Author Topic: Monobloc to concentric  (Read 924 times)

Offline TT John

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Monobloc to concentric
« on: 01.06. 2013 19:09 »
 *????*Hi All. I have recently converted my A10 plunger golden flash from monobloc to concentric, it seems to run o.k. but sometimes when it's  ticking over it will just give a spit back, then stop, now, the question is do I need to change the jetting? I have heard some say that it should be reduced, if so what size main jet should I fit to try this out? also should have to drop or raise the needle?
Many thanks in advance.

TTJohn

Offline Triton Thrasher

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Re: Monobloc to concentric
« Reply #1 on: 02.06. 2013 16:17 »
Google "bushman amal" or similar.

Why did you change carburettors?

Offline A10 JWO

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Re: Monobloc to concentric
« Reply #2 on: 02.06. 2013 17:57 »
I have a concentric with a 170 main and I currently have the needle on the weakest setting. Starts fine, just needs warming up to settle everything. Mine is running in so we will see. Took several goes to clean out the very small drillings ( Amal 626 ). See  my thread "Which Jet " Lots of good input from the gents on this forum.

Regards Colin.

Offline fido

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Re: Monobloc to concentric
« Reply #3 on: 02.06. 2013 20:48 »
I regard the monobloc as a superior carb to the concentric, which is a bit flimsy and distorts if you tighten it fully to the manifold.

Offline TT John

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Re: Monobloc to concentric
« Reply #4 on: 03.06. 2013 08:10 »
TT. I changed to a concentric from a monobloc because it gave me more room between the top of the carb and frame, my plunger has a S/A head which had a longer inlet manifold and angled, so I cut that down parallel taking off about 1/8" which gave me the extra space I needed.
The reason I used that s/a head was that at the time I could not get the correct one at the time and I still haven't got one.
Colin: Thanks for your input I might give that a go, I'm not sure what jet I have in there at the moment but I will check your thread.
Many thanks to all for the replies.