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 Post subject: MT250 needle height
PostPosted: Sun Jul 17, 2011 12:41 pm 
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Joined: Sun Jul 17, 2011 9:01 am
Posts: 14
Can anybody help me with the following; I have a 74 MT250 with a 004A carburettor. The needle has five positions for setting the needle height with a circlip at the top of the needle. What is the factory setting for the height of the needle? Any advice with respect to adjustment of the height? What engine running symptoms should cause an adjustment?


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 Post subject: Re: MT250 needle height
PostPosted: Tue Jul 19, 2011 10:31 am 
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Joined: Sat Dec 04, 2010 6:24 pm
Posts: 81
In theory the middle position would be ideal. Drop the needle to lean it out some & raise the needle to richen it up.

I don't know what the OEM setting is supposed to be. Where is the needle set at now & how well does the engine perform?

Good luck
~JM~

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 Post subject: Re: MT250 needle height
PostPosted: Tue Jul 19, 2011 11:50 pm 
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Joined: Sun Jul 17, 2011 9:01 am
Posts: 14
Thanks. Needle is now at its lowest position, so I will raise it to middle. Engine runs well top end (above 4000 rpm) but throttle response is a little hesitating low end. This and some pinging noice, I guess, could result from lean mixture low end, so heightenig the needle seems to make good sense. Will post how it works out.

RB


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 Post subject: Re: MT250 needle height
PostPosted: Mon Aug 08, 2011 11:06 am 
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Joined: Sun Jul 17, 2011 9:01 am
Posts: 14
Been testing, adjusting, testing, adjusting, testing, ... Engine now runs great. Had to keep the needle in the lowest position - due to the jetting of the carb. Got some tips and searched the internet.
:D :D :D


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