Need help picking scale for motorcycle

I have a few 8-9" figures I want to put on a motorcycle but i'm not sure what scale I should use. Any suggestions?

That is a really odd size figure. They're bigger then 1/12 scale figures (6") and 3 inches off the 1/6 scaled figures (12"). So just by dimension your figure is around 1/8 scale.

1/8th scales are a little more expensive than the other scales, and it mostly comes in model kits instead of already made diecast models.

Good luck!

Yeah i have the 2 final fantasy bikes that come with the Cloud Strife figure and he's 7". Playarts uses their own goofy scale like that for their kai line. I actually probably would end up modifying it anyhow I was just hoping to see what was out there.