i have a 1 3/4 SU on my 1275, we are currently having trouble tuning it. i was wondering what is the correct/best size needle for this, as i think it could be the wrong 1 in it.

Cheers

Rohan

_________________
1964 MORRIS 850 - POST ZOMBIE APOCALYPSE CAFE RACER INSPIRED.

https://spotify.link/D0P4KtIP2yb

1098 +0.40
266 Kent Cam
GR Flat top pistons
HS6
1.3:1 Roller tip rockers
Stupid high CR

I think a tuner would need to know a bit more - head work? Valve sizes? Cam Grind? etc etc.

I'm sure a few guys on here could get you close, but you'd really need a dyno run or at least a blast up the street with a gas analyser to get it spot on I'd think.

_________________
Bob Slattery
Duffman Says A Lot of Things - OH YEAH!!

From experience messing with needles can be damn frustrating, and what works for one may not work for another.

Trial and error is a good way of finding what works in YOUR motor, but then you need at least a few needles to choose from.

_________________
Website: www.justanothermini.com

Yep I Agree also with the above

You can also give midel a call..sorry i don't have the number at work but check them up on the net and ask for Silvo

_________________
Stop Licking the Dog...I Don't Care Who Started It

Before you run out and buy sets of needles - what exactly is happening. ??????

What carby is it ?? HS type or a HIF. ??

I have been down the road with both types of carbies on a 1275 and have had to sort problems on both

Basically, my dad is a mechanic and the needle was to big,
He filed it down a bit, it was near spot on then he got a bit carried away and took abit much off, so now we need a new one, i dont know what size was in there to start with, is there anyway of being able to tell just by looking at the needle? is there a part number or size stamped into them?

how do i tell if it is a HIF or HS?


Cheers

Rohan

_________________
1964 MORRIS 850 - POST ZOMBIE APOCALYPSE CAFE RACER INSPIRED.

https://spotify.link/D0P4KtIP2yb

1098 +0.40
266 Kent Cam
GR Flat top pistons
HS6
1.3:1 Roller tip rockers
Stupid high CR

Removed the needle from the carb and have a look on the shank it will give you number or letters for eg BCE is what was on Mine I am now running a BDL. A HS carb is one that you adjust the mixture with a large nut at the bottm of the carb and a HIF is one you adjuste using a screw driver on the side of the carb.
I hope this helps

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I've Got One
You've Got One
We've All Got One
What Is It



A Bloody Mini

1970 Mini K, 1380cc, 1.75 HIF SU, 30 70 Cam, 2" Zorts
1969 Mini K, Stock Standard and Orginal. (Slow as Hell)

ok so it is a HS i know that much

Rohan

_________________
1964 MORRIS 850 - POST ZOMBIE APOCALYPSE CAFE RACER INSPIRED.

https://spotify.link/D0P4KtIP2yb

1098 +0.40
266 Kent Cam
GR Flat top pistons
HS6
1.3:1 Roller tip rockers
Stupid high CR

Okay - now we can get somewhere.
As you say it is a HS type carby, then the needle is easy to remove. Simply remove the outer bell and then the piston. On the lower side of the piston there is a screw that you need to remove and the needle assembly should slide out. The needle is sitting in a little cup thing and is supported by a spring so that it can be a self centering type of needle. It may need a short soak in carby cleaner to come out cleanly - do not grab it with a pair of pliers as you will only do damage. The needle size is stamped up on the thicker neck of the needle. It will be BCE or BDL or something similar.

Now apart from spindle and needle and seat wear which will need attention to ge the carby to run properly, the 1.75 inch HS carby came in a couple of different types and from different vehicles. The angle of the fuel bowl varies and if you simply re tilt it to suit a mini manifold then you make the fuel level higher than the needle and seat and raw fuel flows into the carby. Beware that you have the a carby and fuel bowl that were design to be on 15 degree (or what ever the correct angle is) and that the fuel bowl is the right height.

Having said all that the 1.75 SU is a good carby on a 1275.
Hope that helps.

Yep Look fr the letters on the top part of the shaft, Where it goes into the piston.
Midel contact details 02:9759 5598 Bill Sivertsen (Silvo)
I recomend him
but do have your specs ready..Head work Cam Bore and what size your current neddle is

_________________
Stop Licking the Dog...I Don't Care Who Started It