I have a 2015 dyna street bob, with stock spoked wheels. A buddy has a set of wheels off of a 2005 softail, i am curious if these will fit? If so will i need a conversion kit? Pics below.

These are the wheels off of the 2005 softail.

 

'05 softail runs 16x3 front and rear. Street Bob ('06-'17) runs 19x2.5 front, 17x4.5 rear.
Those look like aftermarket wheels, do you know the sizes?

 

From what hes told me, they are both 18" wheels. That is all he knows about them, and i have not seen them in person to know any otherwise

 

If they're 18's I think the rear would be too narrow.
You can run 18x5.5 on the rear of your Street Bob, that's a max of 4 or 4.25 if it was on a softail.

 

I didn't see where OP specified what softail model the rims were coming from. Not all the softails are 16x3 front and rear. For example, a softail standard, night train, deuce, etc runs a 21" front wheel.

To OP, off the top of my head you're going to run into issues with regards to bearings and wheel spacers, sprocket alignment, and disc alignment. I think that year were 1" axle/bearings for the front and 3/4" for the rear, where your bike would be 25mm front and rear. I would pass on the offer.

 

OP~ If your bike has ABS, I'd pass on the offer too.