Well, I got a big NO! from my indy when I told him I wanted to match up my back wheel to my fat 18" spoked front.
He says it'll throw off my ride, balance,geo, etc.
What do you guys think? Ever heard this before?
I never thought of it before, but there are more 21 front/18 rear, than 18 and 18...
So maybe ... I should keep my 18 with 16 back?

 

Should not matter. I know people with 18's all around with no issues. Stock Fat boys are 17's all around also.

 

Look for another indy. Many riders have that set up. Just throwing in my 2 cents...Expect some incoming replies on this one.

 

Even if it does, you'll adjust quickly.

 

I would think its overall tire diameter rather than rim size. I matched my front stock 16" tire diameter and width with my new 18" front tire.

 

Good point.
Are you running a 16 back in your sig pic? Looks good.

 

Yeah, stock 16", just because I haven't decided how I want to attack the *** end yet... The plan is to go 200mm.