Float Level

The level of the fuel in the bowls must match and be correct this setting effects all the other adjustments and must be done as a matter of course as a base line fist before you play at anything else.

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I believe the factory float setting is 2mm or .080 inches below the lip of the bowl.

It is also my understanding that the float should be set higher for a Commando, due to the angle of the carb. How much higher is the question.

Can anyone recommend a float level setting for an 850 Commando MKIII,
to start as a baseline?

I set my 850 MkIII's (and my T140V Bonneville's) carb floats to 1mm/.040" below.

http://www.jba.bc.ca/Bushmans%20Carb%20 ... tml#5FLOAT

The correct answer is adjust till your air screw is best at 1 1/2 turns for your gas supply.Given that you have used a drill .016 on the air jets. Today's gas acts rich so maybe the manufacturers service note that says 2 mm is not bad? Your mileage may vary.

norbsa48503 said:

The correct answer is adjust till your air screw is best at 1 1/2 turns for your gas supply..

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I put a NEW pair of Amals on my Mk3 and set it initially at 1 1/2 out, which it does recommend in all the amal notes and tuning items, however I got bad spitting back form both carbs, I adjusted the air screws until the idle was smooth , I ended up with one out just over 1/4 and the other 3/4, with a good tan colour I queeried this with Surrey's tech. dept, they reckoned it was ok as long as it was running fine and it didn't really matter as 1 1/2 was a starting point. However something nags me in the back of my mind that something may not be quite right, hopefully I'm wrong. When I get back to the bike I'm going to check them through again, float heights, air leaks etc.
Cheers
Robert

My experience with new Amals is similar. Float level was way out of whack (one was about 3 mm above the float bowl). After proper adjustment, screws were 1/2 and 1/4 out...

Planning on installing chromed slides, will fiddle with needle settings etc. to get a better adjustment range then...

Cheers,

- HJ