Tire size question

OK, so I’m looking to do Elgin in October with my Roam2 and I need better tires.

I’m running 700c x 40 right now with a heavy road bias. Looking for a gripper tire that can run lower pressure for comfort.
In my research, I’ve read that 700c converts to a 29er, but that didn’t make sense to me.
Using a straight conversion, 700 (assuming that is mm) should convert to 27.55, which would make it a 27.5-ish tire…

So what am I missing? The very widest tire in a 700 looks like a 45 wide.

Is there a conversion between 700c and the inch measure tires?
Thoughts/opinions on a grippy XC tire?



700c and 29" are the same size, both are 622mm bead seat diameter. As long as you have clearance on your frame you can put whatever you want. You’ll want to avoid putting very wide tires on very narrow rims, but in your case the frame will probably limit the width of tire you can use so it shouldn’t be an issue.

I am by no means an expert in XC tires (I use a mud tire for everything because it was cheap…) but I would try something like this to see if you have clearance for it. That’s if you expect hard pack, it’s not a mud tire. But it would probably be pretty decent for the amount of road (dirt & asphalt) at Elgin. mec.ca/product/5034-543/pana … 1109+51140

I read one guy thought 2.1" might be too wide for the chainstays on a Roam, so you might try a cyclocross style tire, something like mec.ca/product/5030-397/clem … 1109+51140

Agreed. I use a 29er tire on a 700c wheel on one of my bikes.

Thanks guys…it looks like my options just went way up!

Adam, those are the kind of tread pattern I was envisioning.