Different width tires may require a different width rim. A 90/90 - 18 tire will have the correct profile on a 1.60 or 1.85 width rim. A 110/90-18 rear tire will have the correct profile on a 1.85 or 2.15 rim. That being said, you could run a 1.85 rim on both the front and rear and it would fit both rims. Here is the kicker, you don't know for sure what rim is optimal for each tire without checking with the manufacturer of the tire.Another rim question that I'm struggling to find the answer on...why are the front and rear two different sizes? I understand that the front and rear tires are often time different in size for handling...does the same apply to the rims?
Also, I've spent a good portion of today looking for some additional parts I'm going to need/want to replace. I'm starting with the exhaust as that will be needed for me to complete the installation of the Mikuni's...I'm looking at sourcing just headers so that I can do a non megaphone style exhaust. Can someone confirm these will work? I know it says CB360 on the web site but I'm surprised at the price. Not sure if I am missing something?
https://www.shironetw.com/index.php?main_page=product_info&products_id=798956
As always, thank you, and happy building!
Besides having the correct profile, the appropriately sized tire will also give the designed handling characteristics for the bike. In an earlier post, I noted that I had run a 110/80 - 18 front and a 130/65 - 18 rear on my CB350 race bike. Those were the Avon Am22 front and the AM23 rear and they are both speced to be used with a 2.15 width rim, because that is what some vintage race organizations limit some classes to. Both of those tires made the bike heavy handling and reluctant to initiate a turn. That is what I wanted, because I am a big guy, like to transfer weight to the front in a turn and have many years of racing experience and know what I need for handling, for me on a specific bike.
The pipes look like they would be what you need, but they are just the head pipes.