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The "finished" project that became an engine swap...

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Hi 

This might seem a daft question, but I've not really done much work in the past on carbed bikes, all my others are fuel injected. 

I've just taken delivery of a new engine to put in my 2001 S - the engine is a 2007 S with an Athena big bore kit taking it to 440cc. 

My question is, before I fit it and make getting to the carb difficult, what do I need to do to the carb to prepare it to work well with the increased capacity? I'm on a stock Mikuni carb, standard jetting, although all brand new needles/jets etc from when I refurbed it. 

Don't want to buy a new carb, but I am happy to get new needles or whatever as required. 

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I raised the needle one notch when I put my big bore on. Someone else will have to chime in on the main jet. I can't remember what I did (can't check because I have a different carb now). I thought I remember someone saying use a SMALLER main jet because of the increased vacuum or something?? Idk doesnt sound like it makes sense but I'm pretty sure that's what I did. Either way it ran beautifully. Also for reference, I had the JD jet kit before installing the big bore so I used what was in the kit. I suggest buying that and also doing the 3x3 if not already done. 

Edited by Bm1997

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New engine is in. I’ve done a 3x3 on the air box as well, and I’ve deleted the 2nd air cleaner (had a hole in the pipe anyway)

I’m currently struggling to get it to idle properly, although I am trying to sort air flow issues before I look at fuel.

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After air is sorted and presuming I can get the bike to idle just with the screw, I will probably get a JD kit to mess about with main jets etc

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