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O-ring Mod Question

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I just recently purchased a 2008 KTM250sxf and was noticing the bog down low right off idle.  I've seen pictures of people using safety wire instead of the o-ring, and after trying the o-ring first I noticed that when you use safety wire it makes the shot much stronger and shorter.  There is no flex in the safety wire which gives it a much more instantaneous reaction to the throttle drum being turned.   Would there be any dis-advantage to this?  I don't want to mess anything up, but like I said I have seen pictures on the forum of people not using the O-ring.  I started it up last night and everything seems just fine and I can straight up whack the thottle open and the bike springs to life with no hesitation at all.  This is my first experiences with an FCR after coming from a CV carb off of an XR250R. 

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The preferred method is to use an upgraded apump linkage spring

Tokyo mods, Merge racing, R&D

It gives the the linearity of pump actuation that follows the throttle action, without the risk of linkage binding, which the safety wire eventually seems to do as it falls apart.

The o-ring is better than nothing, but it is not linear, and stretches with heat, and fails pretty fast

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