM Motorcycles, he's a great guy to deal with. The HSR42 carbs he sells already have the larger bore fuel inlet valve too, AND the 97 jet needle so all you'll need is a main and pilot jet change. https://www.afbmotorcycles.co.uk/motorc ... r-big-twin

If I can help in any way just give me a shout via messenger on FB.

Best regards, Will

[rpeters]

Wondered why some on eBay are over £400 and some are £140!

[rpeters]

I have a Pingel tap installed already, so I don’t need a pump?
Rob

[neilbarrett]

buy the turbo model one

[Big Fluff]

I have a Pingel tap installed already, so I don’t need a pump?
Rob

Correct, no pump needed, just the large bore fuel inlet valve.
You can't run any pump with a HSR anyway as it will piss out.

[neilbarrett]

I ve run all my hsrs with a facet low pressure pump with a adjustable fuel regulator 2.5psi max as after that the carb will flood on tick over.pump and reg available from demon tweekes

[Big Fluff]

I ve run all my hsrs with a facet low pressure pump with a adjustable fuel regulator 2.5psi max as after that the carb will flood on tick over.pump and reg available from demon tweekes

I've only had luck with running max pressure of 1.5psi and that's also with the smaller fuel valve. The bigger fuel valve will be even more prone to pressure.
One of the problems is that some of the facet fuel pumps from demon tweeks are the pulse type which makes things worse, hence why I say sod it and just use the big bore fuel valve and pingel tap.