My buddy has a 93 Heritage Softail and needs a new rear tire. Anyone know what size tire came on the back and what the biggest tire is that will fit? Thanks!

 

wow this wasn't a hard question, didn't think it'd make it to page 2 without a response....

 

You can go to Dunlop tires website and it will give you all that info or just call a dealer, they'll give you the right size and usually can tell you the largest also.
Metzler's website is the same way. Or an independent shop can tell you the same thing.

 

I have a 1999 Fatboy, very similar bike, and was looking into this same subject a while back. Generally there is a 130 on the back. Unfortunately, the biggest you can go is a 140. Not much improvement. However, if he really wants to spend the time and money he can go to a 150, but it means that he'll have to change out the sprocket and belt for one that is narrower. That requires a lot of work for only 20mm over stock. Not worth it.

 

Well according to Dunlops website it is a MT90B16. So if it calls for a 90 will it really fit a 140? Anyone else?

 

Yeah, it's either a 130 or MT90...same thing. It does not mean that it is actually 90mm wide. It's a name. Maybe someone else can answer why it's called MT90.

If you check out Dunlops website or whoever, the MT90 and 130 have the same dimensions.

 

It has an MU85B16 which I am having a hard time converting the size. I gather it's a 140mm wide but is the aspect ratio 85% what does 85 stand for? B means bias and 16 inch wheel.

 

It came with a 130. That also happens to be the highest stocker you can go with, without doing some work to squeeze in a 140. It really wouldn't be worth it. The rear tire on a Heritage is hidden by the FLH style rear fender anyway.