99101-124 jet in size #66 and #67?

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Got a bofeng carb, stock jet is a #70, changed it to a 99101-124 jet size #68, this seemed to help, but I still hear a faint four stroking WOT sometimes - id like to try a #67 and #66 jet to see if this helps.

Anyone know if 99101-124 comes in #67 / # 66? It seems they only run at #65 and #68. Would maybe a different carb model be compatiaible and have a #66/67 jet?
 

DAMIEN1307

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but I still hear a faint four stroking WOT sometimes
That should be considered normal and actually desirable since that faint little bit of four stoking will help keep the head cooler since it is washing more gas and oil over the piston and moving parts...I think your all set in that department now.
 

Chainlube

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Got a bofeng carb, stock jet is a #70, changed it to a 99101-124 jet size #68, this seemed to help, but I still hear a faint four stroking WOT sometimes - id like to try a #67 and #66 jet to see if this helps.

Anyone know if 99101-124 comes in #67 / # 66? It seems they only run at #65 and #68. Would maybe a different carb model be compatiaible and have a #66/67 jet?
Ride it for a couple days and do another plug chop and see what that says.
 

ImpulseRocket89

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Jets come in steps of 2.5, but keihin rounds it off. So from a 68 (67.5) next down is a 65. It isn't as big of a jump as you might think. I agree with the above suggestion. A plug chop will tell you everything you need to know. If you really believe a 65 is too small and the 68 is too big the only option at that point is to find a way to drill it to a bit between those two.
 
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