I have never had this issue personally, but I am guessing that the seal may be warped/ defected or something from the heat of the motor. I would say if you have to split the cases then replace all your seals with some good brand seals.
Check these out exactly what your looking for and price is fair.
http://www.ebay.com/itm/Yamaha-Banshee-Keihin-Carburators-Motion-Pro-Twist-Throttle-Cable-35mm-/200961505371?pt=Motors_ATV_Parts_Accessories&hash=item2eca3d385b&vxp=mtr
I have had two sets of OKO carbs and had nothing but trouble with them, I couldn't get them to flow fuel efficiently and also they were a pain to tune. It could be that I had a used set that someone probably destroyed prior to me buying them.
I need a few pieces to finish up, if you have them please PM me a price including shipping. Thanks
1. 2000 On/OFF Switch (square plug)
2. Swingarm Chain Slider
3. Rear Brake Block Off Plate
Need Tors removal complete kit with idle screws also need pod filters and outerwear for stock carbs. Let me know if you have these items.
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