Partition by sale by spouse in California

Sam is correct about partition. You also have another choice, an action for an accounting. Tenants-in-common have a right to their percentage shares of the income from a property rented to others. The owner collecting the rents can deduct reasonable expenses, but must account for the revenues collected and spent and pay you your share. This remedy is also available if you own the property as a corporation, limited partnership or limited liability company, but the right to distributions might be more complicated. An advantage of an accounting is that it does not result in selling the property or one of you buying out the other. The disadvantage is that you still both own the property together. Dana Sack  

Yes, any co-owner of property can sue for partition.  The percentage of ownership is irrelevant.  There is little to no defense to a partition action and the more you fight, the less money everyone has.  You can buy out the co-owner's share or sell it and get your portion of the proceeds.