BBK'd scoot bogs down when the throttle is wide open  By  rockvegas (Read 785 times)

First, try raising your needle. If it has an adjustable clip, move it down a notch (repeat if performance improves but is still not perfect). If the clip is not adjustable, you can find small washers that will fit around the needle and inside the needle housing, use one or two to raise the needle.

If you lower the clip as far as it can go and still have issues, you may need a larger main jet. I use a in my 50mm (83cc) bbk, and still had to lower the clip one spot below middle to prevent bog at WOT.

Once you get rid of the bog, check your spark plug porcelain inside the threads, you want a nice brown coffee color. White is too lean and dangerous (especially on a bbk). I went from to to main jets before finally getting that brown colored spark plug.

I checked the needle last night and it only has one groove in it with a washer and the clip in that one groove. I was able to move the washer from on top to below the clip, but that only netted me a half millimeter or so. Any other advice for raising it? Just find a tiny washer and slide the needle through it, even though it won't seat anywhere?

here is a gr8 video that should tell you everything you need to know. goto 6:20 if you only want info on the needle.

Try an open air filter if you haven't already or take the inside restrictor and front cap off the airbox.