Tire considerations

[Specdog]

When you see oddball tire sizes such as 3.60, 4.10, 4.60, 5.10 this is NOT their inch size. A 3.60 actually correlates to 3.00 in standard inch category and 80 in metric category.. These oddball tire sizes are in a category of their own called Low Profile Inch. I know, it's confusing.
https://www.denniskirk.com/help_center/tire-sizes.jsp#lowprofile

 

[briansal]

Ahhh ok that makes sense.

 

[xschris]

Here is what the sohc xs400's came with.

 

[willem]

maybe you could get a bigger rim to go with the wider tire?

don't know what will fit in the stock forks, but I heard those are also replaceable