Combat Amal carb setup

ILLF8ED · Jan 29, 2021

For the combat owners still using Amal 932, what throttle slide cutaway do you have?
Stock is #3, 230 mains and needle clip in the middle. With this ethanol gas, I’m wondering if that really still works.

ILLF8ED · Jan 29, 2021

Let me know what main jet is working for you also.
Thanks

marshg246 · Jan 29, 2021

If you buy new Premier carbs for stock Combats, Amal supplies:

Main Jet: 220
Needle Jet: 106
Throttle Valve: 3
Needle: Standard
Needle Position: 1
Pilot Jet: 17
Spray Bar: Standard

They work fine. With ethanol, you could go 230 main and needle position 2. I wouldn't go to a different cutaway.

seattle##gs · Jan 29, 2021

How about a #19 pilot?

marshg246 · Jan 29, 2021

seattle##gs said:
How about a #19 pilot?

Amal supplies those for 850s, not 750s. #17 works fine for 750s - 850s really need #19.

baldy · Jan 29, 2021

I ended up with the 19 jet on my combat. Way better.

bill · Jan 29, 2021

Mine is
#3 slide
Needle top notch ( lean)
190 main
This is with non premiers. I find it to rich on the main if i go to a 200. Also i still have the chokes and I usually get 50+ MPG

marshg246 · Jan 29, 2021

baldy said:
I ended up with the 19 jet on my combat. Way better.

Better in what way? How far out are the air screws?

Fast Eddie · Jan 29, 2021

I had to put #19s in my 650 T120...

marshg246 · Jan 29, 2021

Fast Eddie said:
I had to put #19s in my 650 T120...

What symptom and how far out are your air screws? The 70 T120R i just finished starts on the first kick and idles, no choke, and new Premiers with #17 pilot jets.

Fast Eddie · Jan 29, 2021

Horrible without chokes, had to refit them. Even then far from right. Can remember exactly where air screws were, but they were too far in. Still needs chokes even with the #19s. But other than that it’s now really nice.

marshg246 · Jan 29, 2021

Fast Eddie said:
Horrible without chokes, had to refit them. Even then far from right. Can remember exactly where air screws were, but they were too far in. Still needs chokes even with the #19s. But other than that it’s now really nice.

It's always interesting that basically the same bikes need different things. I'm only asking because of that. I've had British bikes since 1966 and I remove the chokes so fast it would make your head spin! Yet, many swear by them so I'm certainly not saying that others are wrong. On pilot jets, as long as my air screws are out 1-1/4 to 1-1/2 turn, IMHO, the pilot jet is correct.

I am certainly not a tuning expert so I'm only saying what Amal supplies and what I do.

Fast Eddie · Jan 29, 2021

Same here Greg, I have always removed the chokes in the past, and would like to on this bike too one day (when I get it back off of my Dad)!

Some of the differences might be floats and / or float height. I have noted with interested that a number of posters on here have reported improvements after replacing the Premier stay up floats with ‘normal’ plastic ones...

marshg246 · Jan 29, 2021

Fast Eddie said:
Some of the differences might be floats and / or float height. I have noted with interested that a number of posters on here have reported improvements after replacing the Premier stay up floats with ‘normal’ plastic ones...

I stick with the StayUp floats, but I make absolutely sure they are set as Amal recommends. The fuel level, within reason, makes little difference anywhere but starting and idle and it makes a big difference there. There is so little vacuum at starting and idle and the fuel must be sucked a long way to get to the air screw and pilot jet that it's a wonder that they work at all!

ILLF8ED · Jan 29, 2021

Appreciate the replies, but I didn’t really get what I was looking for. Bill, 190 mains, really? I may try it as I have them. Since ethanol is lighter than gasoline going larger on the mains makes more logic.

marshg246 · Jan 29, 2021

illf8ed said:
Appreciate the replies, but I didn’t really get what I was looking for. Bill, 190 mains, really? I may try it as I have them. Since ethanol is lighter than gasoline going larger on the mains makes more logic.

See my first reply - pretty sure I answered exactly what you asked.

ILLF8ED · Jan 29, 2021

Hi Greg,

You said “Amal Premier supplies.“. What I’m looking for is first hand experience. Are you running a combat with that jetting and it’s working with E10/E15 fuel?

marshg246 · Jan 29, 2021

illf8ed said:
Hi Greg,

You said “Amal Premier supplies.“. What I’m looking for is first hand experience. Are you running a combat with that jetting and it’s working with E10/E15 fuel?

Followed by my experience with those jets/settings and a recommendation about ethanol.

marshg246 · Jan 29, 2021

To be clear, for my Combat, I run new Amal Premier carbs and Tri-Spark ignition:

Main Jet: 220
Needle Jet: 106
Throttle Valve: 3
Needle: Standard
Needle Position: 2
Pilot Jet: 17
Spray Bar: Standard

I have no where to ride full throttle so I'm not sure, but I would most likely change to a 230 main jet if I did ride wide open or nearly so.

The only gas available here is E10.

Interbak · Jan 30, 2021

illf8ed said:
For the combat owners still using Amal 932, what throttle slide cutaway do you have?
Stock is #3, 230 mains and needle clip in the middle. With this ethanol gas, I’m wondering if that really still works.

Yup, still works with the Sunoco 94 octane, non-ethanol gas available here.

Combat Amal carb setup

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