Amal 932 Carb Swap. Will it worK?

My 72 Combat carbs 932/19-20 with a 220 Main Jet are worn out. (260 main jets were originally in them when I got the bike). I have these good used carbs from my salvaged 73 850 Norton 932/29-30 with a 260 Main Jet in which to replace my worn out ones. I'm going to replace the 260 Main Jet's with the 220 Main Jet's. Will it work?????
Also, could not find any information regarding the Carb Heat Insulator (Combat) manifold to cylinder, where as to putting any type of sealant in case of air leaks. I have new one's, should I put these on dry? The flat surface of these insulators are so smooth I wonder if anything would adhere to it.
Thank you for your replies and advice. Jerry

72 Combat
73 850 Commando ( my salvage bike)
74 850 Commando

travelerjerry said:

My 72 Combat carbs 932/19-20 with a 220 Main Jet are worn out. (260 main jets were originally in them when I got the bike). I have these good used carbs from my salvaged 73 850 Norton 932/29-30 with a 260 Main Jet in which to replace my worn out ones. I'm going to replace the 260 Main Jet's with the 220 Main Jet's. Will it work?????

Click to expand...

I would be inclined to try them as they are with the 260s first.

Do the 29/30 carbs have the stepped spray tubes, as that could influence the jetting? Or do they have the same type spray tubes as the 19-20s? They can be changed if necessary.
The 932/19 & 20 850 carbs would normally have 3.5 cutaway slides instead of the 750's 3 slide cutaways.

travelerjerry said:

Also, could not find any information regarding the Carb Heat Insulator (Combat) manifold to cylinder, where as to putting any type of sealant in case of air leaks. I have new one's, should I put these on dry? The flat surface of these insulators are so smooth I wonder if anything would adhere to it.

Click to expand...

A bit of (silicone?) sealant won't do any harm. And it will probably stick OK.


72 Combat
73 850 Commando ( my salvage bike)
74 850 Commando[/quote]

You also need to use the correct 5-groove needles with the stepped spray tube. It's way too rich otherwise (though it might compensate for the 3.5 slide).

Just wanted to report on the Carb swap. They worked. Had to use the 220 main jet.

72 Norton Combat