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Oct 25, 2007
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I've a newly-rebuilt Commando 920 Mk2A fitted with Tri-Spark Ignition (a superb bit of kit!) and single Amal 36mm Mk2 Concentric. The bike runs beautifully and starts reasonably well from cold (3 or 4 kicks) - it's hard kicking though!!. I noticed though when the engine is hot and I stop it when I come to restart (even after only a minute) I need to apply the choke lever (as if starting from cold) - it starts OK then but something can't be right - any ideas please ? :?
 
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Oct 12, 2007
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Mark,

Have you carefully checked the float level? I've not had any experience on Amal MKII's, so I'll defer to someone else on those. I'm only thinking of basic carburetor principals. Keeping in mind that you are running a bigger engine and a relatively small single carb, I'd try running a higher float level.

That 920cc must really get the job done from zero to 100mph. What's the top end?
 
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Hi Jim - yes the motor does pull hard (I've upgraded the clutch and gearbox) - I haven't tried the 'top-end' yet as it's still running-in.
 
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Mark two's take some getting use to. They seem to need the enricher's but like them turned off as soon as possible as well. On re-starts I have found a trick that helps me you might try. On with the enricher but don't kick just push it through slow now enricher off give it just a tiny amount of throttle and a swift push though. If it falters repeat and it should catch on. After a while your ear will tell you when it needs the enricher's on for a while. If you are running a coil that can take the heat plug gaps up to .040 seem to help burning lean mixtures.
 
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Thanks Norbsa - I tried your idea for starting when the engine's hot - it works !!!! :D
 
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