Commuting - Wider Tires on Specialized Sirrus

I am wanting a bike for fitness riding, mostly on road, but want a more rugged and upright position like that offered with a mountain bike. I like the idea of bigger tires to absorb the bumps, curbs, potholes, etc. I was looking at mountain bikes,GF Tassajara in particular; However, most of the people here agree that shocks are a negative for mostly road and light trail riding. I don't care about the difference in speed.

I am wondering if a bike like the sirrus, with bigger tires might be the better choice. How wide of a tire will the Sirrus accommodate? Has anyone gone this route and have any comments?

Thanks,
Dave

Not only will wider tires make you slower, they will make it harder to propel yourself. I have 28s on my Giant Cypress SX and they are just fine. I'm sure you could go up to 32s but I wouldn't go up any wider. Too much work for fitness riding.

If you really want a mountain bike, you can buy the lower end ones with a rigid fork.

I just got my Sirrus last week. So far so good. I rode around some not so good streets and it wasnt to ruff of a ride.

I keep 28's on my sirrus. One of the benefits of the 28's is the ease I can propel myself. I'm sure the sirrus can accommodate something a little wider, but I am not sure it's worth the difference. Also, the sirrus should have a seat suspension that helps when you go over stretches of rough pavement. Mine came with the suspension as a stock item even though I got the base model bike. It is best to avoid the potholes altogether no matter the size of the tires.

The higher models forgo the suspension post for a "Zertz" carbon post with the goofy little insert.