Big Bore jetting

I have a post started in the jetting section already, but thought I'd try here too....

I'm going with a Athena 480 big bore kit....

From my searches and such, it appears you jet leaner for the big bore.

kit is not delivered yet, so I do not know if the instructions get into jetting or not.

Anyone have any experience with this?

How much leaner in general, and is it leaner throughout, or just the main, or just the needle?

Thanks for any help!

I have a post started in the jetting section already, but thought I'd try here too....

I'm going with a Athena 480 big bore kit....

From my searches and such, it appears you jet leaner for the big bore.

kit is not delivered yet, so I do not know if the instructions get into jetting or not.

Anyone have any experience with this?

How much leaner in general, and is it leaner throughout, or just the main, or just the needle?

Thanks for any help!

When I bored my 426 to a 444 I used the same needle but went one smaller on the main and had to adjust the fuel screw. You only need to go a little leaner. The bike will probably run without changing your jetting, but you will fine tune it afterwards.

Thanks,....

I'm still researching...going to drop the main down one for sure....still debating on the needle/clip though....

I'm thinking I may have been just a tad rich to begin with, and I was going to drop the needle one clip if I left the bike alone. I'm also adding a SS Megabomb though.

I also have a email into Mr. JD, and I'm sure he will have some wisdom to share...:thumbsup:

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