Amal float level

I know the subject appears all over the forums, but can anyone tell me the definitive level for float height on MKI concentrics? I see info that says 40-60 thou inside the bowl, yet the Norton tech info says 3/32" outside the bowl. Which is right, and how much difference does it really make?

Thanks

It's the latter, because on the commando motor the carbs are mounted at an angle. Yes, it will make a difference in your mixture. Lower is leaner, higher is richer as it takes more or less vaccuum respectively to draw the fuel into the carb.

I believe you will find that there are different opinions on this subject.
I prefer to keep the float level below (inside). On my bike a float level above the edge gave a too rich mixture and I found that 1,5-2,0 mm below works the best for me.

Regards,
Per

maylar said:

I know the subject appears all over the forums, but can anyone tell me the definitive level for float height on MKI concentrics? I see info that says 40-60 thou inside the bowl, yet the Norton tech info says 3/32" outside the bowl. Which is right, and how much difference does it really make?

Click to expand...

Note that "float height" and "fuel level" are not necessarily the same.

Well, I guess I'll just have to experiment then. I have mine set at .050" below the top (inside) and I'm definitely running lean. I've checked and rechecked everything else.. pilot jets, intake leaks etc.. It's hard starting, wants the choke for a long time, and the pipes are turning purple. The carbs have about 5000 miles on them, so I don't think the slides are worn yet. They ran well when first installed but I've twiddled them a lot since then.

A clarification, I'm talking about float height and I measure it by holding the bowl upside-down.

0,05 should not give a lean mixture I think. Combined with 1 1/4 turn open air screws and 3,5 cut should work reasonably fine on a standard 850. If not I would suspect partly clogged idle circuits (seems to be the most common problem with Amal).
If the pipes are getting discoloured you might have your ignition set a bit late?
I like to check the temperature at the end of the silencers to confirm they are at the same temperature.

By the way, you are in CT, anywhere near Hartford? I do trips to the states, normally to Hartford since I work for a Hartford based company.

Regards,
Per