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Hi all! New to Honda Twins and I'm coming in with questions regarding tuning my VM30 Mikuni carbs.

Over the last couple months with my CL350 I've taken apart the engine to re seal it and found that there was a bunch of pitting in one of the cylinders, so I went ahead and got the cylinders bored out to 1.5mm over stock and got 1.5mm oversized pistons for it and put it all back together (not to mention with much struggle with other things breaking in the process, of course)

But at any rate, I had gotten brand new Mikuni carbs for the bike before the engine started leaking a bunch of oil, and when the bike was on time, they kicked over first kick on a cold start. Now, of course, they wouldn't be tuned properly given the changes that have been made to the bike. So I guess my question is which jets should I be looking at to replace with different sized ones, etc. And is there anything else I need to worry about (aside from air/fuel adjustments) in tuning these? Or really just any insight or any experience with something similar?

Was considering taking the bike to someone to have them tune them for me but I live in Western WA and there are few and far between who work on old bikes and are willing to take a look, as well as the Mikunis seem relatively easier to work with than stock carbs.

Thanks!
 

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going from the stock 64mm bore to a 65.5mm bore wouldn't require much if any jetting change. If your VM30s were 100% perfectly dialed in for the stock bore (which I highly doubt) they would still be 95% to 98% dialed in for the overbore. most people who install mikuni's on their 350s rarely achieve better than 60% to 75% accuracy in their fueling. most are over rich wich would mean your slight overbore would actually improve things ever so slightly.

only way to know for sure is to follow the instructions for jetting in the sticky

running it on a Dyno with EGA makes it much easier.
 
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