Sorry about another tire thread but I really need this question answered!

[Subtle Focus]

Well very happy with the progress I made on my 1979 xs400 today, I started my bike up for the first time since I bought it back in August of 2011! The only thing there is left to do is buy some tires, so here is my question if you fellows and ladies of course would be so kind to answer.

Question: The front rim is 18x1.85 and the rear rim is 16x2.50, the rear rim says suitable for tubeless tire but the front does not. It currently has a tube tire on the front and is off a xs650 I presume. Is it safe to run a tubeless tire with a tube on the front?

The main part to this question is what size tires can I safely run on my bike with those size rims? It currently has on the front 3.00x18 tube tire and the rear is has a tubeless 120/90-16. The only sizes I have been able to find for a good price are:
Front: 100/90-18
Rear: 130/90-16

I assume there would be no issues running the larger front tire on the front since the corresponding size for 3.00x18 is 90/90-18 but I am just concerned about going up a size on the rear. Does anyone have a 79' xs400 with a drum brake tire on the rear that would know if there would be any clearance issues. I am flexible on removing chain guard if it will allow me to run this tire if it interferes.


Any info would be much appreciated.

-Subtlefocus

 

[ThePsuedoMonkey]

putting a tube into a tubeless is fine. You will probably have to play with the rear end to make it fit though.

 

[Subtle Focus]

By play what do you mean...? lol

 

[Onetype]

Alot of people are running a 130 on the rear. Nothing new here, you'll be fine.

 

[OliverB]

Perhaps you have a rear wheel from an "80 or '81. Those were so marked. My son had a 130x90 on the rear of his '81 XS400 and it fit w/o rubbing. Some have reported clearance problems on bikes older than 1980. You won't know until you try it. I run a 120x90 on the rear of my '80, which is the size Yamaha recommended for the '80 & '81 rear tire. On the front with my tubeless rim, I run a 100x90 which is a size larger than the original 90x90. I like the look of the slightly larger tire.