Originally Posted by Van Buren

For the front you'll need new axle spacers and possibly a rotor spacer. I went from a 16x3 front to a Street Bob 19" front and while the dealer told me all i had to do was fabricate new axle spacers i actually had to fabricate a rotor spacer as well. While both a re mid-glides, the 48 hub is offset where the rotor side is larger than the right side of the hub. On a Street Bob the hub is symetrical. Something to look out for.

Originally Posted by hank-hill

So I decided to try something a little different on the rear and took a chance with a Fatbob tire and guess what after a little fiddling the darn thing fit.


This is the rim & tire I bought its from a newer Fatbob not sure what year.

Originally Posted by hank-hill

Here are a few more with the 180/70/16 on the bike


Can't get much closer than this



Side view the bike is on a jack but I am running 13" shocks

Here is shot of the back with my new to me 180/70 16 back tire. Fits like a glove, I mean real close but it works.





I can't seam to get a great angle but the belt is close and does not rub

Originally Posted by hank-hill

I used all the stock spacers, disk, pulley everything.
There is a special order on how to install it since it is about as wide as you can go on a stock sporty. Also I replaced my fender with a full fender so it's a tad wider due to the fact that it's all metal. If you look at the 48 fender from under neath and the sides you will see its plastic on the sides. This May or may not be a slight issue if you run low shocks, I have 13". There is a simply solution and that's just get a rim and run a 170/70 16 which is a common import cruiser size tire. The stock Dunlap 427 on the Fat Bob is really a large almost dual sport type tread so another 180/60 16 may be another choice. I did test fit the fender over the tire with everything off the bike and it it fit over just fine. I should have done this with the stock 48 fender and will next time I take it off.
So what is different about the install well glad you asked. Since the tire is so wide you can't just roll it in there with the pulley and brake disk on. Normally you can just roll past the brake caliper but the wider tire hits even if you try to angle a bit. So if follow the order below it will fit just takes a few minutes more. And it really is just a few more steps
1. Remove all 5 disk bolts
2. Remove axle
3. Lift bike enough to get the spacers out and disk.
4. Remove the caliper. Now be very careful !!! Mine was on on so tight with so much red loctite that the threads came out with it. I have purchased a 12x1.25 to correct this but still annoying it happened anyway.
5. Remove the caliper bracket. I found it best to side it back towards the rim then angle it down so it comes out the bottom. There is nothing else holding it on but a light rubber mallet did help free it up.
6. Slide belt off rear pulley and remove wheel.

This is a standard Fat Bob rim that I believe was used until this year when they went with a black rim. I will have it powder coated and that will run around $100, so for me it will be $300 total. Not bad for a 180 rear.

The other option could be to remove the pulley, install wheel, than put it back on. My pulley threads are fine but seamed like they were tighter going in so I felt it better to go the route listed above.

I'm now fat and happy

Originally Posted by hank-hill

One other thing that did throw me for a loop at first is the tire direction arrow. I thought at first it would not work because the pulley bolt holes were to small. I then remembered that the twincam trans is on the other side. I know this should have been common knowledge but I didn't think about it at first and thought i was not gonna work. Now I will need to switch the tire around but I will do that when its coated.


The arrow shows the tire is on backwards, so you just need to switch it around

Originally Posted by sroc3

Oooo this should be sweet!

Originally Posted by grbrown

A snag of sorts is that AFAIK the big twins use larger pulley bolts than the Sportsters. Also don't use a narrow belt in a wide pulley - that thing is going to walk around across the pulleys! A narrow rear pulley will centre the belt on the front pulley, as long as they are properly in line with each other (which is how the big twins all work).