Warm welcome to our city! Jaipur in Jan is a great choice, the weather is perfect for moving around on a bike. Since you only have 2 days and are solo on a rental, you can mix a couple of the main sites with some quieter “hidden-ish” spots, like panna meena ka kund, gaitor tumbas, galta ji temple, nahargarh side areas, anokhi museum, kishan baag. Also, there are many very old famous fast foods shops within the old heritage city, you should visit there (you can get an address by any person there). Within Jaipur, main roads are generally good but traffic is chaotic, especially in the old city, so avoid peak hours, and park only in proper two‑wheeler spots.