Amal finishing

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From cleaning a few concentric 's over the years there is no single answer as I am sure the casting alloy has varied over the years as their reaction to chemical cleaners differs. There is also a aluminium body knocking about which the pre 65 trials guys use on the 600 series.
 
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Aren't Amals made out of hummingbird egg shells? They warp and deform if you look at them too long.

I doubt the set of early 930 Amals I have had much shine on them new out of the box. I think I used lacquer thinner and a Q tip or old tooth brush to remove the yellow/brown build up around the tickler and float bowl joint. Really have to keep after it though. Never occurred to me to polish them.

The Amals I have have never had white fluffy build up on them, but I keep the bike covered. When I neglected it entirely for decades all kinds of fuzzy white crap built up on various smooth alloy engine and hub surfaces. That stuff is easy to hand rub out on a smooth surface though.

Edit: Mine are packed away in a box, and look about as good as they ever did. I checked a week or so ago to see if I had the slides sleeved. I did. Records say I gave them to Radford to be sleeved. Still didn't keep me from packing them up.
 
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i'm wondering if you could seal a fresh, clean, carb body with a clear dichromate coating? according to the following, adds a corrosion protective coating, brightens up the surface and gives a blue tint. i know they seal and color auto carbs with yellow dichromate - gives carbs a light olive color with rainbow effects. back in the day, colored many carb body castings with yellow dichromate.

Joe, Thanks for the link. FYI, dichromate coating is a generic term for what is more commonly known as Alodine or Iridite. They are the two biggest players [products] in this field. This does add excellent corrosion protection, but is not a "plating". I know you were careful not to call it that, but Gatto implies it. It simply converts the surface metal, approximately .0002" to .0003" deep. It does not improve wear of the metal, and will quickly wear off on rubbing surfaces [throttle valve O.D. and main body bore] Because of this, it would wear off if you try to polish up the exterior of the carburetor.
 

cliffa

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What gives the best appearance result when restoring old Amals?

Light machine polishing?
Fine sand blast, low pressure?
Vapor blast?

Photos of restored Amals welcome here.
"What gives the best appearance result when restoring old Amals"

Surrounding them in a cylindrical steel tube ( a dustbin ). :D
 
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Joe, Thanks for the link. FYI, dichromate coating is a generic term for what is more commonly known as Alodine or Iridite. They are the two biggest players [products] in this field. This does add excellent corrosion protection, but is not a "plating". I know you were careful not to call it that, but Gatto implies it. It simply converts the surface metal, approximately .0002" to .0003" deep. It does not improve wear of the metal, and will quickly wear off on rubbing surfaces [throttle valve O.D. and main body bore] Because of this, it would wear off if you try to polish up the exterior of the carburetor.
i could be wrong and may not have all the facts, but i thought Alodine or Iridite was a conversion coating for aluminum. dichromate's primary use is to seal cad plating. that's where you get the yellow-gold nuts and bolts. it also reacts with zinc. in fact, fairly sure the only two metals it reacts with is cadmium and zinc. the yellow di is what gives automotive carbs that oilve-rainbowish color. provides minimal protection. it's mostly cosmetic.
 
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i could be wrong and may not have all the facts, but i thought Alodine or Iridite was a conversion coating for aluminum. dichromate's primary use is to seal cad plating. that's where you get the yellow-gold nuts and bolts. it also reacts with zinc. in fact, fairly sure the only two metals it reacts with is cadmium and zinc. the yellow di is what gives automotive carbs that oilve-rainbowish color. provides minimal protection. it's mostly cosmetic.
Alodine 1201 & Iridite 14-2 are used primarily on aluminum alloys. They both have a gold dye added. There are other variants of both products for other metals and there are also variants without the gold dye added [clear]. The active ingredient in all these products is hexivalent chromic acid. The dye is added simply to make it easier to tell when the metal has been soaked in the solution for the proper time period. These products are available in both liquid [$$$] and powdered form. In powder form, they resemble the old "freeze dried" powdered instant coffee. [large brown crystals]

https://en.wikipedia.org/wiki/Chromate_conversion_coating
 

Tornado

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Would not recommend using Gallium on your carbs if they have Alu in the metal:

 

elefantrider

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Going to try soda blast or vapor blasting.
Just looking for a return to factory finish.
Need to get rid of stains and white corrosion.
 
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elefantrider

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I need to buy a new float bowl because the banjo bolts threads have fused to the bowl threads, destroying them.

Thinking of changing for the older drain plug bowls. Of those here who have them, do you actually use the drains?
Or is it just another fastener to vibrate loose?
 
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I used the drains when tuning for a 2 into 1 exhaust. Easiest way to get at the main jet is through that hole in the bottom. Also I would drain the bowls before taking them off for whatever reason. The drain plugs made it less of a mess to deal with. Those plugs never came off due to vibration which is substantial on a solid mount P11. The plugs in my 930's are long hex metal plugs. The plastic plugs that came in the bowls were a real PITA to work with and basically junk as far as I'm concerned.
 
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The plastic plugs that came in the bowls were a real PITA to work with and basically junk as far as I'm concerned.
Amal sell plated brass ones too, not sure why they use the plastic ones at all.


amal_image-2910_original.jpg
 
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I should clean mine up too, but they are not being used, so motivation is a little low.

This is a dirty Amal 930 I bough in the 1970's. The finish isn't anything like any of the cleaned versions shown. Sort of a satin grey alloy look. I'm relatively certain this is the finish as they shipped in the 70's, but without the grime around the tickler, at the bowl joint, and fuel inlet. I like the look of the cleaned carburetors. Mine are really pedestrian looking.

IMG_6069ss.jpg


I used the deep drain plugs because I thought they would help with keeping fuel around the mains on extended WOT sections of rural road. Probably made no real difference other than the placebo effect.
 

Tornado

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I should clean mine up too, but they are not being used, so motivation is a little low.

This is a dirty Amal 930 I bough in the 1970's. The finish isn't anything like any of the cleaned versions shown. Sort of a satin grey alloy look. I'm relatively certain this is the finish as they shipped in the 70's, but without the grime around the tickler, at the bowl joint, and fuel inlet. I like the look of the cleaned carburetors. Mine are really pedestrian looking.

IMG_6069ss.jpg


I used the deep drain plugs because I thought they would help with keeping fuel around the mains on extended WOT sections of rural road. Probably made no real difference other than the placebo effect.
I like thos big extended air and idle adjustment screws. Are they the brass ones í've seen on e bay? Ive fitted the plated steel extended ones but they do not have the big knurled heads like your. I can tweak them with gloves on from riding position so not too bad. Really got fed up with stocks requiring a small blade driver to make a wee adjustment.
 
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I like thos big extended air and idle adjustment screws. Are they the brass ones í've seen on e bay? Ive fitted the plated steel extended ones but they do not have the big knurled heads like your. I can tweak them with gloves on from riding position so not too bad. Really got fed up with stocks requiring a small blade driver to make a wee adjustment.

I got them from Raber's Parts Mart in the late 80's. Hard to tell what they are made of. I'd be guessing. Definitely not brass though.
 
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Amal made knurled screw for the Mono block and pre Monoblock carbs, there are some like it on the internet.
 

Tornado

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CBS seems to list a few types now:


Here's an example of the brass ones...bit pricey at $29 a pair:

thumb-screws_1024x1024.jpg


Mine are similar to these but without knurling and a mirror finish:

622-169-EXTENDED_1024x1024.jpg
 
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