Amal carburetors

[Marqs1979]

Hey! What is the difference between these two carburetors? the left are labeled 689/90 and the other is labeled 689/228

689/228 is about 8 tenths of a millimeter larger, the only difference I see.
http://forumbilder.se/F8KTO/20160122-184714.jpg

[Klaus]

Oh you've got a jackpot

These carbs are righthand for twin carb heads.
I dont know what the numbers say but 689 is right hand and 389 is left hand.
They are hard to find.


Cheers Klaus

[muskrat]

G'day Marqs. I can't see the 689/90 listed but a 389/90 is.
389/228    BSA 650cc 1966; A65 Lightning & Hornet    1 5/32"    25    3    270    0.11    3
689/228    BSA 650cc 1966; A65 Lightning & Hornet    1 5/32"    25    3    270    0.11    3
389/090    Greeves 250cc 1963; Motocross Special ME    1 1/8"    30    3    210    0.11    3
         Villiers 197cc 1962-63; 9E Super Sports (pair)    1 1/8"    30    3    210    0.11    3
Cheers

[BSA_54A10]

The above is how they left the factory 60 years ago so their might have been a few changes made since then.

[KiwiGF]

I'm no expert but doesn't the first 3 digits describe the carb model and the 3 numbers after the slash the jetting configuration?

So for example this means any 1 1/16" 376 monobloc carb can be re jetted to be right for an A10 that had a 376 as oem ....regardless if the 3 numbers after the slash are right for an A10 or not.

There are documents available which Amal numbers and which bikes they were fitted to, most carbs were fitted to several different models of bikes.

[muskrat]

http://porklips.org/~mason/moto/amal_specs.html
You are right KiwiGF.
Cheers