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Single Mk.1 Concentric carb

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anybody know best starting point for carb settings on single carb manifold for72 750 commando

thanks mike

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Pre....viously wrote:

anybody know best starting point for carb settings on single carb manifold for72 750 commando

thanks mike

Hi Mike The only settings I have are for a 850 single carb these are 32mm carb. main jet 270. needle jet .106. needle 2 ring. needle position middle. slide No 3. spray tube full circle. It is some thing to start with but I think it would be to rich for a 750 so try & come down from that. You should all ways start rich & work down in sizes. Good luck Peter

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I ran my 1965 Atlas for 10 years with a Commando head sporting a 930 Concentric on a single carb manifold.

The main jet was 240, needle jet .106 and slide size 3 cutaway. No air filter

It always started fairly easily, gave 65mpg and idled ok with a filter in the fuel line to trap any rubbish.

The plug colour suggested that the mixture was a little rich somewhere in the range butI choose not to fiddle with it in case I went too weak and caused a seizure.

The bonus of this set-up was never having to balance twin carbs every month which previously had to be done.

I have since moved on to a proper 750 Commando with an SU carb.

Starting is even easier, plus I can get up to 80mpg. My twinsAmals never bettered 50mpg at any speed.

Permalink

Previously wrote:

I ran my 1965 Atlas for 10 years with a Commando head sporting a 930 Concentric on a single carb manifold.

The main jet was 240, needle jet .106 and slide size 3 cutaway. No air filter

It always started fairly easily, gave 65mpg and idled ok with a filter in the fuel line to trap any rubbish.

The plug colour suggested that the mixture was a little rich somewhere in the range butI choose not to fiddle with it in case I went too weak and caused a seizure.

The bonus of this set-up was never having to balance twin carbs every month which previously had to be done.

I have since moved on to a proper 750 Commando with an SU carb.

Starting is even easier, plus I can get up to 80mpg. My twinsAmals never bettered 50mpg at any speed.

thanks i will start at this

mike

 



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