Carby longer needle opposed to a shorter one

each type is matched to the needle jet in operates in - it looks like a plain brass tube, but contains the pinch point that is controlled by the taper of the needle

swapping the needle or needle jet between carbs usually results in a non-functioning carb
 
What if the taper is the same but the needle is longer? Would that be a higher rev or a will it flood or what will happen??
 
longer needle means leaner part throttle and more throttle travel before you get to full throttle jetting
 
stock bikes are jetted too rich (NT carb) so a longer needle might work well at leaning it out.
 
I've never seen good results of mixing carb parts, but one might get lucky and hit on an improvement.
 
I've switched to a longer needle to lean it out for the mid range. I was at the last clip slot on the shorter needle and this gave me another notch to the leaner.
 
="Tim Bailey, post: 422686, member: 26417"]I've switched to a longer needle to lean it out for the mid range. I was at the last clip slot on the shorter needle and this gave me another notch to the leaner.
How'd that work out? The only thing I've noticed about the needles is some have 4 notches others have 5 , must compare them more closely see how much they vary . Did your longer needle have 5 notches and short one 4?
 
I think the same amount of notches, one is about an 1/8" longer. Like Jag said, these engines are rich from the factory. By dropping the needle I was able to get a smoother engine at mid speeds. But frankly, I just bought a "Dollorto Type" carb on ebay. Although I've not dialed it in completely the top end is much better than I was able to get out of the NT Speed Carb. Mid range is smoother as well.
 
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