I've seen these before... most of them are fakes and some do not even have replacable main jets. From what I see in that second pic, that 'Keihin' carb doesn't use genuine Keihin jets. Suspicious.
Supposedly these big carbs are designed for 50cc scooters with a 70cc big-bore kit, but I have my doubts about how well they work with an engine that small. Stock carb on those 50cc scooters is 19mm. I know because I've been pulling my hair out trying to find a replacement one without that garbage electric choke. Then again, YZ 85's are fitted with a 28PWK from the factory, so you never know.
Either way, I'd rather get a good used, real 28pwk off a YZ85 from Ebay for $ 70.00 or so than take my chances with this one.
